JPH09295573A - Traveling mechanism in pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the traveling performance in a stepped part and a bent part by constructing a pipe traveling mechanism adopting the concept of the so-called CCV in which traveling is performed while individually controlling four traveling driving wheels disposed radially in such a manner as to intersect perpendicularly to each other in the periphery of the device main body according to the sensor output corresponding to the attitude of the device main body. SOLUTION: When a traveling device is inserted in a piping 12, four traveling driving wheels 5 disposed radially in such a manner as to intersect perpendicularly to each other on the outer periphery of the device main body 1 are energized by springs through each wheel support arm 3a to be pressed to the inner wall of the piping 12, so that the device main body 1 is supported at four points on the plane. Simultaneously, an angle measuring roller 11 is energized by a spring through an arm 10 to be pressed to the inner wall of the piping 12. In such a condition, at the time of turning the travelling wheels 5 through a worm 7, and a worm wheel 6 by a motor 8 to travel, the attitude of the device main body 1 is detected by each potentiometer 9, and the drive of the motor 8 is controlled in such a manner that the angles of paired wheel support arms 3a to the arm 10 are equal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe traveling mechanism used for maintenance and inspection of pipes.

[0002]

2. Description of the Related Art In a city gas supply system, for example, many of the gas pipes called main pipes have a diameter of 100 mm to 200 mm, and the extension distance is 10,000 km or more. For that purpose, a mechanism for moving the sensor into the pipe is indispensable. In addition, these gas pipes are often buried under the main roads, so it is necessary to reduce the number of excavations to reduce the impact on traffic and reduce costs. It is desired to develop a mechanism that can move the sensor.

Mechanisms for moving the sensor into the pipe are roughly classified into a push-in type, a pressure feed type, and a self-propelled type. The self-propelled type has a driving force, so that the push-in type is used. It has superior performance as compared with the expression type and the pressure feeding type. The self-propelled type includes a crawler type, a wheel type, a peristaltic movement type, and a walking type, and the wheel type is advantageous from the viewpoint of miniaturization and high moving speed. The present invention relates to this wheel type traveling mechanism.

By the way, in the wheel type traveling mechanism, in order to obtain a propulsive force, the wheels are brought into pressure contact with the inner wall of the pipe and travel by frictional force. The pair of wheels that come into contact with the pipe wall become the inner and outer wheels, and the path lengths of them differ.Therefore, if a mechanism to absorb this difference in path length is not attached, the wheels will pass through the curved pipe section without slipping. You cannot do it. For this reason, if the frictional force between the wheel and the pipe wall is set to a large value in order to obtain a large traction force, it will be a great obstacle when passing through the curved pipe section, and in order to secure both a large traction force and the passability of the curved pipe section. Requires, for example, a configuration in which traveling drive wheels for traveling are slid sideways, and a path length absorbing mechanism such as steering and a differential gear is required.

[0005]

However, such a path length absorbing mechanism has the following problems. a. In the case of a mechanism that uses wheels that slide sideways, it is absorbed by a passive posture change, so it depends on various factors such as the direction and angle of the pipe, and the weight of the pipe itself when pulling, The traveling device main body often shifts from the center of the pipe, and the traveling device main body may come into contact with the pipe wall and may not be able to move smoothly. b. In the case of a mechanism using a steering wheel, the structure becomes complicated, automatic control is difficult, and human remote control is required. c. The differential is a desk-level mechanism because it has a large structure and a heavy weight, and has not been realized yet.

The present invention was devised in view of the above points, that is, CCV (Contro), which is a concept originally developed in the field of aircraft, which is typified by fighter planes and the like, which emphasizes mobility.
This is a configuration of the in-pipe traveling mechanism that reasonably incorporates the concept of lConfigured Vehicle).

