JPS6370107A - Apparatus for inspecting interior of pipe - Google Patents

Abstract

PURPOSE:To obtain accurate judge information by eliminating the measuring error of a pipe, by contracting the diameter of an enclosure in a center axis direction by the action of a link mechanism when external pressure is applied to the enclosure and restoring the diameter of the enclosure when the external pressure is removed. CONSTITUTION:A slider 31 is mounted to the center shaft 30 of an inspection apparatus so as to freely slide in the axial direction. The leading end of one arm 35 constituting a link mechanism 34A is mounted to said slider 31 in a freely revolvable manner and the leading end of the other arm 36 constituting the link mechanism 34A is mounted to a part of the center shaft 30 in a freely revolvable manner. The slider 31 is energized in the direction reverse to an arrow B by a spring 36 and acts so that the leading ends of the arms 35, 36 approach with each other. That is, the link mechanism acts in a direction separating plates 401, 402 from the center shaft 30.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an in-pipe inspection device used for inspecting cable pipes, gas pipes, water pipes, sewage pipes, and the like.

(Prior Art) Various types of pipe inspection devices have been developed depending on the purpose of the inspection. Among them, when a cable is buried in a buried pipe, there is a device that inspects whether the cable can be guided in advance. This is to check for pipe diameter reduction due to bending or deformation of the pipe, adhesion of stones, concrete, etc. inside the pipe, and to check for external pressure being applied to the cable due to the reduction in pipe diameter, and to use this as a basis for making decisions regarding cable installation. .

As this type of inspection device, there is a device disclosed in Japanese Patent Publication No. 60-21321. As shown in FIG. 7, in this device, a guide arm 12 that elastically projects in the radial direction is attached to the outer peripheral rear part of the 1lPI meter main body 10, and a roller 13 is attached to the tip of this guide arm 12. . Further, a telescoping arm 15 constituting a link mechanism 14 is protruded from the outer peripheral front part of the measuring instrument main body 10, and a roller 16 is attached to the protruding part.
is installed. By expanding and contracting the link mechanism 14 according to the diameter of the pipe 20, the core 18 of the differential transformer 17 can be driven, and the change in electrical output is extracted as pipe diameter information.

(Problems to be Solved by the Invention) According to the conventional device, as shown in FIG. 8, for example, in the bending tube 21, the positions of the rollers 16, 16 do not match accurately in the radial direction of the tube. , there is a problem that accurate tests cannot be obtained. Furthermore, when measuring not only a bent tube but also a bent tube section, there is a problem in that the rollers 16, 16 do not line up on a line extended from the center of curvature, making it impossible to obtain an accurate measurement of the tube diameter.

Further, FIG. 7(B) shows the above-mentioned inspection device from the direction of the pipe axis. Since the arm is configured to protrude in a direction radiating from the main body, foreign objects (concrete, stones, etc.) can be detected between the rollers 16 as shown in the figure. etc.) 22, it cannot be detected and may become a hindrance when inserting the cable later.

Therefore, when a cable is actually laid inside a pipe, the external pressure applied to the cable may be a fixed result.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a pipe inspection device having a structure capable of eliminating pipe measurement errors and obtaining accurate judgment information.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a slider portion that surrounds a central axis and is slidable in the axial direction, a first arm tip is attached to the slider portion, and a second arm tip is attached to the slider portion. is rotatably attached to the shaft, and the first. A connecting portion of a second arm includes a plurality of unit link portions protruding from the axis in a radial direction, a portion of an inner wall is connected to each of the connecting portions, and a cylindrical shape surrounds the plurality of unit link portions in a direction around the central axis. It consists of a plurality of plates forming a shape, the axial sub-part of each plate consisting of an envelope of overlapping structure.

