JP3356261B2 - Rotary tube camera and cable length measurement method for rotary tube camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary in-pipe camera having a rotary drum in which a coil spring containing a long cable having a camera unit at the end is wound and housed. Further, the present invention relates to a rotary in-pipe camera and a cable length measuring method in a rotary in-pipe camera, wherein the amount of movement of a coil spring to be fed is obtained from the amount of rotation of guide means which rotates with the movement of the coil spring.

[0002]

2. Description of the Related Art For example, in order to check the inner wall of a pipe for damage, a flexible coil spring containing a long cable with a camera unit mounted at the end is fed into the pipe and run, and the damaged portion is imaged. An in-pipe traveling camera that can be captured by a camera is used. That is, as shown in FIG. 6, in this in-pipe traveling type camera, a flexible coil spring 1 in which a long cable having a camera unit mounted at the end is provided.
Is wound around the rotary drum 2 and when the coil spring 1 is fed into the tube, the length of the coil spring 1 pulled out is monitored to determine a damaged portion in the tube. At this time, as means for knowing the pulled-out length of the coil spring 1, (1) a method of marking a scale on the coil spring 1, (2) marking the current position on the coil spring 1 at the time of insertion, and extracting After that, there is a method of measuring the distance to the position.

[0003]

However, according to the method (1), the scale moves away while the tube is being used several times because the inner surface of the coil spring moves while rubbing the inner wall of the tube during use. . On the other hand, the method (2) is not an effective method because the operation is complicated and the length is not known on the spot. The present invention has been made in order to improve such a problem, in a rotary in-pipe camera having a rotary drum wound and accommodated a coil spring containing a long cable having a camera unit at the tip,
In order to grasp the damaged portion of the pipe, the amount of movement of the coil spring fed, plan to rotate along with the movement of the coil spring
An object of the present invention is to provide a rotary in-pipe camera and a cable length measuring method in the rotary in-pipe camera, which are determined from the rotation amount of the inner means .

[0004]

In order to solve the above-mentioned problems, the present invention captures an image of a damaged portion in a pipe at the tip.
That the coil spring interior a long cable with a camera unit, while fed into the tube, winding from the tube
A rotary drum for containing, inside the rotating drum, by rotating the rotating drum, provided with a small drum for winding the coil spring, the coil of the small drum
A rotating drum and small
Guides the coil spring, which rotates independently of the drum
Guide means provided with that, it provided a structure with rotation detector to operate following the rotation of the guide means. In the above-described rotary in-pipe camera, when the coil spring is pulled out of the small drum via the guide means to the outside of the rotary drum or wound around the small drum, the rotation amount of the rotating guide means is detected, and the rotation amount is detected. The movement amount of the coil spring can be obtained from the detection signal. The present invention also provides a coil spring that uses a unique conversion value when deriving the moving distance of the coil spring from the detection signal concerning the amount of rotation of the guide means, when sending out the coil spring, and when winding the coil spring. Can be obtained. Further, the present invention provides a method for deriving a moving distance of a coil spring from a detection signal relating to a rotation amount of a guide means, when feeding the coil spring, and when winding the coil spring, a plurality of coil springs are provided according to the winding amount of the coil spring. Apply the conversion value,
The moving distance of the coil spring can be determined. Further, according to the present invention, when deriving the moving distance of the coil spring from the detection signal relating to the rotation amount of the guide means, the current feeding amount is stored, the converted value is continuously changed and applied, and the coil spring is moved. The travel distance can be determined.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a rotary in-pipe camera and a cable length measuring method in the rotary in-pipe camera according to the present invention. FIG. 1 shows a cable accommodating device 10 in a rotary in-pipe camera. The cable accommodating device 10 is introduced into a pipe (not shown) to be inspected, and a state inside the pipe is captured by an image. It has a function of winding up and accommodating a flexible coil spring 11 in which a long cable having a camera unit is provided. That is, the cable accommodation device 10 is
In the drawing, a rotating drum 13 is rotatably supported with an axis oriented in a horizontal direction as a rotating axis. A small drum (to be described later) for winding and housing the spring 11 is provided. The rotating drum 13 has a conical outer shape near the one end of the portion supported by the base 12, that is, a side on which the coil spring 11 is pulled out and wound up, and a cylindrical outer shape near the other end. This rotating drum 13
A motor 14 as a power source is disposed on the other end of the rotary drum 13 so as to apply a rotating power to the rotary drum 13 via a transmission gear mechanism 15. The power of the manual operation handle 16 is transmitted to the transmission gear mechanism 15 so that the rotary drum 13 can be rotated by manual operation. That is, the power from the motor 14 and the manual operation handle 16 as these power sources is
Power transmission means (not shown) is indirectly connected to the transmission gear mechanism 15 according to the use situation.