[0007]

In order to solve the above-mentioned problems, according to the present invention, two pairs of wheel support arms are arranged in an orthogonal radial pattern on the outer periphery of the traveling device main body, and one end side of each wheel support arm is arranged. The wheel support arms are rotatably fixed to the traveling device main body, and the pair of opposing wheel support arms are configured to be movable inward and outward by interlocking with an interlocking mechanism, and are biased outward by springs so that each wheel support arm is attached to each wheel support arm. Is equipped with a traveling drive wheel and its drive mechanism on the other end side, and an angle measurement mechanism in which an angle measurement arm is rotatably projected is provided.The angle measurement arm has an angle measurement roller on the tip side. We propose a pipe running mechanism that is installed and urged outward.

Further, according to the present invention, in the above structure, the interlocking mechanism is configured such that the traveling device main body is provided with the rail portion so that the slider can be moved in the propulsion direction, and the pair of opposed wheel supporting arms and the slider are respectively arranged. We propose to connect links between them.

Further, in the above structure, it is proposed that the rails have a common structure so that the sliders corresponding to each pair can be moved to one end side and the other end side.

Further, in the present invention, it is proposed that the traveling device main body has a tubular shape in the above-mentioned configuration.

According to the above structure, by providing the pair of wheel support arms arranged in the orthogonal radial pattern on the other end side,
The four traveling drive wheels arranged on the outer periphery of the traveling device body on a plane are urged outward by springs and are pressed against the inner wall of the inserted pipe. Therefore, in this state, the main body of the apparatus can be moved into the pipe by driving the traveling drive wheels.

In the above-described state, the angle measuring roller at the tip of the angle measuring arm is constantly pressed against the inner wall of the pipe by the biasing force of the spring, and the angle measuring mechanism includes the angle measuring arm and the wheel supporting arm. Produces an output according to the angle formed by the vehicle, and this angle corresponds to the angle formed by the traveling device body and the pipe.

Therefore, if the traveling drive wheels are driven so that the angles measured by the respective angle measuring mechanisms of the pair of opposing wheel support arms are the same, the traveling device main body will have a straight pipe portion and a curved portion. In any of the pipe parts, the pipe is always oriented in the axial direction of the pipe and can travel in the pipe in this state.
The difference in path length between the inner and outer traveling drive wheels in the curved pipe portion is absorbed by the difference in the drive distance between the respective traveling drive wheels, and slip does not occur.

In some cases, if the respective traveling drive wheels are driven so that the angles measured by the respective angle measuring mechanisms of the pair of opposing wheel support arms are at a constant ratio, the traveling device main body is Can be tilted at a predetermined angle from the axial direction of the pipe, and therefore the traveling device body that was traveling in such an inclined state or traveling in the axial direction of the pipe can be inclined at a desired position. You can

The traveling apparatus main body can be formed in a tubular shape, and in this configuration, wirings can be passed through the traveling apparatus main body.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 generally shows the basic configuration of an example of a traveling device (robot) to which the traveling mechanism of the present invention is applied, and FIGS. 2 to 5 show a part of the basic configuration of FIG. . In these drawings, reference numeral 1 denotes a traveling device main body, and in this example, the traveling device main body 1 is configured as a rod-shaped body, and a slider 2 is supported on the outer side of the traveling device main body 1 so as to be movable in the axial direction. The slider 2 constitutes a pair 2a, 2b corresponding to two pairs of wheel support arms. That is, the rod-shaped body that constitutes the traveling device body 1 includes the sliders 2a and 2b.
Constitutes a common rail part.

Reference numeral 3 is a wheel support arm 3, and two pairs of the wheel support arms 3 are arranged on the outer periphery of the traveling apparatus body 1 in a radial direction orthogonal to each other, and the wheel support arms 3a, 3 of each pair are provided.
One end side of b is rotatably fixed to one end side of the traveling device body 1. 2 and 3 show one pair of wheel support arms 3
a, FIG. 4 and FIG. 5 show a part of the configuration of FIG. 1 so as to better show the configuration of the other pair of wheel support arms 3b, and the two wheel support arms 3a and 3b of each pair are opposed to each other. And the pairs of wheel support arms 3a, 3b are in the orthogonal position.

