JP2948411B2 - Self-propelled inspection method and equipment in piping - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-propelled inspection system in a pipe capable of remotely inspecting the inside of a pipe such as a gas pipe or a water pipe buried underground from the ground, and the like. The present invention relates to a method and an apparatus for detecting a stop state due to the above.

[0002]

2. Description of the Related Art Conventionally, there is known a self-propelled inspection system in a pipe for inspecting a pipe such as a gas pipe or a water pipe buried underground for scratches, pits, cracks and the like inside the pipe. As shown in FIG. 3, the probe 1 comprises a probe 1 which runs in a pipe by itself and a control device on the ground (not shown) connected by a cable 12, and the probe 1 comprises a camera unit 2, a camera It has a head joint 10, a drive vehicle unit 3, a geared motor 4, and a cable joint 11, which are connected by a flexible joint 7. Camera unit 2
A television camera is built in the inside, and images of scratches, pits, cracks, etc. in the piping are taken and displayed on a CRT in a control device on the ground. The driving vehicle unit 3 has three wheels arranged radially and is elastically pressed against the inner wall of the pipe during traveling, and is driven to rotate by the geared motor 4 via the flexible shaft 7, whereby the probe 1 moves forward. , Retreat.

[0003]

However, burrs or steps at the pipe end of the pipe connecting portion 26 in the pipe 25, or bends, tips of spigot fixing bolts, etc., impede the travel of the probe 1 in the pipe. There are various obstacles,
Is hindered with considerable frequency. Conventionally, when such a running obstacle occurs, a person searches for the state of the running obstacle in the pipe with a television camera at the tip, and reduces the diameter of the three wheels of the driving vehicle unit 3 to pass the running obstacle. I was letting it.
For this reason, the operator must constantly watch the image of the television camera, which requires a great deal of labor and requires a skillful handling in order to smoothly pass the obstacle. Further, if the driver does not notice the stop of the probe 1 due to an obstacle, an excessive load is applied to the geared motor 4 and the motor may be burnt or the wheels may be damaged.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention has a drive vehicle unit driven by a motor, and searches for a pipe shape of a buried pipe by a probe capable of self-propelling in the pipe. In the method for self-propelled inspection in a pipe, the drive vehicle unit is reduced in diameter when it is determined that the probe is in a stopped state by measuring an increase in load current of a motor of the probe. It is. The present invention also provides a self-propelled inspection device in a pipe for exploring a pipe shape of a buried pipe by a probe capable of self-propelling in a pipe, wherein the probe self-propelled by a driving vehicle unit driven by a motor in the pipe. A load current measuring unit installed on the ground for measuring the load current of the motor of the probe, and a cable connecting the probe and the load current measuring unit, wherein the load current measuring unit includes a load current of the motor. A signal for reducing the diameter of the driving vehicle unit is detected when an increase in the vehicle speed is detected. Further, the probe has a camera unit, a driving wheel unit, and a geared motor unit, each unit is flexibly connected, and the driving wheel unit is elastically pressed against the inner wall of the pipe, and the center of the pipe is It is characterized by having a traveling wheel whose diameter can be reduced in the direction.

[0005]

According to the present invention, since the probe has the above-described structure, the probe which travels in the pipe can be formed with a burr or a step at the pipe end of the pipe connection portion 26 in the pipe 25, or a bend portion or a tip of a spigot fixing bolt. When the travel of the probe 1 is hindered, the travel inhibition of the probe 1 can be immediately detected by measuring the increase in the load current. Furthermore, since the driver unit 3 is reduced in diameter immediately after the measurement of the increase in the load current, the driver unit 3 can automatically pass through the obstacle.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing one embodiment of the present invention. The probe 1 has a camera head unit 2 having a TV camera built in front thereof, and a camera head joint 10, a triple drive vehicle unit 3, a double geared motor unit 4, and another It consists of three drive vehicle units 3 and a cable joint 11, which are connected by flexible joints 6, 7 which can be freely bent.

[0007] The flexible joint 6 between the camera head unit 2 and the driving vehicle unit 3 is formed of a bendable hollow tube such as a metal spiral tube, and contains wiring leading to the camera head unit 2. The flexible joint 7 between the drive vehicle unit 3 and the geared motor unit 4 has a metal spiral tube and a flexible coil spring or a universal joint for connecting the geared motor unit 4 and the drive vehicle unit 3. Contains drive shaft. The two geared motor units 4 drive the drive vehicle unit 3 directly connected to each other, and rotate the wheels pressed against the inner wall of the drive vehicle unit 3 to move forward and backward. Driving car unit 3
Has three wheels radially projecting outward, and these wheels are pressed toward the inner wall of the pipe by an elastic means such as a cylinder or a spring by air pressure, and can be reduced in diameter toward the center by air pressure.

The cable joint 11 has a cable 12
Are connected to a controller 16 via a cable drum 15 on the ground. The cable 12 is a composite cable including a power line for the geared motor unit 4, a signal line for the camera head unit 2, and an air tube for a wheel pressing cylinder.

