JPS6126333Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to a coupling agent coating device for optical fiber.

(Technical background and problems) During the manufacturing process of optical fibers, in order to increase the strength of the optical fibers, the surface of the optical fibers is coated with a thin layer of resin immediately after spinning the optical fibers. This coating is called a primary coat, and the strength of the optical fiber is increased by 4 to 6 times. Various resins such as fluorine-based, acrylic-based, and epoxy-based resins are used as the coating resin. Regardless of which resin is used, heating is applied immediately after coating to crosslink or dry the resin to improve the strength of the optical fiber.

However, in the above coating, it is essential that the adhesion between the resin and the optical fiber (glass) be good, and a silane coupling agent is usually used to improve the adhesion. (For example, see JP-A-50-137151.) This silane coupling agent is used to improve adhesion by forming a bond between the glass and the resin, but the coating with the resin is usually done using a die. When using a resin or a coupling agent that equalizes the crosslinking or drying temperature, dice coating is performed using a mixed solution of the resin and the coupling agent.
However, the crosslinking or drying temperatures of the resin and coupling agent are usually different, and the above method cannot generally be used. In such a case, a two-stage process is required, such as coupling agent application→drying→resin application→drying.

Since the coupling agent has a very low viscosity, it cannot be applied using a die in the above process, and is instead applied using a felt die or brush, but these methods do not provide sufficient uniformity. Moreover, it is difficult to apply a thin coating.

(Purpose of invention) 〓〓〓〓
The present invention was devised in view of the above circumstances, and provides an optical fiber coupling agent coating device capable of uniformly and thinly coating a low-viscosity coupling agent.

(Summary of the invention) A hollow cylindrical device casing having two inner cylinders that are open at the upper and lower end faces and end oppositely inside the casing, and a hollow cylindrical device casing that has two inner cylinders that are open in the side wall of the device casing and whose axial position is between the ends of the two inner cylinders. A light characterized by having a plurality of inert gas injection ports aligned with the voids, and a plurality of thin tubes whose upper ends are aligned with each other near each inert gas injection port and are provided parallel to the housing axis. Fiber coupling agent coating equipment.

(Embodiments of the invention) The details of the invention will be explained below with reference to the drawings. In the figure, a hollow cylindrical device housing 1 has an opening at the center of both end faces, and two inner cylinders 2, which terminate inside the housing.
It has 3. Inert gas inlets 5 and 6 are opened at both diametrical ends of the casing 1, with axial positions aligned with the inner cylinders 2 and 3 and the gap 4 between the ends. Thin tubes 7 and 8 are provided in the casing 1 with their upper ends located near the respective injection ports 5 and 6 and parallel to the casing axis.

A coupling agent 9 is contained in the housing 1 in an amount sufficient to soak the lower ends of the thin tubes 7 and 8.

In the apparatus of the present invention having the above structure, the coupling agent 9 is applied as follows. That is,
The optical fiber 10 passes through the inner tubes 2 and 3 and runs from top to bottom. Inert gas such as nitrogen N ₂ is injected from the gas injection ports 5 and 6 under pressure.
Then, the coupling agent 9 is sprayed in the form of a mist from the upper ends of the thin tubes 7 and 8 toward the optical fiber 10 for coating.

(Effect of the invention) In the present invention described above, since the amount of application can be controlled by the gas flow rate, the amount of application can be easily and arbitrarily set.

Furthermore, since there is no part that comes into direct contact with the optical fiber during coating, there is no risk of mechanical damage or contamination of the optical fiber.

Note that the present invention is not limited to the above-mentioned embodiment, and for example, the number of inert gas injection ports may be three or more.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of the present invention, and FIG. 2 is a cross-sectional view thereof. 1... Housing, 2, 3... Inner cylinder, 4... Gap between ends, 5, 6... Gas inlet, 7, 8... Thin tube, 9
... Coupling agent, 10 ... Optical fiber. 〓〓〓〓

Claims (1)

[Scope of utility model registration request] A hollow cylindrical device casing having two inner cylinders that are open at the upper and lower end faces and end oppositely in the casing, and an opening in the side wall of the device casing whose axial position coincides with the gap between the ends of the inner cylinders. A coupling agent coating for optical fiber characterized by having a plurality of inert gas injection ports and a plurality of thin tubes whose upper ends coincide with each other near each inert gas injection port and are provided parallel to a housing axis. Device.