As shown in FIGS. 2 and 3, the pair of opposing wheel support arms 3a on one side are between the slider 2a located on the other end side away from the one end side of the traveling device body 1. The links 4a are connected. Therefore, when the slider 2a moves to the left side from the state of FIG. 2, the wheel support arm 3a interlocks and moves outward as shown in FIG.
When a moves in the opposite direction, it moves inward from the state of FIG. 3 to the state of FIG. From this, the slider 2a and the link 4a
Constitutes the above-mentioned interlocking mechanism. And slider 2
A spring (not shown) for urging the slider 2a to move to the left side in the drawing is provided between a and the traveling device main body 1, so that the two wheel support arms 3a interlock to move outward. Is biased by a spring. The structure and installation position of the spring are appropriate.

On the other hand, as shown in FIGS. 4 and 5, the pair of opposing wheel support arms 3b on the other side are linked with the slider 2b located on one end side of the traveling apparatus main body 1 by a link 4 therebetween.
b is connected. Therefore, when the slider 2b moves from the state of FIG. 4 to the right, the two wheel support arms 3b interlock and move outward as shown in FIG. 5, and when the slider 2b moves in the opposite direction, the state of FIG. Move inward to the state of. For this reason, the slider 2b and the link 4b constitute the above-mentioned interlocking mechanism as in the above-mentioned pair on the one side. In this pair, a spring (not shown) is provided between the slider 2b and the traveling device main body 1 to urge the slider 2b to the right in the figure. Therefore, the two wheel support arms 3b are provided on one side. Similar to the wheel support arm 3a,
It is urged by a spring to move in an outward direction in conjunction with each other.

As shown in the figure, each wheel support arm 3a,
3b is provided with traveling drive wheels 5 on the other end side thereof. The traveling drive wheel 5 has a large friction coefficient by an appropriate means such as baking urethane rubber on the outer circumference of a metal wheel. In each wheel support arm 3a, 3b, a worm wheel 6 is provided on the rotation shaft of the traveling drive wheel 5, and a motor 8 provided with a worm 7 screwed onto the worm wheel 6 is also provided. That is,
By driving the motor 8, the traveling drive wheels 5 can be rotationally driven through the worm 7 and the worm wheel 6 to travel.

A rotary potentiometer 9 is installed on each wheel support arm 3a, 3b at one end side of the traveling device main body 1 with respect to the traveling drive wheel 5, and the rotary potentiometer 9 has a rotary shaft. The angle measuring arm 10 is rotatably projected, and a spring (not shown) for biasing the angle measuring arm 10 to move outward is provided at an appropriate position, and the tip side of the angle measuring arm 10 is provided. Is provided with an angle measuring roller 11.

When the traveling device having the above-mentioned configuration is inserted into the pipe 12, the four traveling drive wheels 5 radially arranged on the outer periphery of the traveling device body 1 are attached to the wheel supporting arms 3a, 3a.
The traveling device main body 1 is supported at four points on the plane by being urged by a spring via 3b and being pressed against the inner wall of the pipe 12. At the same time, the angle measuring roller 11 moves the angle measuring arm 10
It is urged by a spring through the pressure contact with the inner wall of the pipe 12, and the output of the potentiometer 9 at this time corresponds to the angle of each angle measuring arm 10 with respect to each wheel supporting arm 3a, 3b. Become.

In this state, each wheel support arm 3
Drive the motor 8 installed on a and 3b to move the worm 7,
It is possible to travel by rotationally driving the traveling drive wheels 5 through the worm wheel 6, and the attitude of the traveling device main body 1 at this time can be detected by the output of each potentiometer 9, and therefore, By controlling the driving of the motor 8 by the output of the potentiometer 9, it is possible to travel while controlling the posture.

For example, FIG. 6 schematically shows the state of traveling on the straight pipe portion of the pipe 12 with respect to the wheel support arm 3a. The solid line in this figure shows the traveling device main body 1 on the central axis of the pipe 12. In this state, an angle formed by the angle measuring arm 10 and the wheel support arm 3a (the angle θ formed by the straight line 13 is used for convenience in the figure, but the angle reference is It can be set appropriately.)
Are equal for the pair of upper and lower wheel support arms 3a. That is, as shown in the figure, θu = θl.

