JPH0732527B2 - Cable laying equipment - Google Patents

Description

Description: [Industrial field of application] The present invention relates to a cable laying device for laying, for example, an electric power cable in an underground conduit.

[Prior Art] Conventionally, as a means for laying an electric power cable in the ground, manholes are provided at both ends of a place to be laid, a pipe line is buried between both manholes, and the manhole is wound around a cable drum on the ground. Connect the wire of the required length to the tip of the power cable, send the tip of the wire from one manhole to the other manhole through the pipeline, and guide the wire sent to the manhole to the ground via the gold wheel,
In addition, a method is known in which a winch on the ground is used to pull the power cable through the underground conduit.

Then, in this installation, in order to prevent an unreasonable force from being applied to the power cable, a tension meter is connected to the gold wheel and the tension applied to the power cable is monitored.

However, the tension measured via the gold wheel is the total force of the tension applied to the power cable and the tension of the wire, and it was not possible to directly measure only the tension applied to the power cable.

In addition, the pipeline is often buried right under the road, so the pipeline has not only bends and slopes, but also a step at the joint, and the power cable is squeezed at these points when the power cable is pulled. A phenomenon, that is, lateral pressure occurs.

Although the condition of these pipelines can be confirmed to some extent by inspection work such as numerical calculation based on the drawings at the time of construction and inspection of the bobbin through before laying the cable, the details of the condition and the sudden occurrence of damage to the cable The current situation is to rely on the intuition of a skilled person to detect such abnormal phenomena.

[Problems to be Solved by the Invention] As described above, in the conventional laying method, the tension applied to the power cable cannot be directly measured, and the lateral pressure generated at the bent portion of the pipeline is also applied. In many cases, excessive force is applied, making safe, reliable, and efficient installation difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to easily and accurately monitor tension and lateral pressure applied to a cable, thereby providing safe, reliable, and efficient installation. It is to provide a cable laying device capable of performing the above-mentioned work and significantly improving the quality of laying work.

[Means for Solving the Problems] In a cable laying device for laying a cable by pulling it with a wire through an underground pipe, the tension applied to the cable is detected as a continuous change amount. And a plurality of side pressure detecting means attached to the cable and arranged along the circumferential direction of the cable to detect the same side pressure applied to the cable as a continuous change amount, and the tension detecting means. And a transmitting means for transmitting the detection result of each of the side pressure detecting means to the outside of the pipeline, and a receiving means provided outside the pipeline for receiving the transmission signal of the transmitting means.

[Operation] When the cable is pulled by a wire and inserted into the underground pipeline, tension and lateral pressure are applied to the cable. At this time,
The tension detecting means detects the tension applied to the cable as a continuous change amount. Furthermore, the same lateral pressure applied to the cable is detected as a continuous change amount by a plurality of lateral pressure detecting means arranged along the circumferential direction of the cable. The detection results of the tension detecting means and the side pressure detecting means are transmitted outside the pipeline by the transmitting means, and the transmission signal is received by the receiving means outside the pipeline.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, 1 and 2 are manholes, both ends of the place where you want to lay the power cable (distance of several hundred meters).
It is provided in. A pipe line 3 is buried from the bottom of the manhole 1 to the bottom of the manhole 2.

A cable drum 4 is installed near the opening of the manhole 1 on the ground. This cable drum 4
A power cable 5 is wound around the power cable 5, and the power cable 5 is sequentially fed into the manhole 1 by an electric caterpillar 6.

Inside the manhole 1, a plurality of pipe rollers 7 for guiding the power cable 5 to the conduit 3 are provided.

A transmission unit 10 is connected to the tip of the power cable 5 via a pooling eye 8 and a return device 9, and a tension / side pressure gauge as a detection means is provided at the end of the transmission unit 10.
11 is installed. Then, a wire rope 12 for pulling is connected to the tip of the tension / side pressure gauge 11, and the tip of the wire rope 12 is fed into the conduit 3 and enters the inside of the manhole 2.

The transmission unit 10 has an outer diameter smaller than the inner diameter (130 mm to 150 mm) of the pipeline 3 so that the transmission unit 10 can be inserted through the pipeline 3 together with the tension / side pressure gauge 11. It has enough strength to withstand even.

