JPS598982Y2 - Resin coating equipment for optical transmission lines - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of a resin coating device for an optical transmission line, and particularly relates to a resin coating device in which an auxiliary container for replenishing the resin is attached above a main container for accommodating a resin material. .

In order to manufacture glass optical fibers known as optical fibers, a gas phase chemical reaction (
It is common practice to produce a high-purity glass base material by CVD (CVD method), heat and stretch the glass base material, and then spin it into an optical transmission line with a desired outer diameter.

However, the optical transmission line obtained by heating and stretching the glass base material and spinning it into a fiber is weak in strength, and it is difficult to maintain a low transmission loss due to the adhesion of dust or easy scratches on the outer surface.

Therefore, in order to protect the surface of such an optical transmission line, a resin coating called a primary coating with silicone resin or the like is applied immediately after the optical transmission line is spun.

A sectional view of a main part of a conventional resin coating device for optical transmission lines used for such resin coating is shown in FIG. 1a.

Reference numeral 1 denotes an optical transmission line spun to a desired outer diameter, 2 a main container housing the coating resin material 3, and 11 a primary coated optical transmission line drawn out from the lower end nozzle portion 2a of the main container 2. .

In such a structure, the resin material 3 for the main container 2
Conventionally, the replenishment of replenishment was carried out artificially, for example, by putting the replenishing resin material into a Nolasco or the like and replenishing it simultaneously from directions A and B shown by the arrows. Since 3 is a high viscosity liquid, it is difficult to avoid the liquid surface in the main container 2 from fluctuating during and immediately after replenishment.

When the surface of the liquid is shaken in this manner, the optical transmission line 1 is deviated from the center of the main container 2 and becomes temporarily offset.

If such an eccentric state occurs during continuous spinning of a long transmission line, the cross section of the primary coated transmission line 11 coated at that part will have an eccentric shape as shown in Figures 1b and 1C. Become.

Furthermore, when replenishing the resin material 3, the resin material entrains bubbles, resulting in bubbles being included around the optical transmission line 1 and in the coating, increasing the loss of the optical transmission line and weakening the eccentric part. There were drawbacks.

The present invention was made to solve the above-mentioned drawbacks, and attempts to prevent the liquid surface from fluctuating due to replenishment of the resin material by providing an auxiliary container for the resin material above the main container containing the resin material. It is something.

Briefly stated, the present invention provides a resin coating device for an optical transmission line for inserting an optical transmission line spun to a desired outer diameter and applying a resin coating to the surface of the optical transmission line. An auxiliary container for replenishing the resin material is provided above the main container, and a plurality of supply pipes connected to the auxiliary container are opened at symmetrical positions with respect to the optical transmission line in the main container. .

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin coating device for optical transmission lines according to the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a cross-sectional view of essential parts showing an embodiment of the resin coating device for optical transmission lines according to the present invention, and the same parts as those in the previous figure are designated by the same reference numerals.

4 is two auxiliary containers that contain the resin material 3, 5 is a supply pipe that supplies the resin material 3 from each auxiliary container 4 to the main container 2, and 6
is a replenishment amount adjustment roller that adjusts the replenishment amount of the resin material 3.

In the illustrated example, the two supply pipes 5 are the optical transmission lines 1 to be covered.
It opens into the main container 3 at a symmetrical position with respect to the center, and the amount of replenishment from both replenishment pipes can be adjusted to be substantially the same by an adjustment roller 6.

With this configuration, the resin material 3 is transferred from the auxiliary container 4 to the main container 2 via the supply pipe 6 depending on the amount used.
The liquid level of the resin material 3 in the main container 2 is kept constant at all times.

In this case, the supply amount of resin material 3 is small (total supply amount 1
cc/min), and since the plurality of replenishment pipes 6 are arranged at symmetrical positions with respect to the optical transmission line in the main container 2, there is almost no fluctuation in the liquid level due to replenishment of the resin material 3.

Therefore, uneven thickness of the primary coating is eliminated, and since a small amount of replenishment as described above is carried out continuously, there is no risk of bubbles being drawn in.

In the above embodiment, a device in which two auxiliary containers 4 were symmetrically provided was described, but only one auxiliary container may be used in common with a plurality of supply pipes. A plurality of continuous supply pipes 5 are connected to the optical transmission line 1 in the main container 2.
The feature is that the openings are arranged at symmetrical positions with respect to the center to prevent offset of the optical transmission line due to resin replenishment.

It is also possible to provide a liquid level detection sensor to keep the liquid level in the main container 2 constant, and to connect a replenishment amount adjusting roller to this sensor to automatically control the replenishment amount.

As explained above, according to the resin coating device for optical transmission lines of the present invention, it is possible to prevent the liquid level in the main container from fluctuating due to replenishment of the resin solution, and there is no risk of bubbles being drawn in during replenishment, so high quality can be achieved. Since the optical transmission line can be primarily coated, it is extremely useful for application to the optical transmission line spinning process.

[Brief explanation of the drawing]

Fig. 1 shows a conventional resin coating device for optical transmission lines, a is a side sectional view of the main container, b and C are sectional views of the primary coated optical transmission line, and Fig. 2 is an optical transmission line according to the present invention. FIG. 1: Optical transmission line, 2: Main container, 3: Resin material, 4: Auxiliary container, 5: Supply pipe, 6: Supply amount adjustment roller, 11: Next coated optical transmission line.

Claims (1)

[Scope of utility model registration request] In an optical transmission line resin coating device for inserting an optical transmission line spun to a desired outer diameter and applying resin coating to its surface, an auxiliary resin material supplying device is installed above the main container containing the resin material. A resin coating device for an optical transmission line, characterized in that a container is provided, and a plurality of supply pipes connected to the auxiliary container are opened at symmetrical positions with respect to the optical transmission line in the main container.