JPS6319384B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for moving tubular objects such as various pipes within a pipe.

Manually perform various inspections for cracks, damage, abrasion, adhesion of foreign matter, deterioration of materials, etc. inside pipes, grasp the condition of pipe joints, and perform tasks such as laying cables inside pipes and transporting materials inside pipes. Robotization is a great hope for the future. In particular, when working inside pipes where there is no space for manual work, or when working inside pipes related to nuclear reactors where manual work is dangerous, this is an essential requirement that goes beyond simply streamlining the work and saving labor.

To do this, we must first develop a moving device that allows the robot itself to move freely within the pipe. Additionally, these mobile devices
I want it to work regardless of the pipe's orientation or internal undulations, and to have good tolerance for pipe inner diameter.

On the other hand, in the past, only moving devices using gravity were considered, and such devices can move inside pipes that are not horizontal, bent pipes, or even pipes with uneven pipe diameters. It was impossible to move.

In view of these circumstances, the present invention constantly detects the maximum inner diameter direction at each position in the length direction even for pipes with various changes in posture, shape, and pipe diameter.
The purpose was to provide a device that could move freely in the length direction, and the device itself was designed to be very simple and mechanically have the ability to flexibly follow the ups and downs inside the pipe. It's on.

Hereinafter, the present invention will be explained in accordance with each embodiment using the drawings,
explain in detail.

FIG. 1 shows the configuration of a basic embodiment of the present invention, which includes a pair of arms 1 and 2 of equal length, one end of which is pivoted to a common rotational fulcrum 3A to form a clamping mechanism. ing. In addition, in this embodiment, the rotation fulcrum 3A
A drive wheel 6 having a laterally movable structure, which will be described later, is also pivotally attached to the. That is, the rotation axis 6A of the drive wheel 6 is coaxial with the common rotation fulcrum 3A of the pair of arms.

Each free end 3B, 3C of the pair of arms is provided with an omnidirectional or flexible wheel 4, 5 as a follower wheel movable in all directions. is equipped with a clamping force generating mechanism 7.

The clamping angle θv formed by both arms 1 and 2 is variable depending on the degree of opening of both arms around the rotation fulcrum 3A, but normally, the clamping angle θv formed by the clamping force generating mechanism 7 mentioned above is variable. It is urged to be as small as possible by forces f and f. That is, as shown by the imaginary lines in FIG. 1, both wheels 4 and 5 are brought as close as possible,
Both arms 1 and 2 are arranged to lie along the bisector l of the angle θv as much as possible. As mentioned in advance, when both arms 1 and 2 are fully closed, the wheels 4 and 5
The distance Dmax between the ground contact surface or tread surface of the drive wheel 6 and the ground contact surface or tread surface of the drive wheel 6 is the maximum pipe inner diameter to which this moving device can be applied. In principle, the minimum pipe inner diameter can be tolerated up to an extremely small diameter by widening the clamping angle θv of both arms 1 and 2 to approximately 180°, but in practice, the clamping force generating mechanism 7 and other design matters determined by the degree of miniaturization of the specific configuration. However, there is no doubt that it has extremely large diameter tolerance in principle.

Next, in this embodiment, the wheels 10, which are used as the drive wheels 6 and are movable in the lateral direction or rollable, are
The wheel 10 that can also roll in the axial direction of the rotating shaft 11 (in this case, coaxial with the shafts 3A and 6A) will be described.

Since the present application does not relate to this laterally movable wheel itself, any specific configuration may be used as long as the desired function is satisfied, but as an example, a configuration example developed by the applicant will be described. will be explained with reference to FIGS. 2 and 3.

First, in the relatively basic configuration shown in the second figure, the wheel rim 1 is attached to the rotating shaft 11 via the support part 12 such as a cast spoke in the usual manner.
3 is fixed to the rotating shaft 11.

The tire section 14 attached around the wheel rim 13 is unique in that it is composed of a plurality of partial tires that are divided relatively finely in the circumferential direction, and these plurality of partial tires are arranged alternately. They are divided into the first and second groups 15 and 16.

The partial tires 15 in the first group are fixedly provided to the wheel rim 13 as in the previous wheels, but the partial tires 15 in the second group
6 is attached to the wheel rim 13 so as to be rotatable (arrow R) around an axis A that is approximately parallel to the tangential direction of the wheel rim at that portion. Therefore, in other words, it is designed to be able to rotate around an axis A that is substantially orthogonal to the wheel rotation axis 11, that is, in a lateral direction that is perpendicular to the direction of travel.

Therefore, when the fixed partial tire 15 is in contact with the ground, the driving characteristics are the same as those of conventional wheels, but the partial tire 16 that can rotate around the rim is
When it touches the ground, a unique characteristic appears, allowing it to roll horizontally, that is, in the direction of the rotation axis.