[0006] The cable accommodating device 10 having the above configuration
In the following, the rotary drum 13 will be described in more detail. As shown in FIG. 2, the pulled-out coil spring 11 is wound and housed in the outer cylindrical shape near the other end of the rotating drum 13 by rotating the rotating drum 13 by the motor 14 or the manual operation handle 16. A small drum 17 is disposed. In the rotary drum 13, a guide blade 18 as guide means is rotatable separately from the rotary drum 13 and the small drum 17 on an end surface side of the small drum 17 near the insertion / reception side of the coil spring 11. Blades 19 for preventing the coil spring 11 from collapsing are provided at approximately 120 ° clockwise and counterclockwise with respect to the blade 18. As shown in FIG. 3, the guide blade 18 is provided with a guide frame 20 as a guide means when the coil spring 11 passes therethrough. Spring 11 is connected to the small drum 1
7 and is guided and wound so as not to disperse around the small drum 17.

A rotation detector 21 (for example, a rotary encoder or a tachometer) that moves following the rotation of the guide blade 18 is mounted inside the small drum 17. The rotation detector 21 (hereinafter, rotary encoder 21) converts the amount of rotation (rotation angle) of the guide blade 18 into a digital code (pulse). The rotation angle is determined. Such a rotary encoder 21
For example, a device that outputs 500 pulses per rotation can be applied. The rotary encoder 21 as described above is connected to the rotation shaft 23 of the guide blade 18 rotatably mounted via a bearing 22 on the end face side of the small drum 17 near the insertion / reception side of the coil spring 11 as described above. (See FIG. 4). The signal extracted from the rotary encoder 21 is a signal line 2
4 to an inspection device (not shown). That is, the signal line 24 is first connected to the rotating drum 1
3 is a circular plate 26 provided with a projection 25 on its cylindrical end face.
In the drum gear 27 that constitutes the transmission gear mechanism 15 attached via a connector, a connector 28 provided at the center of the disk 26 is connected to a connector 29 of the signal line 24 on the rotary encoder 21 side, and then the disk The lead wire 3 from the connector 28 is attached to a slip ring 30 which is a rotary contact provided on the opposite surface of the drum gear 27 provided with
1 is connected, and the conductor 32 from the fixed side of the slip ring 30 is connected to the inspection device to transmit a signal. The fixed terminal side of the slip ring 30 is supported by a holding spring 33.

In the cable accommodating device 10 constituting the above-described rotary in-pipe camera, the coil spring 11 is inspected from the rotary drum 13 by a pushing means (not shown) to the camera unit (not shown) on the distal end side of the coil spring 11. It can be introduced into a pipe to be damaged, and a damaged portion in the pipe can be captured with an image. Guide blade 1 for guiding coil spring 11 when coil spring 11 is pulled out from rotary drum 13
Since the guide frame 20 is pushed by the coil spring 11, the guide blade 18 rotates. On the other hand, the motor 14 or the manual operation handle 16 selected by the power switching means
Is started, and the rotating drum 13 is rotated to rotate the small drum 17.
When the coil spring 11 is pushed into the rotary drum 13 in a state where the coil spring 11 is easily pulled back from the inside of the pipe, a force is exerted on the guide frame 20 of the guide blade 18 by the coil spring 11, Feather 1
Since the coil spring 8 guides the coil spring 11 toward the small drum 17 while rotating, the coil spring 11 is wound around the small drum 17. In addition, the guide blade 18 is a small drum 1
Even if the coil 7 rotates, if the coil spring 11 does not move back and forth, the coil spring 11 does not rotate because the coil spring 11 is in a restrained state. When the coil spring 11 moves back and forth as described above, the guide blade 18 rotates by an angle corresponding to the moving distance. On the other hand, even if the rotary drum 13 is rotated, if the coil spring 11 does not move, the guide blade 18 rotates together with the rotary drum 13, so that the rotary encoder 21 does not rotate, so that no signal is output. Absent.

When the rotary encoder 21 rotates together with the guide blade 18 by moving the coil spring 11,
A signal relating to the rotation angle is output from the rotary encoder 21, and the amount of feed of the coil spring 11 can be obtained by converting the detection signal. That is, from the signal from the rotary encoder 21, it is possible to obtain the feed amount of the coil spring 11 based on the movement distance of the coil spring 11 per one rotation of the guide blade 18 previously obtained.

The winding diameter of the coil spring 11 varies depending on the accommodation amount of the coil spring 11 in the rotary drum 13, that is, for example, whether the coil spring 11 is wound around the small drum 17 in single or double. The moving distance of the coil spring 11 per one rotation of the blade 18 changes. In addition, when the coil spring 11 is fed, the winding diameter of the coil spring 11 is reduced (wraps around the small drum 17), and when it is returned, the coil spring 11 tends to expand (pressed against the inner wall side of the cylindrical portion of the rotary drum 13). Therefore, the count value may be incorrect. So, (1) prepare two kinds of converted values for sending and returning, or (2) prepare a total of four kinds of converted values for single winding and double winding for each feed and return, (3) The present sending amount can be stored and the conversion value can be changed continuously.

