JPH0327497B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in an apparatus for manufacturing optical fiber by drawing an optical fiber base material and coating it with resin.

(Prior Art) In general, this type of optical fiber manufacturing apparatus includes a drawing means for drawing an optical fiber base material while heating it in a heating furnace to form an optical fiber core wire, and a method for applying a resin to the optical fiber core wire. A resin application means such as a coating die, a crosslinking means for crosslinking the optical fiber core wire coated with resin by the resin application means, and an optical fiber fed out from the crosslinking means is taken up and wound. A winding means is provided. In this device, if the distance from the drawing means to the resin coating means is increased in order to cool the optical fiber core wire drawn out from the drawing means, the optical fiber core wire is separated between the drawing means and the resin coating means. Vibration occurs, and as a result, the surface of the optical fiber core wire is damaged by the surface of the coating die, resulting in breakage or deterioration of strength, as well as variations in the circularity and coating thickness of the optical fiber. Furthermore, if the distance between the line drawing means and the resin application means is long, the height of the equipment will increase, which increases the height of the building in which this equipment is housed, resulting in higher equipment costs. Ta. especially,
This tendency becomes even more pronounced when the drawing and coating speeds are increased, resulting in higher equipment costs and lower product quality.

(Object of the Invention) An object of the present invention is to manufacture an optical fiber that can improve product quality and reduce equipment costs by preventing vibration between the drawing means and the resin application means. The goal is to provide equipment.

(Structure of the Invention) The optical fiber manufacturing apparatus according to the present invention includes a drawing means for drawing an optical fiber base material while heating it to form an optical fiber core wire, and a resin coating device for applying a resin to the optical fiber core wire. a crosslinking means for crosslinking the optical fiber core wire coated with a resin by the resin coating means; and a winding means for winding the optical fiber core wire fed out from the crosslinking means while taking it up. However, it is characterized in that it further includes a vibration prevention roll installed upstream of the resin application means to prevent vibration of the optical fiber core wire.

In this way, even if the optical fiber core wire is cooled over a long distance between the drawing means and the resin application means, vibration will not occur in the optical fiber core wire, and therefore the quality of the product will not deteriorate. Moreover, by preventing this vibration, the running direction of the optical fiber core wire can be easily changed, the height of the equipment can be reduced, and the equipment cost can therefore be reduced.

(Example) An example of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an optical fiber manufacturing apparatus 10 according to the present invention, and this optical fiber manufacturing apparatus 10 is equipped with a holding means (not shown). a drawing means 18 for forming an optical fiber core wire 14 by drawing an optical fiber preform 12 held vertically in a heating furnace 16 while heating it in a heating furnace 16;
a resin application means 20 for applying resin to the optical fiber core wire 14 fed out from the optical fiber core wire 14;
Optical fiber core wire 14 coated with resin by 0
The optical fiber 14A is provided with a crosslinking means 22 for crosslinking the upper resin, and a winding means 28 for winding the optical fiber 14A drawn out from the crosslinking means 22 onto a winding bobbin 26 while being taken up by a winding machine 24. In the illustrated embodiment, two stages of resin application means portions 20A and 20B and crosslinking means 2 are shown.
2A and 22B are provided to form a two-layer coating, however, these may be formed into one stage and may be a single-layer coating.

As shown in FIGS. 2A and 2B, the resin application means 20 consists of a resin tank 30 through which the optical fiber core wire 14 passes, and this resin tank 30 has the optical fiber core wire 14 liquid-tightly inserted at the entrance and exit of the resin tank 30, respectively. It has an entrance die (not shown) and a coating die (exit die) 32 extending therethrough. The entrance die has an inner diameter slightly larger than the outer diameter of the optical fiber core wire 14, and has the function of preventing the resin in the resin tank 30 from flowing out and minimizing the entrainment of air. On the other hand, the coating die 32 has an inner diameter that sets the thickness of the resin to be coated on the optical fiber 14.
4 is coated with a predetermined thickness. Further, the resin tank 30 is formed so that its horizontal cross-sectional area is larger than its vertical cross-sectional area, and can be rotated by 90 degrees around the traveling path of the optical fiber core wire 14.
As can be seen from FIG. 2A, when the resin bath 30 is in a horizontal position, the resin liquid 34 is applied to the optical fiber core wire 14.
However, as shown in FIG. 2B, when the resin tank 30 rotates until it reaches the vertical position, the liquid level 34a of the resin liquid 34 rises above the traveling path, and the resin liquid 34 touches the optical fiber. It adheres to the core wire 14.
In FIG. 2, reference numeral 38 is a flexible resin liquid supply pipe for replenishing the resin tank 30 with resin liquid from a resin supply source (not shown). The resin to be adhered to the optical fiber core wire 14 is preferably an ultraviolet curing resin, for example. Further, the crosslinking means 22 consists of an ultraviolet irradiation lamp when the resin attached to the optical fiber core wire 14 is an ultraviolet curable resin.