(Function) With the above means, when external pressure is applied to the envelope, the diameter of the envelope is reduced in the central axis direction by the action of the link mechanism, and when the external pressure is removed, the diameter of the envelope is reduced. It operates to restore the diameter. This device has a cylindrical outer diameter, and can accurately detect the minimum diameter when inspecting bent tubes, bent tubes, etc., and can also detect foreign objects such as concrete or stones inside the tube. This allows the minimum diameter of this portion to be reliably detected without being overlooked.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.
) is a cross-sectional view, and the same figures (B) and (C) are diagrams showing examples of external shapes. 30 is the central axis of the inspection device, and this central axis 30
A slider 31 is attached to the slider 31, and the slider 31 is slidable in the axial direction. The tip of one arm 35 constituting the link mechanism (11434) is rotatably attached to this slider 31. The tip of the other arm 36 constituting the link mechanism 34A is rotatably attached to the - portion of the central axis 30. The connecting portions of the arms 35 and 36 are arranged in a direction radiating from the central axis 30, and this portion is connected to a part of the inner wall of the plate 401.

The tips and connecting portions of the arms 35 and 36 are rotatably supported by a shaft and constitute a unit link machine groove. Such unit link mechanisms further include 34B, 34C, 3
As shown by 4D, it has multiple stages, radiates around the central axis 30, and supports a plurality of plates.

The unit link mechanisms 34B and 34D support the plate 402, and the unit link mechanism 34A134C supports the plate 401. Although only four unit linkage sections are shown in the figure, they are also provided at other angular positions and support other plates.

Here, the slider 31 is biased by the spring 36 in the direction opposite to the arrow B shown in the figure, and acts so that the tips of the arms 35 and 36 approach. In other words, the link mechanism is
It acts elastically to move the plates 401, 402 away from the central axis 30.

The envelope 407 formed by the plates 401, 402, 403 to 406 is, for example, shown in FIG.
As shown, it is approximately cylindrical.

Further, plates 401 to 4 constituting the envelope 407
06, as shown in FIG. 2, the axial side portions are arranged so as to overlap each other with a step difference, and the diameter of the envelope 407 is configured to expand and contract smoothly. The stepped portion functions as a stopper when the envelope 407 is contracted to its smallest diameter, and protects the inside.

Furthermore, FIGS. 3(A) and 3(B) show a part of the envelope of FIG. 1(C), which can be used when there is a foreign object in the axial gap between the plates. This was done to ensure reliable detection.

That is, when a foreign object passes in the direction of arrow X, the protrusion 0
6A collides with a foreign object. As a result, the diameter of the envelope is reduced, but since the protrusion 06A enters the opposing recess 05A, there is no problem in reducing the diameter. Although only one location is shown in the figure, as can be seen from FIG. 1(C), detection supplementary sections 01A to 04A as shown in FIG. 3 are provided at multiple locations between the plates.

FIG. 4 shows an example of the unit link mechanism section 34C134D shown in FIG. 1 in more detail, and shows a structure for transmitting the movement of the slider 35 to the core 51 of the differential transformer 50.

The slider 35 is movable in the illustrated arrow YZ direction by the action of the link mechanisms 34C and 34D. slider 3
5 is connected via a pin 61 to a drive piston 62 housed in the hollow of the central shaft 30. Therefore, if the slider 35 moves in the direction of the arrow Y-Z in the figure, the drive piston 62 also moves in the direction of the arrow Y-Z in the figure. This drive piston 62 has a core 51 of the differential transformer 50.
The tip is attached by screw means. Furthermore, the core 51 guide portion of the differential transformer 50 and the drive piston 6
A spring-shaped waterproofing device 63 is attached between the ends of the core 51 and the core 51 to make the core 51 waterproof.

FIG. 5 is an explanatory diagram showing the state in which the apparatus of the present invention is used.

Figure (A) shows a pipe diameter measurement method when no differential transformer is installed inside the central shaft.

The device 80 is inserted into the underground pipe 70 and pulled by the winch 73 via a wire. At this time, the winch 73 has
A torque limiter 72 is provided, and its output is recorded by, for example, a recording device.