A state indicated by a chain double-dashed line in the figure is a state in which only the traveling drive wheel 5 of the upper wheel support arm 3a is driven from the state of this solid line to move to the right in the figure. Thus, by moving only the upper traveling drive wheels 5,
The traveling device main body 1 is in an inclined state with the right side in the drawing facing downward. At this time, only the upper traveling drive wheels 5 have moved to the right in the figure, so that the upper and lower traveling drive wheels 5 move.
Corresponding to the extension of the distance between the upper and lower wheel support arms 3
The a is rotated outward by interlocking with the bias of the spring, which absorbs the extension of the distance. Since each angle measuring arm 10 constantly contacts the angle measuring roller 11 with the pipe wall of the pipe 12, the output of the potentiometer 9 is different between the upper and lower sides. That is, the above-mentioned upper and lower angles are θu ′> θl ′, as shown in the figure.

Therefore, by controlling the drive of the motor 8 so that the angle θu = θl on the upper and lower sides, the traveling apparatus main body 1 can be positioned on the central axis of the pipe 12 for traveling.

Further, if the drive of the motor 8 is controlled so as to have an angular relationship indicated by a chain double-dashed line in FIG.
The inside of the traveling device main body 1 that has been traveling inside can be slanted at a desired position, while the traveling device main body 1 was traveling on the central axis of the pipe 12 until then.

The posture control of the traveling apparatus main body 1 described above is independently performed in the same manner not only for the pair of wheel support arms 3a shown in FIG. 6 but also for the other pair of wheel support arms 3b orthogonal to these. By doing so, it is possible to perform posture control in two axial directions orthogonal to the traveling direction.

In the present invention, as described above, the wheel support arms 3a and 3b of each pair rotate to absorb the change in the distance between the pair of traveling drive wheels 5 at the opposing positions. Since the traveling drive wheels 5 can be driven to travel while controlling the above-mentioned angles of the respective wheel support arms 3a and 3b facing each other in each pair, a step in the pipe 12 is generated. Even if there is, it is possible to easily get over this step, and as shown schematically in FIGS. 2 and 3, 4 and 5, it is possible to run even if the diameter of the pipe 12 changes. Further, as shown in FIG. 7, even in the curved pipe portion, traveling can be performed while always orienting the traveling device body 1 in the axial direction of the pipe 12.

Referring to FIG. 7, a solid line indicates a state in which the traveling device main body 1 that has traveled without performing the individual control of the upper and lower traveling drive wheels 5 reaches from the straight pipe portion to the curved pipe portion. Since the angle measuring roller 11 preceding the traveling drive wheel 5 is located ahead of the curved pipe portion, the above angle is θu <θl. Therefore, if the angles are controlled so as to be equal, only the traveling drive wheel 5 on the upper side in the figure, that is, the outer side, is driven and moves to the right in the figure. In this operation, θu gradually increases and θl gradually decreases, and becomes equal when the outer traveling drive wheel 5 reaches the position of the chain double-dashed line in the figure. In this state, the traveling device main body 1 is oriented in the tangential direction on the central axis of the pipe 12.

The above is the operation in which the upper and lower traveling drive wheels 5 are made to travel without performing posture control by individual control. When individual control is performed from the straight pipe section, the angle measuring roller 11 is used. When the vehicle reaches the curved pipe portion, the posture control operation as described above is performed, and the traveling device main body 1 can be moved in the tangential direction on the central axis of the pipe 12 to pass through the curved pipe portion.

As in the case of the straight pipe portion, the curved pipe portion may be moved in a state in which the traveling device body 1 is inclined at an angle from the tangential direction of the central axis, or may be inclined as necessary. it can.

As can be seen from the above operation, the difference in the path lengths of the inner and outer traveling drive wheels 5 in the curved pipe portion is absorbed by the difference in the traveling distances of the respective traveling drive wheels 5, and no slip occurs. Therefore, the traveling drive wheel 5 can increase the frictional force in consideration of only the drivability, and thus can obtain a large traction force.

