JPH07186937A - Mechanism mobile inside piping - Google Patents

Abstract

PURPOSE:To realize a subminiature mechanism mobile inside a piping provided with a continuously variable transmission mechanism and movable at high speed even inside a small bore diameter pipe line. CONSTITUTION:A movable mechanism inside a piping is provided with a motor 1, a ring shape structure 7 which makes a rotational motion by the motor 1, and a plurality of rotatable rollers 10 which are supported on the circumference of the ring shape structure 7 through an elastic arm 9 and brought in press contact with piping interior wall by inclining to the piping axial direction, while the ring shape structure 7 has the center of the piping used as its rotational center.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-pipe moving mechanism used in an apparatus for moving in a pipe and performing various inspections.

[0002]

2. Description of the Related Art Apparatuses that move in pipes and perform various inspections have been used in many cases so far in order to maintain and manage a large amount of piping system buried in chemical plants and underground buildings in cities. Types of equipment are being considered.

[0003]

However, many of the in-pipe moving mechanisms that have been prototyped so far are intended for pipes having a relatively large diameter, and are most often used.
The reality is that no mechanism that can move a pipe with a small diameter of an inch pipe or smaller has been realized. Further, when setting the in-pipe moving mechanism, it is necessary to match the reduction ratio of the drive system to the maximum load required. Therefore, when unevenness is expected during movement, or when a vertically rising motion is included, the reduction ratio must be set sufficiently high so that propulsion can be performed even under the worst conditions. However, if set in this way, there is a problem that the speed cannot be increased in a passage with good conditions such as in a horizontal and smooth pipe.

Further, the in-pipe moving mechanism that has been experimentally manufactured so far is located at the tip of the apparatus, and has a structure in which a wiring system for transmitting power or signals is routed. For this reason,
If the pipe is a bent pipe and it is attempted to be moved for a long distance, there is a problem in that the wiring system rubs against the pipe wall and cannot be propelled over a certain distance. The present invention has been made in view of such conventional problems, and has a continuously variable transmission mechanism.
It is an object of the present invention to provide an ultra-compact in-pipe moving mechanism that can move at high speed even in a small-diameter pipe line of inch or smaller.

Another object of the present invention is to provide an in-pipe moving mechanism which enables long-distance movement without the wiring system interfering with the pipe wall.

[0006]

In order to solve such a problem, in a pipe moving mechanism according to the present invention, a motor, an annular structure rotating by the motor, and an elastic body around the annular structure are interposed. And a plurality of rotatable rollers that are supported and supported by pressure on the inner wall of the pipe while inclining to the pipe axial direction and in pressure contact with each other, and the annular structure has a substantially pipe center as the center of rotation.

The in-pipe moving mechanism further includes a transmission mechanism for transmitting the rotational movement from the motor to the annular structure, and the transmission mechanism and the annular structure constitute a planetary gear mechanism.
While making the annular structure the ring gear of the planetary gear mechanism,
The transmission mechanism includes a frame provided on one side of the annular structure, a sun gear having a center of rotation as the center of piping, and a planetary gear that is rotatably attached to the frame and meshes with the sun gear and the ring gear. A through hole formed in the axial direction of the pipe can be provided in a portion of the frame where the planetary gear is not attached.

Further, it is also possible to connect two sets of the moving mechanism in the pipe through a universal joint and to set the rotational movement of the pipe center of each annular structure in reverse.
Furthermore, it is possible to connect a plurality of in-pipe moving mechanisms along a wiring system that transmits power or signals.

[0009]

A plurality of rollers mounted via an elastic body around an annular structure which is rotated by a motor are rotated while being pressed against the inner wall of the pipe while being inclined to the pipe axial direction. As a result, the roller causes a spiral rotation motion as if to advance a screw to propel the inside of the pipe.

Since it is based on the spiral rotary motion, the propulsion is fast and the rotary motion with the center of the pipe as the center of rotation is used, so that the mechanism can be downsized. Since the roller is supported by the annular structure via the elastic body, when the propulsion resistance increases, the inclination angle of the roller, that is, the pitch of propulsion automatically decreases, and the thrust increases in a continuously variable transmission. It has a continuously variable function.

By forming the planetary gear mechanism with the transmission mechanism and the annular structure, the through hole can be provided in the frame of the transmission mechanism. By using this through hole to penetrate the wiring system in the axial direction of the pipe moving mechanism, the pipe moving mechanism can be attached to any part of the wiring system, and the wiring system can interfere with the pipe wall. Can be prevented. Connect two sets of in-pipe moving mechanism via universal joint,
By setting the rotational movement of the pipe center of the annular structure in the opposite direction, it is possible to balance the turning force applied to the frame and prevent the frame from turning.

Further, by connecting a plurality of in-pipe moving mechanisms through a universal joint, the thrust can be increased and the bent pipe can also be moved for a long distance.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall perspective view of a pipe moving mechanism according to the present embodiment. In the figure, 1 is a small DC motor,
The output shaft of the motor 1 is connected to the power transmission shaft 3 via the universal joint 2.

