JPH0110816Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an optical fiber-containing cabtire cable for transportation, which has optical fibers in the twisted conductor. The purpose of this invention is to protect the optical fiber and relieve stress on the optical fiber when the cable is used.

To operate industrial mobile machines such as stacker cranes and claimers, it is necessary to have a power supply cable to the mobile machine as well as a signal transmission cable for control or image transmission between the mobile machine and the remote control room. These cables have a rectangular cross section because they are used by being wound around reels attached to moving machines, and are generally called flat electric cables for moving.

By the way, the signal transmission cable is used by being wound on a separate reel at a certain distance from the power supply cable in order to avoid induction interference from the power supply cable.

However, in recent years, optical cables have developed, and since these cables are completely free from inductive interference, research is underway to install them in parallel with power cables, or to combine them with them, and some of them have even been put into practical use. .

Similarly, research is underway to incorporate optical cables into mobile flat electric cables, but this has not yet been put to practical use. This is because when the rubber or plastic sheath that collectively covers the electric cable and the optical cable is vulcanized or crosslinked, the optical fiber is significantly adversely affected by the heat generated. In other words, optical fiber is made of silica glass fiber, which is extremely weak compared to copper wire, which is an electrical conductor, and is coated with silica glass fiber to strengthen it. The silicone resin coating and the nylon resin coating on the outside undergo thermal deformation due to the heat generated during vulcanization or crosslinking of the rubber/plastic sheath, and this deformation causes minute deformation of the silica glass fiber. This is because, as a result, so-called microbend loss and the like occur, deteriorating the optical fiber characteristics.

In addition, since moving cables are always used with bending deformation, if an optical fiber is built into the cable, stress such as lateral pressure is applied to the optical fiber, causing minute deformation of the silica glass fiber. If this cannot be sufficiently prevented, optical transmission loss will increase, and this is also one of the reasons why the practical application of optical fiber-containing flat electric cables has been delayed.

The present invention has been developed as a result of intensive research in view of the current situation and has solved the above-mentioned drawbacks. That is,
The present invention is an optical fiber-containing cab tire cable for transportation using a twisted conductor with a built-in optical fiber bar code. This is an optical fiber-containing cab tire cable for transportation, which is characterized by using an optical fiber bar code having sequentially the following.

Next, the present invention will be explained using the drawings.

FIG. 1 shows a cross-sectional view of an ethylene-propylene rubber insulated chloroprene skid tire cable 1 containing optical fibers, which is an embodiment of the present invention.

In Figure 1, 2 is an optical fiber barcode, 3
is a conductor strand consisting of 16 annealed copper wires with an outer diameter of 0.45 mm, 4
is an insulating layer made of ethylene-propylene rubber,
Reference numeral 5 designates an inner sheath made of chloroprene rubber, 6 a reinforcing layer made of canvas, and 7 an outer sheath made of chloroprene rubber, in which conductor wires 3 are arranged around an optical fiber bar cord 2 with an outer diameter of 2.5 mm. 18 strands twisted in 2 layers, on top of which 4 insulator layers,
An inner sheath 5 and a canvas reinforcing layer 6 are sequentially applied to form a power cable 8 with a built-in fiber optic bar code.Three of these cables 8 are arranged in parallel and an outer sheath 7 is applied on the outside to form a mobile cable containing optical fiber according to the present invention. It is made of Yabutire cable.

FIG. 2 shows an enlarged cross-section of the optical fiber barcode 2 in FIG. 1. That is, the optical fiber barcode 2 has a fluororesin coating layer 10 with a thickness of about 0.4 mm provided on the outside of an optical fiber 9 with a diameter of 125μ, a fibrous material reinforcing layer 11 made of Kevlar on top of that, and a fibrous material reinforcing layer 11 made of Kevlar on top of that. A stress buffering layer 12 made of ethylene propylene rubber is provided to form an optical fiber barcode with a finished diameter of 2.5 mm. In addition to EPR, various rubbers such as NR and IIR are suitable for the stress buffer layer.

For comparison, the optical fiber bar code 2 shown in FIG. 2 is the same except that a nylon resin coating layer with a thickness of about 0.4 mm is used instead of the fluorine resin coating layer 10 with a thickness of about 0.4 mm. Using this, an optical fiber-containing cab tire cable (comparative example) similar to that shown in FIG. 1 was produced.

Both cables were heated to 150°C during vulcanization.

Therefore, when we measured the attenuation of the optical fibers for both of the above-mentioned cables that were subjected to heat, the cable according to the present invention had an attenuation of 2 to 3 db/Km, while the cable of the comparative example had an attenuation of 15 to 20 db/Km. It was found that the cable of the present invention, which uses an optical fiber cord coated with a fluororesin coating layer, has significantly less attenuation and extremely less microbend loss due to heat than the comparative example.

Further, by providing the stress buffering layer, the optical fiber has the role of protecting the optical fiber from stress during twisting with conductor wires and further from stress due to bending during actual use of the cable. It is preferable to place the fiber optic barcode in the center of the stranded conductor because this minimizes bending stress.

In the embodiment shown in FIG. 1, a desired number of conductor strands 3 are twisted around the optical fiber barcode 2, but a plurality of conductor strands 3 constituting the conductor Bundle the annealed copper wires to form a conductor strand containing an optical fiber bar code, and twist the desired number of conductor strands made only of annealed copper wire around this special conductor strand as the center, as shown in Figure 1, and place on top of it. The insulating layer 4, the inner sheath 5, and the canvas reinforcing layer 6 may be sequentially applied to form the power cable 8 with a built-in optical fiber bar code. In other words, it is also possible to construct a conductor made by twisting a desired number of conductor strands, in which the optical fiber bar code 2 shown in FIG. 2 is incorporated only in the central conductor strand.

As described above, the optical fiber-containing cab tire cable of the present invention has a fluorine resin coating layer on the outside of the optical fiber, so it is not affected by heat even if exposed to high temperatures during vulcanization, crosslinking, etc. , does not cause microbend loss, and has a stress buffering layer on the outside of the optical fiber, which relieves stress on the optical fiber during twisting of the optical fiber cord and conductor strands and during actual use of the cable, making it suitable for transportation. This is an extremely excellent cab tire cable.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an optical fiber-containing cabtire cable according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of the optical fiber bar code in FIG. 1. DESCRIPTION OF SYMBOLS 1... Cab tire cable with optical fiber, 2... Optical fiber bar code, 3... Conductor strand, 4... Insulator layer, 5... Inner layer sheath, 6...
Reinforcement layer, 7... Outer layer sheath, 8... Power cable with optical fiber bar code, 9... Optical fiber,
10... Fluorine resin coating layer, 11... Fibrous material reinforcing layer, 12... Stress buffer layer.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In an optical fiber-containing cab tire cable for transportation using a twisted conductor with a built-in optical fiber barcode, as the optical fiber barcode, a fluororesin coating layer on the optical fiber, a fiber 1. An optical fiber-containing cab tire cable for transportation, characterized in that it uses an optical fiber bar code having a material reinforcing layer and a stress buffering layer sequentially. (2) The optical fiber-containing cab tire cable for transportation according to claim 1, characterized in that the twisted conductor is a twisted conductor having an optical fiber bar code built into the center of the twisted conductor. (3) The optical fiber-containing cabtire cable for transportation according to claim 1 or 2, wherein the stress buffering layer is made of rubber.