The wire rope 12 is a so-called wire rope with an electric wire in which a three-core electric wire for signal transmission is built, and has a sufficient strength to endure repeated use. The electric wire of the wire rope 12 has the tension
Transmitting unit by the signal line passing through the cover of the lateral pressure gauge 11.
It is electrically connected to 10, and together with the signal line and the transmission unit 10, constitutes a transmission means for transmitting a detection signal of the tension / side pressure gauge 11 to a reception unit 17 described later.

A gold wheel 13 is provided inside the manhole 2, and the gold wheel 13
Thus, the wire rope 12 coming out of the pipe line 3 is guided to the opening side of the manhole 2.

On the other hand, on the ground, a guide roller 14, an electric winch 15, a wire winding drum 16, and a receiving unit 17 are installed near the opening of the manhole 2.

The guide roller 14 guides the wire rope 12 to the electric winch 15.

The electric winch 15 pulls in the wire rope 12 and winds it around the wire winding drum 16.

The receiving unit 17 is electrically connected to an electric wire of the wire rope 12 through a slip ring (not shown) attached to the wire winding drum 16, and a signal, that is, tension / side, sent through the electric wire. The detection signal of the pressure gauge 11 is received.

Here, a specific configuration of the tension / side pressure gauge 11 is shown in FIG.

That is, the tension / side pressure gauge 11 comprises a tension rod strain gauge 22 which is a tension detecting means and a side pressure strain gauge which is a side pressure detecting means on a round bar (a small diameter portion where strain can be easily captured) 21.
23, the tension (tensile strain) F ₁ applied to the power cable 5 is detected by the tension strain gauge 22, and the same side pressure (bending strain) F ₂ applied to the power cable 5 is detected as the side pressure strain gauge 23.
Detect with.

In addition, it is possible to cope with the rotation of the round bar 21 due to the action of the return device 9, and to which position on the circumferential surface of the round bar 21 the lateral pressure (bending strain) is applied.
In response to the fact that F ₂ is added or cannot be specified, the lateral pressure strain gauge 23, which is the lateral pressure detecting means, actually has a plurality of four, for example, 23a, 23b, 23c, and 23d, which are the circumferential direction of the round bar 21. (That is, along the circumferential direction of the power cable 5) at equal intervals.

On the other hand, FIG. 3 shows a configuration of an electric circuit of a main part including the tension / side pressure gauge 11.

First, the tension strain gauge (tension detecting means) 22 of the tension / side pressure gauge 11 is composed of a bridge circuit of four elements, and detects the tension applied to the power cable 5 as a continuous change amount. Side pressure strain gauge of tension / side pressure gauge 11 (tension detection means)
Each of 23a, 23b, 23c, and 23d is composed of a bridge circuit of four elements, and detects the same lateral pressure applied to the power cable 5 as a continuous change amount. These tension strain gauges 22
The transmitters 31, 32a, 32b, 32c, 32d of the transmitter unit 10 are connected to the and side pressure strain gauges 23a, 23b, 23c, 23d, respectively.

The transmitters 31, 32a, 32b, 32c, 32d are connected to the receiving unit 17 via the wire 12a of the wire rope 12.

The oscillators 31, 32a, 32b, 32c, 32d use the power supply unit 33 as an operating power source, and start up by receiving a calling signal of a specific frequency from the receiving unit 17, and emit an electric signal according to the state of the strain gauge. It is a thing. The frequency of the calling signal is different for each transmitter.

The receiving unit 17 comprises a calling device 41 and a CPU (central processing unit) 42.

The calling device 41 transmits a calling signal to each of the transmitters of the transmitting unit 10 in a predetermined order, and takes in a signal emitted from each transmitter in response to the transmission.

The CPU 42 detects the tension applied to the electric power cable 5 based on the signal of the tension strain gauge 22 of the signal taken in by the calling device 41, and the side pressure strain gauge 23a of the signal taken in by the calling device 41. A functional means for detecting the lateral pressure applied to the power cable 5 based on the signals of 23b, 23c, and 23d, and a functional means for judging whether or not the detected tension and lateral pressure meet a predetermined allowable condition, And functional means for controlling the operation of the electric winch 15 according to the result of the determination.

Next, the operation of the above configuration will be described.

The tip of the wire rope 12 is inserted from the manhole 1 into the conduit 3 and led out to the opening of the manhole 2 via the gold wheel 13. Then, the tip end of the wire rope 12 is connected to the wire winding drum 16 via the guide roller 14 and the electric winch 15.
At this time, the wire 12a of the wire rope 12 is electrically connected to the receiving unit 17 via a slip ring (not shown) attached to the wire winding drum 16.

When the electric winch 15 is started in this state, the wire rope
12 is pulled in the direction of the arrow shown in FIG.

The electric power cable 5 wound around the cable drum 4 is sequentially fed into the manhole 1 by the pulling by the wire rope 12 and the feeding of the electric caterpillar 6.

The fed electric power cable 5 is inserted into the pipe line 3 while being guided by the pipe roller 7 by further pulling.

At the time of this insertion, the tension applied to the power cable 5 is detected by the tension strain gauge 22 of the tension / side pressure gauge 11 as a continuous change amount. In addition, the same lateral pressure applied to the power cable 5 by the bent portion or the step of the pipeline 3 is the tension / side pressure gauge 11
Any of the lateral pressure strain gauges 23a, 23b, 23c, and 23d at 7 is detected as a continuous change amount.

The detection result of the tension / side pressure gauge 11 is transmitted to the reception unit 17 by the transmission unit 10 and the wire 12a of the wire rope 12.

The receiving unit 17 detects the tension and the lateral pressure applied to the power cable 5 from the received signal, and if the detection result meets a predetermined allowable condition, the operation of the electric winch 15 and the operation of the electric caterpillar 6 are continued. .

However, if the detection result does not match the predetermined allowable condition, the receiving unit 17 determines that there is an abnormality and stops the operation of the electric winch 15 and the operation of the electric caterpillar 6. By this stop, it is possible to prevent the occurrence of defects such as external damage, deformation, and deterioration of electric performance of the power cable 5.

In this case, the worker may be notified of the abnormality by ringing a buzzer or lighting a lamp.

In this way, the tension / side pressure gauge 11 provided on the power cable 5 detects the tension and side pressure applied to the power cable 5 directly and as a continuous change amount, and the detection result is transmitted to the transmission unit 11 and the wire rope 12 Since the signal is transmitted to the receiving unit 17 on the ground, the process of changes in tension and lateral pressure applied to the power cable 5 can be easily and accurately monitored. Moreover, a plurality of lateral pressure strain gauges 23a, 23b, 23 are arranged along the circumferential direction of the power cable 5.
Since c and 23d are arranged, lateral pressure can be accurately captured at any position in the circumferential direction.

Therefore, safe, reliable, and efficient laying can be performed, and the quality of laying work can be significantly improved.

In addition, the CPU 42 of the receiving unit 17 can manage the installed cables individually by accumulating various data obtained at the time of installation, and of course, prior examination and data for cable installation on the same route at a later date. A great effect can be expected for analysis.

In addition, in the said Example, although the case where a power cable was laid was demonstrated, it is not restricted to it, but it can be applied to various cables, such as laying of a communication cable.

Besides, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

[Effects of the Invention] As described above, according to the present invention, the tension detecting means detects the tension applied to the cable as a continuous change amount, and a plurality of side pressure detecting means arranged along the circumferential direction of the cable. According to the configuration, the same lateral pressure applied to the cable is detected as a continuous change amount, these detection results are transmitted to the outside of the pipeline by the transmitting means, and the transmission signal is received by the receiving means outside the pipeline. As a result, the process of changes in tension and lateral pressure applied to the cable can be monitored easily and accurately, which enables safe, reliable, and efficient laying, and greatly improves the quality of laying work. It is possible to provide a possible cable laying device.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, FIG. 2 is a perspective view showing a specific configuration of a tension / side pressure gauge in the embodiment, and FIG. 3 is a main part of the embodiment. It is a block diagram of an electric circuit. 1,2 …… Manhole, 3 …… Pipeline, 5 …… Power cable, 10 …… Transmitting unit (transmitting means), 11 …… Tension / side pressure gauge (detecting means), 12 …… Wire rope, 12a …… Electric power (transmitting means), 15 ... electric winch, 17 ... receiving unit.

Claims (1)

[Claims] 1. A cable laying device for laying a cable by inserting it into an underground pipe line by pulling with a wire, the tension detecting means being attached to the cable and detecting the tension applied to the cable as a continuous change amount. A plurality of side pressure detection means attached to the cable and arranged along the circumferential direction of the cable to detect the same side pressure applied to the cable as a continuous change amount; and the tension detection means and each side pressure. Cable laying, comprising: transmitting means for transmitting the detection result of the detecting means to the outside of the pipeline, and receiving means provided outside the pipeline for receiving the transmission signal of the transmitting means. apparatus.