JPS6023326B2 - Manufacturing method of optical fiber with metal pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an optical fiber containing a metal pipe,
In particular, the present invention relates to a manufacturing method in which optical fibers are statically and stably held during the tube manufacturing process.

In order to manufacture optical fibers in metal pipes, a method has already been proposed in which the optical fibers are inserted into the metal pipes during a tube manufacturing process such as roll forming, but in such methods, the optical fibers are simply inserted. Therefore, as shown in FIG. 1, the optical fiber 1 is not in a stable position within the pipe 2 or just before being formed into the pipe 2.
In addition, since the diameter is very small compared to the diameter of the pipe 2, it is easily shaken, and therefore it may come into contact with the forming roll for pipe making, or come into contact with or wrap around the gas pipe 3 into which shielding gas is injected, resulting in mechanical damage. In addition, the welding equipment 4 is often damaged in the welding process.
This had the disadvantage that the arc from the fiber could fly off and thermally damage the optical fiber.

The present invention attempts to solve the above-mentioned drawbacks by vertically attaching optical fibers to a metal tape and forming a pipe from the metal tape while maintaining the vertically attached state. To explain this, in FIG. 2, one optical fiber feeding means is used to supply the optical fiber 1, 12 is a tape feeding means for feeding the metal tape 13, and 14 is a tape feeding means for feeding the metal tape 13 onto the metal tape 13. , which is a guide roll that is arranged at an interval described later from the tape 13 and is rotatable in the longitudinal direction of the tape 13, and the optical fiber 11 fed from the optical fiber feeding means 10 is guided by the optical fiber feeding means 10. 10 and the guide roll 14, and is guided by an intermediate roll 15 disposed between the guide roll 14 and the metal tape 13.

The distance between the guide roll 14 and the metal tape 13 is set so that the optical fiber 1 passing between these two 14 and 13 is frictionally engaged with the two, and the guide roll 14 is made of a metal tape 13 as shown in FIG. , optical fiber 11
It is preferable that the optical fiber 11 is provided with a circumferential groove 16 that can be slidably engaged with the metal tape 13, thereby reliably preventing the optical fiber 11 from shifting in the width direction of the metal tape 13. It will be attached vertically along the line.

A metal tape 13 is used as a pupil for the guide roll 14.
It is preferable that the optical fiber 11 be located at approximately the center in the width direction of the metal tape 13. By doing this, the optical fiber 11 will be longitudinally attached to the approximately center in the width direction of the metal tape 13. It will be located at the bottom of the formed pipe 17 during pipe making, which will be described later, and as a result, the fiber 11 will be stably held at the bottom by its own weight.

Further, the outermost coating of the optical fiber 11 is preferably nylon or Teflon, and the material of the guide roll 14 is preferably nylon, Teflon or hard rubber. When these are used, the feeding speed of the optical fiber 11 and the guide roll When the rotational speeds of the optical fibers 14 and 14 are made different, the outermost coating layer of the optical fiber 11 will be slightly charged due to friction with the guide roll 14, and will adhere well to the metal tape 13.

Therefore, as described above, the guide roll 14 is connected to the metal tape 13.
Even if the optical fiber 11 is not placed approximately at the center in the width direction of the pipe, the optical fiber 11 will be adhered and held to the formed pipe 17 during pipe forming, and will not sway or the like.

The metal tape 13 on which the optical fiber 11 is longitudinally attached as described above is fed to a pipe forming process, preferably a roll forming process, where rolling rolls 18, 18, . . .
Then, as shown in FIG. 4, the joint of the formed pipe 17 is fused by a welder 19. As explained above, the present invention vertically attaches optical fibers along the longitudinal surface of a metal tape supplied to a pipe making process, and while maintaining the longitudinally attached state, the metal tape is circularly attached in the pipe making process. In a method for manufacturing an optical fiber in a metal pipe, which is formed into a tubular shape and attached to the joint of the formed pipe by welding, a guide rail is arranged on the metal tape so as to be rotatable in the longitudinal direction of the tape, When the optical fiber passes between the metal tape and the guide roll, the metal tape and the optical fiber are charged by the relative friction between them, and the optical fiber is bonded to the approximate center of the metal tape in the width direction. , is characterized by welding the joints of a molded pipe made of metal tape.

Therefore, in the case of the present invention, since the optical fiber is properly and stably held on the metal tape by charged adhesion,
During pipe making and joint welding of formed pipes, optical fibers may escape from their designated positions or come into contact with rolling rolls.
Furthermore, the optical fiber does not get wrapped around the shielding gas pipe, and especially during joint welding, the optical fiber is located within the formed pipe and settled at a position far from the joint, so it is less susceptible to the effects of welding. It does not cause characteristic deterioration due to welding heat or fire.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the state of the optical fiber during conventional pipe manufacturing, and FIG. 2 is a process explanatory diagram of the manufacturing method according to the present invention.
FIG. 3 is a front view of a guide roll used in the same process, and FIG. 4 is a perspective view showing the state of the optical fiber during pipe production in the same process. 11... Optical fiber, 13... Metal tape, 17... Formed pipe, 19... Welding machine. Figure 1 Figure 2 Figure 3 Figure 3

Claims (1)

[Claims] 1. Optical fibers are vertically attached along the longitudinal surface of a metal tape supplied to a pipe making process, and while maintaining the vertically attached state, the metal tape is formed into a circular tube shape through the pipe making process, and the forming In a method for manufacturing optical fibers with metal pipes in which pipe joints are fused by welding, a guide rail is arranged on the metal tape so as to be rotatable in the longitudinal direction of the tape, and these metal tapes and guide rolls are When the optical fiber passes between the metal tape and the optical fiber, the metal tape and the optical fiber are electrically charged by the relative friction between them, and the optical fiber is charged and adhered to the approximate center in the width direction of the metal tape.
Thereafter, the joints of the formed pipe, which is a molded product of metal tape, are welded.