A transmission mechanism T and an annular structure 7 are arranged at the tip of the power transmission shaft 3. An enlarged perspective view of the transmission mechanism T and the annular structure 7 is shown in FIG. The transmission mechanism T and the annular structure 7 constitute a planetary gear mechanism, and the annular structure 7 is a ring gear in which gears are formed inside. The transmission mechanism T includes a sun gear 4, a frame 5, and a planetary gear 6.

The sun gear 4 is integrally connected to the power transmission shaft 3. The frame 5 is provided on one side of the annular structure 7, and a planetary gear 6 is rotatably mounted on the frame 5, so that the gear meshes with the sun gear 4 and the ring gear of the annular structure 7. And transmits the rotation of the sun gear 4 to the annular structure 7. Further, a wiring system through hole 8 is formed in a portion of the frame 5 where the planetary gear is not attached.

Around the annular structure 7, a plurality (three in this embodiment) of elastic arms 9 are attached with rotational symmetry at equal intervals. Each elastic arm 9 is shaped so as to draw a spiral around the annular structure 7. A roller 10 is rotatably supported at the tip of the elastic arm 9. The in-pipe movement mechanism configured as described above has a trunk trunk shape and moves in the pipe. To explain such an operation, the rotation from the small DC motor 1 is transmitted to the sun gear 4 by the power transmission shaft 3 and is transmitted to the annular structure 7 via the planetary gear 6. Then, when the annular structure 7 turns, the roller 10 supported by the spiral elastic arm 9 advances while being pressed against the inner wall of the pipe while being inclined and in contact with the pipe axial direction, thereby causing a motion as if to advance a screw. Promote. Since the spiral rotary motion is performed in this way, the propulsion is fast, and since the rotary motion with the center of the pipe as the center of rotation is used, the size can be reduced, and the pipeline having a small diameter of 2 inches or less can be moved. be able to.

Further, by supporting the roller 10 by the elastic arm 9, the in-pipe moving mechanism can easily follow the unevenness in the pipe and realize a stable propulsion motion. Further, by supporting the roller 10 by the elastic arm 9, the in-pipe moving mechanism has a continuously variable transmission mechanism. This principle will be described with reference to FIG. FIG. 3 is an explanatory diagram showing the relationship between the annular structure 7, the elastic arm 9, and the roller 10. The mounting angle of the elastic arm 9 of the annular structure 7 is θ,
Assuming that the bending angle of the elastic arm 9 is φ, the frictional force applied to the roller 10 is f, the rotational force of the annular structure 7 is F, and the load is W, F = fsin (θ −φ) (1) W = fcos (θ−φ) (2).

The bending angle φ of the elastic arm 9 is defined by the length l of the elastic arm 9, the longitudinal elastic modulus E, and the moment of inertia of area I.
Using

[0019]

[Equation 1] Is expressed as From equations (1) and (2), F = Wtan (θ−φ) (4), and the motor characteristics are: motor terminal voltage V, motor circuit resistance R, motor constant K, magnetic flux ξ, torque T
Then,

[0020]

[Equation 2] Therefore, the velocity v in the propulsion direction is

[0021]

[Equation 3] Becomes Also, from equations (2) and (3)

[0022]

[Equation 4]

It becomes A graph showing the relationship between the speed v in the propulsion direction and the load W from the above equations (6) and (7) is shown in FIG.
4 is a graph showing the relationship between the rotational force F and the load W.
It is (b). As can be seen from this graph, the larger the load, the lower the propulsion speed, and the smaller the load, the higher the propulsion speed. That is, if the load is light, the inclination of the elastic arm 9 is large, but when the load is large, the compressive force acting on the elastic arm in the axial direction of the pipe increases, so that the elastic arm 9 is gradually pushed to decrease the inclination angle and increase the reduction ratio. Show. Thus, the load-sensitive continuously variable transmission function is configured.

In FIG. 4, the chain line is θ = 50 ° (two-dot chain line) and θ = 3 when the elasticity of the elastic arm is lost.
It is a corresponding graph when it is fixed at 0 ° (dashed line). Comparing with these, it is well understood that in this embodiment, from the effect of the deformation of the elastic arm, a high speed propulsion motion to a high power motion can be generated. Next, FIG. 5 is a perspective view of a pipe moving mechanism according to a second embodiment of the present invention.

In this embodiment, the in-pipe moving mechanism A of FIG. 1 and another in-pipe moving mechanism B are connected by a universal joint 11. Specifically, the frame 5 of the in-pipe moving mechanism B is connected to the casing, which is a non-rotating portion of the motor 1 of the in-pipe moving mechanism A, via the universal joint 11. Then, the rotation directions of the motors 1 of the in-pipe moving mechanism A and the in-pipe moving mechanism B are set to be opposite to each other.