Further, the angle measuring arm 10 adjusts the biasing force of the spring so that the angle measuring roller 11 is brought into contact with the inner wall of the pipe 12 only for the angle measurement.
If the supporting force is not generated, the driving performance of the traveling drive wheels 5 can be further enhanced. Further, although the diameter of the angle measuring roller 11 is proper, as shown in the figure, by making it smaller than the diameter of the traveling drive wheel 5,
When the pipe 12 has a step, the overcoming performance is improved.

In the above embodiment, the traveling device body 1
Is configured as a rod-shaped body that constitutes a common rail portion of the sliders 2a and 2b, but the shape and the like are appropriate, and for example, by configuring it in a tubular shape, wirings can be passed through, a television camera, or the like. Monitoring sensors can be installed. In such a configuration, each slider 2a, 2b
The rail portions for use can be individually configured, and the interlocking mechanism described above can be realized by a mechanism other than such a slider mechanism.

[0036]

As described above, the present invention has the following effects. a. Rationalize the so-called CCV concept, in which four traveling drive wheels arranged in a plane in a radial pattern around the traveling device body are individually controlled according to sensor outputs corresponding to the posture of the traveling device body. Since it is an in-pipe traveling mechanism that has been specially incorporated, traveling performance is extremely high even on steps and curved pipe sections. b. The distance between the four traveling drive wheels is variable and is biased outward by a spring, so it is possible to cope with changes in the diameter of the pipe. c. Since the traveling drive wheel can be made large, it is easy to get over obstacles such as steps. d. Since the four traveling drive wheels are individually controlled, the posture can be appropriately controlled with a total of three degrees of freedom in one axis in the traveling direction and two axis directions orthogonal to the one axis. e. The shape of the traveling device main body can be cylindrical or the like, and the wiring can be penetrated, so-called Whole Stem Dri
A ve-type in-pipe mobile device can be configured.

[Brief description of drawings]

FIG. 1 is a perspective view showing a basic configuration of an example of a traveling device to which a traveling mechanism of the present invention is applied.

FIG. 2 is a side view showing a part of the basic configuration of FIG.

FIG. 3 is another side view showing a part of the basic configuration of FIG.

FIG. 4 is a side view showing another part of the basic configuration of FIG.

5 is another side view showing another part of the basic configuration of FIG. 1. FIG.

FIG. 6 is a schematic diagram showing a traveling operation in a straight pipe section of the basic configuration of FIG.

FIG. 7 is a schematic diagram showing a traveling operation in the curved pipe section of the basic configuration of FIG.

[Explanation of symbols]

 1 traveling device main body 2 (2a, 2b) slider 3 (3a, 3b) wheel support arm 4 (4a, 4b) link 5 traveling drive wheel 6 worm wheel 7 worm 8 motor 9 rotation potentiometer 10 angle measurement Arm 11 Angle measurement roller 12 Piping 13 Straight line

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[Procedure amendment]

[Submission date] May 8, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (5)

[Claims] 1. Two pairs of wheel support arms are radially arranged on the outer periphery of the traveling device main body, one end side of each wheel supporting arm is rotatably fixed to the traveling device main body, and each pair of wheels facing each other. The support arm is configured to be movable inward and outward by interlocking with an interlocking mechanism and is biased outward by a spring.Each wheel support arm has a traveling drive wheel at its other end and a drive mechanism therefor. In addition to the above, an angle measurement mechanism in which an angle measurement arm is rotatably projected is provided, and the angle measurement arm is provided with an angle measurement roller on the tip side and is urged outward in a pipe. 2. The interlocking mechanism is configured such that a rail portion is provided on the traveling device main body so that the slider can move in the propelling direction, and a link is connected between the pair of opposed wheel support arms and the slider. The in-pipe traveling mechanism according to claim 1, 3. The in-pipe traveling mechanism according to claim 2, wherein the rail portions have a common structure, and the sliders corresponding to each pair are movable to one end side and the other end side. 4. The in-pipe traveling mechanism according to claim 1, wherein the angle measuring mechanism is configured by rotatably projecting an angle measuring arm on a rotary shaft of a rotary potentiometer. 5. The in-pipe traveling mechanism according to claim 1, wherein the traveling device main body has a cylindrical shape.