JPS6012724B2 - Manufacturing method of composite cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a composite cable containing optical fibers.

In recent years, composite cables in which optical fibers for information transmission are housed within electrical cables have been used.

However, in terms of strength and transmission characteristics, optical fibers are extremely sensitive to tension and the lateral pressure that occurs due to tension, so even if the composite cable is stretched by tension or thermal expansion, it is manufactured so that as little tension as possible is applied to the optical fiber. method needs to be adopted. Manufacturing methods in which optical fibers are simply twisted into cables do not allow for a large ratio of excess optical fiber length to the cable length, and if a large amount of cable elongates, a large amount of tension will be applied to the optical fibers. This will result in

An object of the present invention is to provide a method for manufacturing a composite cable in which no large tension is applied to the optical fiber even when the cable is stretched.

The gist of the present invention is to twist optical fibers around a core body to form or after forming an optical fiber strand, untwist it to a certain extent, or after untwisting it, store it in a pipe-shaped object, Thereafter, the optical fiber strand containing pipe-like object is assembled together with other cable elements.

Further, in order to prevent residual torsional stress in the optical fiber or the core, the optical fiber or the core may be twisted in advance before twisting the optical fiber around the core.

The configuration of the present invention will be specifically explained with reference to drawings showing embodiments. In FIG. 1, as a first step, an optical fiber 1 is wound around a core body 2.

Reference numeral 3 designates a core body 2, ie, a composite body, around which an optical fiber is wound; 4, a bobbin for sending out the core body; 5, a bobbin for sending out the optical fiber; and 6, a bobbin for the composite body.

At this time, the optical fiber feeding bobbin 5 may revolve around the core body 2 while rotating on its own axis.

As a second step, as shown in FIG.
When the composite body 3 is pulled out and stored in the pipe 7, the composite body bobbin 6 is rotated to untwist the composite body 3 and make it laugh. Such a pipe 7 is used as a third process.
As shown in the figure, a stranded composite cable is manufactured together with the electric wires 8.

FIG. 4 shows a modification of the first step, in which the optical fiber is wound around the core 2 and the composite bobbin 6 is rotated in the untwisting direction.

9 is a fixing device provided in the middle for fixing the optical fiber 1 and the core body 2 at appropriate intervals;
0 indicates a fixed part.

When the optical fibers 1 are twisted and untwisted at the same time, the composite is transferred to the pipe 7 in the second step.
If you store it inside, there is no need to untwist it.

As yet another modification, a first step of twisting the optical fiber onto a core body, a second step of untwisting, a third step of storing the composite in a pipe, and a fourth step of twisting the pipe and electric wire. Although they can be performed separately, it is preferable to perform both processes simultaneously from the viewpoint of production efficiency.

FIG. 5 is an example of a process subsequent to the process shown in FIG. It is to be stored continuously inside.

When the anti-slip object 12 is attached, the fixing part 10 is not really necessary and may be omitted.

FIG. 6 shows a structural example in which the fixing part 10 is omitted and the anti-slip object 12 is attached. In the composite cable manufactured by the method described above, torsional stress generally remains in the optical fiber and the core.

In order to reduce residual torsional stress, it is effective to twist the optical fiber and the core in advance.

The direction and amount of pre-twisting differs depending on the subsequent twisting situation.

The positional relationship between the pipe containing the optical fiber and the electric wire can be selected as appropriate.

The manufacturing method of the present invention provides the following remarkable effects.

{11 Since it is housed in an optical fiber tube and the electric wires are simply twisted together, the electric wire and optical fiber can be easily integrated, and installation is simple without the need for special hanging tools.

21 Optical fibers are untwisted and stored in a swollen state inside the tube, so even if the wires are slightly stretched due to tension, the optical fibers will not be subjected to large tension.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 4, and FIG. 5 are explanatory diagrams showing one step in an embodiment of the present invention, and FIG. 3 is an explanatory diagram of a composite cable obtained by an embodiment of the present invention, FIG. 6 is an explanatory diagram of a structure obtained at an intermediate stage of an embodiment of the invention. 1 Three-optical fiber, 2: Core body, 3: Composite, 4: Bobbin for sending out core body, 5 Bobbin for sending out three-optical fiber, 6:
bobbin for composite body, 7: pipe, 8: electric wire, 9: fixing device, 10: fixing part, 11: slippage prevention object forming device, 12:
Slip prevention object, 13: Pipe forming device. Figure 2, figure 3, figure 4, galley figure, figure 5

Claims (1)

[Claims] 1. Twist the optical fiber 1 around the core 2, untwist it, and store the untwisted composite 3 of the core 2 and the optical fiber 1 in the pipe 7. A method for manufacturing a composite cable, which comprises twisting the pipe 7 and the electric wire 8 together. 2 Twist the optical fiber 1 to the core 2, fix the core 2 and the optical fiber 1 at appropriate intervals, then untwist it, and untwist it to remove the twisted core 2 and the optical fiber. 2. The method for manufacturing a composite cable according to claim 1, wherein the composite cable 3 with the wire 1 is housed in a pipe 7, and the pipe 7 and the electric wire 8 are twisted together.