In order to cause the spiral propulsion motion described in the previous embodiment, it is necessary to support the frame 5 so as not to rotate. For this reason, generally, it is conceivable that the roller 10 is pressed against the inner wall of the pipe so as to prevent the turning so that the roller 10 can freely roll in the axial direction of the pipe. However, in this method, the turning of the frame 5 is completely prevented. Is difficult. Therefore, in the present embodiment, the rotation of the roller in the in-pipe moving mechanism A and the rotation of the roller in the in-pipe moving mechanism B are reversed to balance the turning force applied to each frame 5, and as a result, the frame 5 is rotated. It prevents the turning of.

Further, the two sets of in-pipe moving mechanisms A and B shown in FIG.
A through the universal joint 11 in order,
By connecting with B, A, B, ..., The whole is configured so as to have a nodule trunk shape. In this way, the thrust can be increased and each roller 10 follows the shape of the inner wall of the pipe, so that the curved pipe portion can also move.

In each of the above embodiments, the wiring system can be arranged along the in-pipe moving mechanism by penetrating the wiring system through the wiring system through hole 8. Even when a plurality of in-pipe moving mechanisms are connected, the wiring system can be wired along the drive system by passing the wiring system through the respective through holes 8 for the wiring system. Therefore, the pipe moving mechanism can be arranged not only in the tip portion of the device to be inserted into the pipe but also in any portion, and a plurality of connected pipe moving mechanisms can be arranged in the entire device. It is also possible to move a long distance.

In the above embodiments, the rotation from the motor 1 is transmitted to the sun gear 4. However, the invention is not limited to this, and the rotation from the motor 1 may be transmitted to the planetary gear 6. You can also Further, the universal joint 2 and the power transmission shaft 3 are provided between the motor 1 and the transmission mechanism T.
Although the motor 1 and the transmission mechanism T are directly connected to each other, the invention is not limited to this.

[0030]

As described above, according to the present invention,
A motor, an annular structure that rotates by the motor, and a plurality of rotatable rollers that are supported around the annular structure via an elastic body and are pressed against the inner wall of the pipe while inclining to the pipe axial direction and inclined. Since the circular structure makes the center of rotation about the center of the pipe, the roller causes a spiral rotation motion as if to advance a screw to propel the inside of the pipe, so that the propulsion is fast and the center of rotation is the center of rotation. By using, it is possible to achieve miniaturization.

Further, since the roller is supported by the annular structure via the elastic body, the roller can easily follow the irregularities in the pipe, and a stable propulsion motion can be realized. Further, since the roller is supported by the annular structure through the elastic body, it is possible to provide a continuously variable transmission function. Also, a through hole can be provided in the frame of the transmission mechanism, and by utilizing this through hole to penetrate the wiring system in the axial direction of the in-pipe movement mechanism, any part of the wiring system can be moved in the pipe movement mechanism. Can be installed, and the wiring system can be prevented from interfering with the pipe wall and can be moved over a long distance.

By connecting two sets of in-pipe moving mechanisms via a universal joint and setting the rotational movement of the pipe center of the annular structure in the opposite direction, the turning force applied to the frame is balanced and the turning of the frame is prevented. Occurrence can be prevented. Further, by connecting a plurality of in-pipe moving mechanisms via a universal joint, it is possible to move a long distance including a bent pipe.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a first embodiment of an in-pipe moving mechanism of the present invention.

FIG. 2 is an enlarged perspective view of the transmission mechanism and the annular structure shown in FIG.

FIG. 3 is an explanatory diagram of the principle of a continuously variable transmission mechanism.

FIG. 4A is a relationship diagram of speed and load in the propulsion direction, and FIG. 4B is a relationship diagram of rotational force and load.

FIG. 5 is an overall perspective view showing a second embodiment of the in-pipe moving mechanism of the present invention.

[Explanation of reference numerals] 1 motor T transmission mechanism 4 sun gear 5 frame 6 planetary gear 7 annular structure 8 through hole for wiring system 9 elastic arm 10 roller 11 universal joint

Claims (4)

[Claims] 1. An in-pipe moving mechanism that moves in a pipe, a motor, an annular structure that rotates by the motor, and an annular structure that is supported around an annular structure via an elastic body and is arranged in an axial direction of an inner wall of the pipe. And a plurality of rotatable rollers that are inclined and pressed against each other, and the annular structure has a substantially pipe center as a center of rotation. 2. The in-pipe moving mechanism further includes a transmission mechanism that transmits the rotational movement from the motor to the annular structure, and the transmission mechanism and the annular structure constitute a planetary gear mechanism.
While making the annular structure the ring gear of the planetary gear mechanism,
The transmission mechanism includes a frame provided on one side of the annular structure, a sun gear having a center of rotation as the center of piping, and a planetary gear that is rotatably attached to the frame and meshes with the sun gear and the ring gear. The in-pipe moving mechanism according to claim 1, wherein a through hole is provided in a portion of the frame where the planetary gear is not attached, the through hole being provided in the axial direction of the pipe. 3. A pipe moving mechanism for connecting two sets of the pipe moving mechanism according to claim 2 via a universal joint, and setting the rotational movement of the pipe center of each annular structure in reverse. 4. An in-pipe moving mechanism for connecting a plurality of the in-pipe moving mechanisms according to claim 3 along a wiring system for transmitting power or a signal.