Now, the diameter of the outer rotating drum 13 is 300 m.
m, the diameter of the small drum 17 is 220 mm, the outer diameter of the coil spring 11 is 14 mm, and an example in which the rotary encoder 21 which outputs 500 pulses per rotation is used will be described. When the moving distance of the coil spring 11 when the guide blade 18 makes one rotation is measured, it was 80.5 cm 2. At this time, since the rotary encoder 21 also makes one revolution, 50
0 pulses are output. Therefore, 80.5 / 500 =
From 0.161, the relationship of (number of output pulses) * 0.161 = (moving distance of coil spring 11) (cm) holds. This numerical value of 0.161 is a converted value.

The amount of movement of the coil spring 11 is as follows.
At about 3.5 m, the winding changes from double winding to single winding in the rotary drum 13 and the winding diameter changes, so that the moving distance of the coil spring 11 when the guide blade 18 makes one rotation also changes. . The same occurs when the coil spring 11 is fed and returned. In this case, if another conversion value prepared in advance is used, an accurate distance can be obtained.

[0013]

As described above, according to the present invention, (1) the rotation detector takes up little space because it is installed in the small drum. (2) Since only a rotation detector needs to be newly added, it is simple. (3) Since the slip does not occur unlike the method in which the coil spring is sandwiched between the rollers, accurate distance display is possible if pulse conversion is optimally performed.

[0014]

[Brief description of the drawings]

FIG. 1 is an overall side view of a cable accommodating device constituting a rotary in-pipe camera according to the present invention.

FIG. 2 is a schematic structural explanatory view of a rotary drum in the cable housing device shown in FIG.

FIG. 3 is a schematic exploded perspective view showing an assembling configuration of a rotary drum, a small drum, and a guide blade shown in FIG. 2;

FIG. 4 is a schematic cross-sectional view of a main part, showing a mounting structure of a guide blade and a rotation detector shown in FIG. 3;

FIG. 5 is a schematic perspective explanatory view showing a mounting structure of the rotary drum shown in FIG. 2 with a transmission gear mechanism, and a wiring structure of a signal line in a rotation detector.

FIG. 6 is a schematic structural explanatory view showing an example of a rotating drum constituting a current rotary in-pipe camera.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Cable accommodating device 11 Coil spring 12 Base 13 Rotary drum 14 Motor 15 Transmission gear mechanism 16 Manual operation handle 17 Small drum 18 Guide vane 19 Unfold prevention vane 20 Guide frame 21 Rotary encoder 22 Bearing 23 Rotation axis 24 Signal line 25 Projection 26 Disk 27 Drum gear 28, 29 Connector 30 Slip ring 31, 32 Conducting wire 33 Holding spring

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G01B 5/00-5/30 G01B 21/00-21/32 F16L 55/00 G02B 23/24-23 / 26

Claims (5)

(57) [Claims] 1. A coil spring containing a long cable provided with a camera unit for capturing an image of a damaged portion in a pipe at a distal end is fed into the pipe while being taken up from the pipe.
Has a rotating drum for volume, inside the rotating drum, by rotating the rotating drum, provided with a small drum for winding the coil spring, the coil of the small drum
A rotating drum and small
Guides the coil spring, which rotates independently of the drum
Rotary tube cameras that the guide means provided with, characterized in that a structure with rotation detector to operate following the rotation of the guide means. 2. In the rotary in-pipe camera, when the coil spring is pulled out of the small drum via the guide means to the outside of the rotary drum or wound around the small drum, the rotation amount of the rotating guide means is detected. A cable length measuring method in a rotary in-pipe camera, wherein a movement amount of the coil spring is obtained from a detection signal concerning the rotation amount. 3. A coil spring, which derives a moving distance of the coil spring from a detection signal relating to a rotation amount of the guide means, applies a specific conversion value when sending out the coil spring, and applies a unique conversion value when winding the coil spring. A cable length measuring method for a rotary in-pipe camera, wherein a moving distance of the cable is obtained. 4. A method according to claim 1, further comprising: determining a moving distance of the coil spring from a detection signal relating to a rotation amount of the guide means; A method for measuring a cable length in a rotary in-pipe camera, wherein a converted value is applied to determine a moving distance of a coil spring. 5. When deriving a moving distance of a coil spring from a detection signal relating to a rotation amount of a guide means, a current feeding amount is stored, and a converted value is continuously changed and applied.
A cable length measuring method in a rotary inner tube camera, wherein a moving distance of a coil spring is obtained.