The controller 16 is further connected to a compressor 17 for supplying air pressure, a personal computer 20, and a power supply 18. The controller 16 includes a regulator for supplying a predetermined air pressure for wheel pressing to the driving vehicle unit 3, a constant voltage circuit for supplying a constant voltage sufficient for driving the geared motor, and an ammeter for measuring a load current of the geared motor. It has a recorder to record the load current. Further, the controller 16 is connected to a CRT for displaying an image of the camera unit 2 for displaying an image in the pipe. Further, a personal computer 29 is connected to the controller 16 to determine whether the measured value of the ammeter for measuring the load current is a normal value or an abnormal value.
When the value is an abnormal value, a signal is sent to the controller 16 to reduce the air pressure for wheel pressing to reduce the diameter of the drive vehicle unit 3.

[0010] Explaining the self-propelled inspection of the pipe in this embodiment, the probe 1 inserted in the pipe 25 advances in the pipe by the operation of the driving vehicle unit 3. There are horizontal and vertical pipes, pipe ends that interfere with travel, pipe connections with spigot fixing bolts, bends, etc., but horizontal sections run relatively smoothly and run vertically. The running resistance differs depending on the own weight of the probe 1 for the undesired portions, and unique vibrations are generated in the probe 1 when the pipe connection portion and the bend portion can run, respectively. Therefore, when the load current of the geared motor 4 is measured, it is possible to know the position of the probe 1 traveling in the pipe.

When the probe 1 is caught and stopped at the pipe connection portion or the bend portion, a large current flows through the geared motor 4 due to the stop of the motor or an excessive load. FIG.
Is a graph in which the running resistance at various positions of the probe 1 is measured and recorded by experiment, the horizontal axis of which is the amount of movement of the probe 1 and the vertical axis is the amount of load current. FIG. 2A shows the load current when traveling in a horizontal and straight pipe, which is about 0.7 amperes. (B) is a load current when traveling on a bend portion that is bent and rises in a vertical plane. Shows a state in which a vibration waveform is generated while increasing, and the load current changes to about 1.1 amperes after entering the rising portion. It should be noted that although not shown, the load current is about 0.3 amperes when descending the riser.

FIG. 2 (c) is a graph when the probe 1 is stopped by being caught. It can be seen that the load current is remarkably increased to about 4.5 amps in the stopped state. Therefore, it can be easily determined that the probe 1 is stuck. Further, at this time, the value of the load current is compared with the current value for normal running stored in the personal computer 20 or an appropriate storage means,
If the load current is larger, the air pressure regulator in the controller 16 is controlled to reduce the cylinder that presses the wheels of the drive vehicle unit 3 of the probe 1 to reduce the drive vehicle unit 3.
Is reduced in diameter. At this time, the rotation drive of the traveling wheels by the geared motor unit 4 is temporarily stopped, but need not be stopped. Therefore, the probe 1 can proceed automatically and promptly out of the hooked state.

[0013]

As described above, the probe 1 has a pipe connection portion having a pipe end or a spigot fixing bolt which hinders traveling,
When it is caught by a bend or the like, only the load current of the geared motor 4 for traveling of the probe 1 is measured,
The hooking can be easily detected. Also,
By reducing the diameter of the drive vehicle unit 3, it is possible to automatically remove the hook and proceed. Therefore, labor is reduced in performing the self-propelled inspection in the pipe, and quick construction can be performed.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a pipe self-propelled inspection device of the present invention.

FIGS. 2 (a) to 2 (c) are graphs showing load currents when the probe travels or when a fault occurs.

FIG. 3 is an explanatory view of a conventional in-pipe self-propelled inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Explorer 3 Drive vehicle unit 4 Geared motor unit 6, 7 Flexible joint 16 Controller

Claims (3)

(57) [Claims] 1. A method for self-propelled inspection in a pipe having a drive vehicle unit driven by a motor and using a probe capable of self-propelling in the pipe to detect a pipe shape of a buried pipe. A method for self-propelled inspection in a pipe, wherein the drive vehicle unit is reduced in diameter when it is determined that the probe is in a stopped state by measuring an increase in current. 2. A self-propelled inspection device in a pipe for exploring a pipe shape of a buried pipe by a probe capable of self-propelling in the pipe,
A probe which is driven by a driving vehicle unit driven by a motor in the pipe, a load current measuring means installed on the ground for measuring a load current of the motor of the probe, the probe and the load current measuring means, Wherein the load current measuring means generates a signal for reducing the diameter of the drive vehicle unit when detecting an increase in the load current of the motor. 3. The searcher has a camera unit, a driving wheel unit, and a geared motor unit, each unit is flexibly connected, and the driving wheel unit is elastically pressed against the inner wall of the pipe. The self-propelled inspection device in a pipe according to claim 2, further comprising a traveling wheel capable of reducing a diameter in a direction toward a center of the pipe.