In this device, an optical fiber base material 12 is heated in a heating furnace 16.
When the optical fiber core wire 14 is heated and taken off by the take-up machine 24 of the take-up means 28, the optical fiber core wire 14 is taken up and drawn downward in proportion to the amount of wire drawn. The optical fiber core wire 14 enters the first-stage resin application means 20A from the wire drawing means 18, is coated with an ultraviolet curable resin, and is cross-linked by the next first-stage cross-linking means 22A to form the first layer. A coating is formed, and a second layer of coating is similarly formed through the second stage resin application means 20B and crosslinking means 22B. The resin application means 20A and 20B are placed in a horizontal position as shown in FIG.
The resin tank 30 is rotated to a vertical position as shown in Figure B. The optical fiber 14A thus formed is taken up by a take-up machine 24 and wound onto a take-up bobbin 26.

The optical fiber manufacturing apparatus 10 of the present invention is installed upstream of the resin coating means 20, and the optical fiber core wire 14
It further includes an anti-vibration roll 36 for preventing vibrations. This anti-vibration roll 36 is preferably made of a material such as urethane resin to which the optical fiber core wire 14 will not adhere.

In this way, even if the optical fiber core wire 14 is cooled over a long distance between the drawing means 18 and the resin coating means 20, the optical fiber core wire 14 will not vibrate due to the anti-vibration roll 36. Therefore, the optical fiber core wire 14 will not be damaged by the surface of the coating die 32, causing breakage or deterioration in strength, and variations in the circularity and coating thickness of the optical fiber 14A will not occur, resulting in a product. quality will improve.

FIG. 3 shows another embodiment of the invention, in which the optical fiber 14 is provided with an anti-vibration roll 36.
The direction has been changed by 90°. In this way, since the resin application means 20 and the bridging means 22 are arranged horizontally, the height of the equipment can be small, and therefore the height of the building that houses them can also be small, and the equipment cost can be reduced. Therefore, it is preferable.

(Effects of the Invention) According to the present invention, as described above, there is a practical benefit in that the generation of vibration between the wire drawing means and the resin application means can be prevented and the quality of the product can be improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic system diagram of an optical fiber manufacturing apparatus according to the present invention, FIGS. 2A and B are sectional views of different states of the resin coating means used in the present invention, and FIG. 3 is another embodiment of the present invention. FIG. 2 is an example schematic diagram. 10... Optical fiber manufacturing device, 12... Optical fiber base material, 14... Optical fiber core wire, 14A...
Optical fiber, 16... heating furnace, 18... wire drawing means, 20, 20A, 20B... resin coating means, 2
2, 22A, 22B...Bridging means, 24...Take-up machine, 26... Winding drum, 28... Winding means, 3
0...Resin tank, 32...Coating die, 34...Resin liquid, 36...Vibration prevention roll, 38...Resin liquid supply pipe.

Claims (1)

[Scope of Claims] 1. A drawing means for drawing an optical fiber base material while heating it to form an optical fiber core wire, a resin application means for applying a resin to the optical fiber core wire, and the resin application means. An optical fiber manufacturing apparatus comprising a crosslinking means for crosslinking an optical fiber core wire coated with a resin, and a winding means for taking up and winding the optical fiber fed out from the crosslinking means. An optical fiber manufacturing apparatus further comprising a vibration prevention roll installed on an upstream side to prevent vibration of the optical fiber core wire. 2. The optical fiber according to claim 1, wherein means below the resin application means are arranged so that the optical fiber core wire is direction-changed by the vibration prevention roll and guided to the resin application means. Manufacturing equipment. 3. The optical fiber manufacturing apparatus according to claim 1 or 2, wherein the resin application means comprises a resin bath through which the optical fiber core wire passes and rotates around a travel path of the optical fiber core wire. .