FIG. 3 shows another slightly more specific configuration example, and the components corresponding to those in FIG. 2 will be described with the same reference numerals. A bearing is used as the partial tire 16 that rotates around the bearing 1.
6 is rotatably attached to the center of the link 17. The end point of the link 17 is screwed or pin connected to the end point of the adjacent link to form a joint 18, and spokes 12, shown in the form of wire spokes in this case, are connected to this joint 18, and the wheel rotation shaft 11 is connected to the end point of the link 17. A fixation has been adopted.

In this way, a substantially circular polygonal rim 13 can be formed by a group of a plurality of links 17, and a suitable material such as rubber can be used to protect the exposed parts of the rim other than the bearings 16 and the joint joints 18. By forming the covering part 15 between the adjacent bearings 16, 16 using a suitable material, the covering part 15 can be used to have the same effect as the fixed partial tire 15 in the example shown in the second figure.

In any of the above examples, the material of each partial tire is a matter of choice depending on the application, and the rotating partial tire 16 may be in the shape of a pulley, belt, chain, etc.

Further, in the illustrated case, the fixed portion tires 15 and the rotating portion tires 16 are shown with approximately the same length in the circumferential direction and have approximately the same number, but the ratio of the numbers may be arbitrary. On the other hand, if desired, the circumferential length of the fixed partial tires 15 between the adjacent partial tires 16, 16 may be made as short as possible and/or may have a small diameter, so that substantially the ground contact surface of the entire wheel can be rotated. It can also be used by forming only the partial tires 16.

As mentioned above, wheels having other configurations can be used in the present invention as long as they have a lateral movement function.

In any case, the device shown in the first embodiment of the first embodiment using such a laterally movable wheel 10 as the driving wheel 6 has a diameter smaller than or equal to the maximum allowable inner diameter Dmax, as shown in FIG. It is used by putting it into the inner diameter pipe 8. Then, both arms 1 and 2 apply the biasing force f generated by the clamping force generating mechanism 7 according to the inner diameter of the pipe.
Therefore, due to the biasing force or clamping force f, the wheels 4 and 5 are pressed against one surface part 8b of the inner wall surface of the pipe, and on the other hand, due to the reaction force,
Since the drive wheel 6 is pressed against the other surface portion 8a facing in the diametrical direction, the device can eventually stand up within the pipe 8 and become stable. At this time, the direction XX connecting the centers of the wheels 4 and 5 generally coincides with the tube axis direction of that portion.

In addition, Fig. 5 shows the state in which the clamping mechanism is erected when viewed from the tube axis direction It may coincide with the maximum width to maximum inner diameter line L of the pipe internal cross section.

For example, if the wheels 4 and 5 are positioned on a line L' that deviates from the maximum width line L, not only are the wheels 4 and 5 omnidirectional, but the drive wheel 6 is also movable in the lateral direction as described above. Therefore, as shown by arrow C, as a result of the action of the clamping force, the direction changes within the plane and automatically moves to a position where it cannot shrink any further, that is, on the maximum width line L.

In this state, if the drive wheel 6 is rotated and stepped around the shafts 6A and 11 using a suitable drive source such as a step motor, the entire device can be moved along the tube axis direction X and at each position in the X direction. It is possible to detect the maximum width or the maximum inner diameter of each portion at each time while moving the device.

FIG. 6 shows a second embodiment of the invention.

In FIG. 1, the wheels provided on the fulcrum 3A side of arms 1 and 2 are the first wheel, the free ends 3B of each arm,
3C are the second and third wheels, respectively. In the previous embodiment, the first wheel is the laterally movable wheel 10 as the drive wheel 6, and both the second and third wheels are the wheels 10 as the driven wheels. It was directional wheels 4 and 5.

In this second embodiment, if the second wheel is the rear wheel in the traveling direction, this is the drive wheel 1 that is movable laterally.
0,6, and the first and third wheels are omnidirectional wheels 4,5.
It is said that However, omnidirectional wheels such as caster wheels generally have a common rotational fulcrum 3A for arms 1 and 2.
It is difficult to arrange the axis 4A coaxially with
In this embodiment, a link mechanism is employed based on the knowledge that a stable standing posture can be maintained if the wheels on the rotational fulcrum side are on the bisector l of the arm angle θv.

Hereinafter, to describe this, there are two link arms 19 and 20 of equal length connected at a common fulcrum 21, and the other end of each link arm is at a point equidistant from the common rotation fulcrum 3A of arms 1 and 2. The points 3A, 21, 22, 2 are pivoted to the parts 22, 23 of each arm 1, 2.
A four-bar link mechanism 25 is formed with 3 as a connection point.