In other words, as the diameter of the tube changes and a traction load is applied to the device 80, the diameter of the tube becomes smaller. Therefore, the recording device can record changes in the diameter of the tube according to the amount of winding of the wire.

FIG. 5(B) shows the device 80 of the present invention as shown in FIG.
shows the method for inspecting the inside of a pipe when it is equipped with a differential transformer. The device 80 of the present invention has a winch 73
The pipe travels inside the underground pipe 70 while being towed by the pipe, and the pipe diameter 71111 constant information is supplied to a recording device 75 electrically connected to the differential transformer. Note that various embodiments are possible as the recording device. By recording the output of the differential transformer or the output of the torque limiter with a pen recorder or the like according to the amount of cable feed or the winding amount, the deformation position and deformation opening of the tube can all be determined. The amount of cable feeding or winding can be measured by measuring the rotation detection pulse of the winch or guide roller.

FIG. 6 shows a simplified version of the device 8o of the present invention. In the case of the device 80 of the present invention, the envelope is configured in a cylindrical shape and has a structure that is freely expandable and contractable in the radial direction. Therefore, even if the pipe line of the pipe 70 is bent, when passing through this part, the pipe inner diameter dimension and the pressure from the pipe inner wall can be determined in the same state as when actually passing through the table. Therefore, if the cable is measured using the device of the present invention before laying the cable,
It can be used as a basis for determining appropriate cable installation and pipe repair.

[Effects of the Invention] As described above, the present invention can provide a pipe interior inspection device having a structure that can eliminate the 1llj determination error of the pipe and obtain accurate judgment information.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view and an external perspective view showing an embodiment of the present invention, Fig. 2 is an explanatory diagram of the operation of the inventive device, Fig. 3 is a diagram showing a part of the inventive device, and Fig. 4 is a diagram illustrating the operation of the inventive device. A sectional view showing another embodiment of the invention, FIG. 5 is an explanatory view showing how the inventive device is used, FIG. 6 is an explanatory view showing an example of the operation of the inventive device, and FIG. 7 is a conventional FIG. 8 is an explanatory diagram of the structure of the pipe inspection device, and FIG. 8 is an explanatory diagram of the operation of the conventional pipe inspection device. 30... Central axis, 31.35... Slider, 34A
~34D... Unit link machine + i/j section, 35.36.
...Arm, 36...Spring, 401-406.
...Plate, 407...Envelope, OIA, 02A,
03A. 04A...Detection supplementary section, 50...Differential transformer, 5
1... Core, 62... Drive piston.

Claims (6)

[Claims] (1) A slider part that surrounds a central axis and can freely slide in the axial direction, a first arm tip is attached to this slider part, a second arm tip is rotatably attached to the shaft, and the first,
a plurality of unit link mechanisms in which the connecting portions of the second arm protrude in a radial direction from the axis; and the connecting portions are each attached to a part of an inner wall, and surround the plurality of unit link mechanisms in a direction around the central axis. 1. A pipe inspection device comprising: an envelope made up of a plurality of plates forming a cylindrical shape. (2) The pipe inspection device according to claim 1, wherein the plurality of plates have a structure in which the axial side portions of adjacent plates overlap each other with a step difference. (3) In the plurality of plates, the axial side portions of adjacent plates face each other with uneven portions, and the uneven portions fit together when the diameter of the envelope is reduced. An in-pipe inspection device according to claim 1, characterized in that: (4) A predetermined unit link mechanism unit drives a slider mounted around the central axis in the axial direction of the central axis. Inspection equipment. (5) The center shaft has a hollow space, and a differential transformer is disposed therein, and the core of the differential transformer is connected to the slider via a drive piston. An in-pipe inspection device according to claim 4. (6) A bellows-shaped waterproofing device is provided between the core guide portion of the differential transformer and the drive piston to prevent exposure of the core and prevent water from entering from the outside. An in-pipe inspection device according to claim 5, characterized in that: