JPH0295111A - Cable laying method and device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a cable unwinding method that enables efficient cable laying with good workability in a cable laying method in which a cable is conveyed in a pipe by a flow of compressed air. The present invention also relates to a cable unwinding device that is used directly to carry out the cable unwinding method.

[Conventional technology]

As an example of a conventional cable feeding device used in a cable laying method in which the cable is conveyed in the downstream direction of the compressed air flow inside the pipe by the flow of compressed air flowing into the pipe, for example, the cable feeding device whose configuration is shown in Fig. 2 is an example. Known (IEEF.

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August (1986) pp679).

1 is a cable, 21 is a cable supply bobbin, 22 is a cable insertion port, 23 is a capstan roller, 28 is a compressed air inlet, and 29 is a tube for conveying and installing the cable 1. In this cable feeding device, a cable supply bobbin 21 is arranged outside the cable feeding device, and a capstan roller 23 built in and installed in the cable feeding device takes in the cable 1 from a cable insertion port 22, and compressed air flows into the cable feeding device. A mechanism is provided for feeding the cable 1 together with the compressed air flowing in from the inlet 28 into the pipe 29 carrying it.

[Problems to be Solved by the Invention] Conventional cable feeding devices have a structure in which the cable is inserted from the outside of the cable feeding device. Since a space is required in between, the compressed air that flows into the pipe that conveys the cable through the cable payout device blows out from this part. For this reason, when carrying out cable conveyance and installation using airflow over long distances, it is necessary to increase the pressure of the compressed air fed into the cable feeding device to increase the flow velocity of the airflow generated within the pipe. However, as mentioned above, due to the leakage of the inflowing air, sufficient cable conveying pressure cannot be obtained. In other words, it is difficult to completely seal air leaks when compressed air pressure is high, and it is extremely difficult to seal air leaks when transporting cables of different shapes or sizes. Have difficulty. In particular, when compressed air is obtained by a compressor, there is a limit to the discharge capacity of the compressor, so if there is an air leak, the maximum pressure that can be obtained will be reduced. For this reason, a large compressor with a large discharge capacity is required for long-distance cable feeding using airflow, which poses a problem in that it is disadvantageous in terms of workability in transportation and installation work of equipment, and in terms of equipment cost.

The present invention solves the conventional problems and provides a method and a device for letting out a cable, which enables efficient laying with good workability in a cable laying method in which the cable is conveyed in a pipe by a flow of compressed air. The purpose is to

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a cable laying and feeding method according to the present invention, in which a cable is housed in an airtight container having a compressed air inlet and a cable feeding port, and the cable is connected from the cable feeding port to the cable feeding port. It is characterized in that it is pumped into the cable conveyance pipe along with compressed air that flows into the airtight container from the compressed air inlet.

Furthermore, the cable laying and unwinding device directly used for carrying out the cable laying and unwinding method of the present invention has a central cylinder in which the cable is arranged in a winding manner, and an outer cylinder in which the cable arranged in a winding manner is housed between the central cylinder and the central cylinder. It has a built-in double cylindrical container, a guide ring that guides the end of the stored cable in the payout direction, and a guide roller that guides the cable led out through the guide ring in the payout direction,
A compressed air inlet on one side of the side wall, a cable outlet connected to the end of the pipe from which the cable is fed out and equipped with a capstan roller for cable feeding on the other side of the side wall, and a lid for sealing the cable. It is characterized by being constituted by an airtight container equipped with.

[For production]

The present invention is advantageous in that the outlet of the compressed air that flows into the payout fitting to create an air flow in the pipe carrying the cable does not exist anywhere else in the pipe carrying the cable joined to the cable payout opening. There is no leakage, the amount of compressed air flowing in is the minimum necessary, and when compressed air is obtained from a compressor or cylinder, a small one is better, and it is easier to work with.
It is advantageous in terms of equipment price.

In addition, when carrying out long-distance cable conveyance installation, it is necessary to increase the air pressure sent to the feeding attachment to increase the air flow velocity in the pipe and increase the cable carrying force due to the friction between the cable surface and the air. Equipment can respond by increasing air pressure from a compressor or cylinder. In the structure of conventional cable feeding devices, when the air pressure is increased, air leaks from the cable insertion port where the cable is inserted and supplied from the cable supply to the feeding device, and the amount of compressed air discharged from the compressor or cylinder increases. However, according to the present invention, this drawback can be solved.

In addition, when the next cable installation is to be carried out after a series of cables have been laid, open the lid of the airtight container constituting the feeding device of the present invention and insert the double cylindrical container that houses the built-in cable into the necessary cables. It is easy to operate, just replace the cable with one that is stored.

Examples will be described below based on the drawings.

〔Example〕

FIG. 1 is a schematic diagram of the configuration of an embodiment of the cable feeding device of the present invention. Reference numeral 1 designates a cable carried by an air flow, and reference numeral 2 designates a double cylindrical container in which the cable 1 is stored in a bundle in a wound state between a central cylinder and an external cylinder so that the cable 1 can be pulled out without becoming entangled.

The ends of the cables stored in a bundle are led out in the direction of payout via a guide ring, and guided in the direction of payout by guide rollers 4. The guided cable 1 is passed through a cable outlet 11 provided on one side wall of an airtight container 5 containing a double cylindrical container 2, a guide ring 7, and a guide roller 4, to the end of a tube 9 from which the cable is delivered. and is fed into the tube 9 by a capstan roller 3 mounted at the cable feed-out port 11. 8 is a compressed air inlet provided on the other side of the side wall of the airtight container 5, and 6 is a lid of the airtight container 5. The double cylindrical container 2 is taken in and out by opening the lid 6. M6 is fixed to the airtight container 5 with bolts 10.

The cable feeding device according to the present invention has a cable feeding port 10 in which the outlet of the compressed air sent into the airtight container 5 from the compressed air inlet 8 is joined to the pipe 9 for conveying the cable.
Only. With the cable feeding device of this structure, there is no leakage of the inflowing compressed air, and it is possible to efficiently carry and lay the cable over long distances using a small compressor.

An example in which a cable is fed out using the cable feeding device according to the present invention shown in FIG. 1 will be described below.

Straight PR tube 50 with inner diameter 6mmφ and outer diameter 8mmφ
For a length of 0m, the discharge amount is 80β/ as a compressed air supply source.
When using a compressor with a maximum pressure of 9.5 Kg/cm2, the air pressure inside the feeding device is 7.5 Kg/cm2 and the air flow rate at the outlet of the PE tube is 80β/min before the cable is conveyed. Ta.

On the other hand, in the cable feeding device of the conventional structure shown in FIG. 2, the air pressure inside the feeding device is 4.5 mm before the cable is conveyed for the same PE tube length of 500 m.
7Kg/cm" 1. The air flow rate at the PE tube outlet was 38β/min. In other words, out of the discharge rate of 801/min from the compressor that supplies compressed air, more than 401/min of air flowed through the cable insertion port 22. It is leaking from the part,
It was not possible to increase the compressor's air pressure or air flow rate any further.

Next, using the same compressor and the cable having the structure shown in FIG. 3, the cable is transported and laid by the cable feeding device according to the present invention shown in FIG. 1 and the cable feeding device having the conventional structure shown in FIG. An experiment was conducted. The cable used for the installation shown in Fig. 3 has an optical fiber core wire 31 covered with foamed polyethylene, and a jacket 3 with a diameter of 2 mmφ.
The cable has a structure subjected to 2 and has a weight of 2 g/m'.

In the cable feeding device according to the present invention shown in FIG.
Compressed air supply source discharge rate 801/min, maximum pressure 9.5K
With a compressor of g/c, m2, air pressure 9. 5
K g/c: PE tube straight line 150 Q in m2
It was possible to transport cables up to m length.

On the other hand, in the cable feeder of the conventional structure shown in Fig. 2, the same compressor is used, and the air pressure is 5.
．． Reduce to 8'g/cm2, PE tube straight 12 O
The limit of conveyance was up to Qm length.

This is because the cable feeding device of the conventional structure suffers from compressed air leakage, and since the compressor has a limit in the discharge amount, the air pressure cannot be sufficiently increased, and the cable carrying capacity is small.

The results of the above-mentioned cable payout and conveyance experiments also show that, according to the payout method using the cable payout device according to the present invention, high air pressure can be efficiently obtained with a compressor with a small discharge amount.

〔Effect of the invention〕

As explained above, when a cable is paid out by an air flow into a cable installation pipe, the present invention uses compressed air flowing into the drawing device to create an air flow in the pipe.
Since the cable is configured to be fed from the cable feeding port into the cable conveying pipe connected to the cable feeding port without leaking, high air pressure inside the cable feeding device can be obtained from above using a small compressor or compressed gas cylinder. In addition to improving the work efficiency of transporting and installing cable transport equipment to the installation site, it is possible to reduce equipment costs. Also, after completing a series of cable installations,
When performing the next cable installation, all you have to do is open the lid of the airtight container constituting the feeding device of the present invention and replace the built-in cable storage double cylindrical container with the required cable storage double cylindrical container. is easy. The present invention, which has the above-mentioned advantages, is a cable laying method in which a cable is conveyed and laid inside a pipe by generating an air flow in a pipe and applying a propulsion force by friction between the air and the cable conveyance.
The effect is great when applied to the market.

[Brief explanation of the drawing]

Fig. 1 shows the components of the cable feeding device of the present invention...compressed air inlet, 9.29...pipe, 10...bolt,
11... Cable feeding port, 21... Cable supply bobbin, 22... Cable insertion port, 31...
Optical fiber core wire, 32...Sheath (foamed polyethylene)
Patent applicant Sumitomo Electric Industries Co., Ltd. Agent Patent attorney Kugobe Ru Tamamushi.

Claims (2)

[Claims] (1) In a cable feeding method applied to a cable laying method in which the cable is conveyed in the downstream direction of the compressed air flow in the pipe by the flow of compressed air flowing into the pipe, the cable is connected to a compressed air inlet and a cable feeding port. The cable is housed in an airtight container having a cable outlet, and the cable is force-fed from the cable outlet into a cable conveying pipe connected to the cable outlet, together with compressed air flowing into the airtight container from the compressed air inlet. Cable laying and feeding method. (2) In a cable feeding device applied to a cable laying method in which the cable is conveyed in the downstream direction of the compressed air flow in the pipe by the flow of compressed air flowing into the pipe, the cable is arranged in a winding manner in a central cylinder; , a double cylindrical container made of an external cylinder that stores the cable arranged in a wound manner between the central cylinder and the central cylinder; a guide ring that leads out an end of the stored cable in a direction in which it is fed out; and the guide ring. It has a built-in guide roller that guides the cable led out through the cable in the unwinding direction, and a compressed air inlet on one side of the side wall, and a compressed air inlet on the other side of the side wall connected to the end of the pipe from which the cable is unrolled. A cable laying and feeding device comprising an airtight container including a cable feeding port equipped with a feeding capstan roller and a lid for sealingly storing the cable.