One end of a drive wheel support rod 24 having its rotation center at the fulcrum 3A is connected to the center of the connection point 21 in this link mechanism via a known appropriate slide mechanism such as an elongated hole and a pin.

Therefore, the support rod 24 is always maintained on the line l bisecting the angle θv of the arms 1 and 2, regardless of changes in the angle θv between the arms 1 and 2. Therefore, the center 4A of the omnidirectional wheel 4 provided at the other end of this support rod also always rests on the outward extension l' of the angle bisector l, and the isosceles shape of the triangle 4A3B3C is guaranteed. Ru.

Therefore, in the device of this second embodiment as well, stable standing is ensured by always moving in the direction of detecting the maximum inner diameter of the tube, and the laterally movable wheel 10 attached to the free end of the arm 1 is Not only is it useful for its function, but if this is used as the drive wheel 6 and its rotation direction and rotation amount are controlled, it can similarly be driven in the tube axis direction.
In particular, if the laterally movable wheel 10 is the rear wheel as in this embodiment, the running stability will be excellent.

However, as can be inferred from this embodiment, there is no problem even if it is used as a front wheel, and the basic mechanism of the present invention can be satisfied.

FIG. 7 shows an embodiment in which stable movement within the pipe is possible even when the inner diameter of the pipe fluctuates significantly during travel. Figure a shows a modified version of the embodiment shown in the first diagram, and Figure b shows a modified version of the embodiment shown in the sixth diagram.
Incorporates a stretching device 26 whose effective length can be intentionally changed under the condition that the lengths are equal to each other.

Therefore, for large-diameter pipes, or in relatively large-diameter portions of the pipe in the longitudinal direction, the arms 1 and 2 should be extended to substantially increase the maximum permissible diameter Dmax shown in the first diagram. On the other hand, for small-diameter pipes or relatively small-diameter parts of the pipe in the length direction, arms 1 and 2 should be appropriately shortened to avoid making the angle θv too large.
It can be kept within an appropriate range.

Of course, it goes without saying that each relatively large diameter portion or small diameter portion is aligned in the direction of the maximum inner diameter.

In each of the embodiments described above, the specific configuration of each mechanical part or device can be designed using existing technology.
For example, the clamping force generator 7 may be a tension spring, the omnidirectional wheels may be an existing swivel caster arrangement, and the drive source for the drive wheels 6 may be a conventional electric motor or the like. Further, the stretching device 26 can be electrically operated, and furthermore, an automatic feedback loop can be set up using the information on the opening angle θv, or the clamping force can be controlled using the opening angle information. Of course, the amount of movement can also be detected from the amount of rotation of the drive wheels or the like.

As described above, according to the present invention, the "legs" of a robot for various pipe work can be configured in a generally planar structure with a small number of parts, and can be well adapted to the posture, shape, inner diameter, bending, etc. of the pipe. It is possible to provide a moving device having a maximum inner diameter detection function, which has great effects.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a basic embodiment of the present invention;
FIGS. 2 and 3 are explanatory diagrams of a configuration example of laterally movable wheels that can be used in the first illustrated embodiment, and FIGS. 4 and 5 are explanatory diagrams of the usage state of the present invention, respectively. FIGS. 6 and 7 are schematic configuration diagrams of other embodiments, respectively. In the figure, 1 and 2 are arms, 3A is a common rotational fulcrum, 3
B and 3C are rotation centers of wheels, 4 and 5 are omnidirectional wheels, 6 is a drive wheel that is movable laterally, 7 is a clamping force generation mechanism, 8 is a tube, 10 is a drive wheel that is movable in a lateral direction, 11 is a wheel rotating shaft, 12 is a spoke, 13 is a rim, 15 is a fixed partial tire, 16 is a partial tire rotatable around the rim, 17 is a link, 18 is a link joint, 19 and 20 are link arms, 21 ,2
Reference numerals 2 and 23 are connection points of four-bar links, 24 is a wheel support rod, 25 is a four-bar link mechanism, and 26 is an extension device.

Claims (1)

[Scope of Claims] 1. A pair of arms, one end of which is connected to a common rotational fulcrum, and the other end of which is a free end; a pinching force generating mechanism for applying force; a first wheel having a rotating shaft located on the bisector of the pinching angle on the one end side of the pair of arms; and a pinching force generating mechanism at each of the free ends of the pair of arms It consists of second and third wheels provided, and among the first, second, and third wheels, one is a drive wheel that is movable in the transverse direction with respect to the direction of forward rotation, and the remaining two are is an intra-pipe movement device characterized by omnidirectional wheels.