JPH01275450A - Vertical device for producing coated optical fiber - Google Patents

Abstract

PURPOSE:To reduce preparatory working time and to improve working efficiency by stopping the supply of resin to a pressurized die by the signal from a disconnection detecting means, and recovering the resin in the die in a recovery tank when a fiber is broken. CONSTITUTION:The device for producing a coated optical fiber is composed of a pressurized tank 12 for supplying resin 5 to the pressurized die 4, a pressure source 14 for pressurizing the tank 12, a pressure control valve 16 provided to a pressurizing passage 15 extending from the source 14 to the tank 12, the recovery tank 19, a vacuum pump 24 for evacuating the tank 19, and the disconnection detecting means 11. The liq. resin 5 in the pressurized die 4 is recovered in the recovery tank 19. When the breaking of a fiber 3A is detected by the detecting means 11, the pressure control valve 16 is closed, and a recovery control valve 20 provided to a recovery passage 18 is opened by the signal from the detecting means 11.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves passing an optical fiber spun from an optical fiber preform through a pressurizing die on the way down, and applying a resin liquid to the surface of the die under pressure. The present invention relates to a vertical optical fiber manufacturing apparatus in which the coated optical fiber is coated with a coating resin and the obtained optical fiber is passed through a resin curing device under the pressure die to cure the coating resin.

[Prior art] With the increase in the speed of optical fiber core manufacturing, a pressure die is used as a resin coating means to coat the surface of the optical fiber with pressurized resin liquid. This allows the wire to be well coated with the resin liquid.

[Problems to be Solved by the Invention] However, in such conventional vertical optical fiber core manufacturing equipment, when the optical fiber wire breaks, pressurized resin liquid spouts out from the hole in the pressure die. This has the problem of contaminating resin curing equipment such as a baking furnace or an ultraviolet irradiation equipment located below, which significantly impedes setup work and reduces work efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vertical optical fiber core manufacturing apparatus that can prevent a resin curing apparatus from being contaminated by resin ejected from a pressure die when an optical fiber strand is broken.

[Means for Solving the Problems] To explain in detail the present invention for achieving the above-mentioned object, the present invention applies pressure while lowering an optical fiber strand formed by spinning from an optical fiber preform. A vertical optical fiber coated wire that is passed through a die, its surface is coated with a resin liquid under pressure, and the obtained coated optical fiber is passed through a resin curing device below the pressure die to cure the coated resin. In the manufacturing apparatus, a pressurizing tank containing the resin liquid to be coated on the optical fiber strand and supplying the resin liquid to the pressurizing die via the resin supply path by pressurizing the resin liquid, and the pressurizing tank a pressurization source that pressurizes the inside, a pressurization control valve provided in a pressurization passage from the pressurization source to the pressurization tank, and a pressurization control valve that collects the resin liquid in the pressurization die through a recovery passage. A recovery tank to be recovered, a recovery control valve provided in the recovery passage, a vacuum pump that evacuates the inside of the recovery tank, and when a break in the optical fiber is detected, the pressurization control valve is closed. The present invention is characterized by comprising wire breakage detection means for outputting a signal to the recovery control valve.

[Function] With this structure, if the optical fiber wire breaks, the pressurization control valve becomes a lever and the supply of resin liquid from the pressurization tank to the pressurization die is stopped, and the recovery control When the valve is opened, the resin liquid in the pressurizing die is evacuated and collected in the collection tank.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

As shown in the figure, an optical fiber preform 1 is heated and spun in a heating furnace 2, and optical fiber strands 3A are sequentially formed, which are lowered and passed through a pressure die 4.

In the pressure die 4, the surface of the optical fiber 3A is coated with one or more layers of pressurized resin liquid 5, and the optical fiber core 3A is coated with one or more layers.
is obtained. A resin curing device 6 such as a baking oven or an ultraviolet irradiation device is provided below the pressure die 4 for curing the coating resin on the surface of the optical fiber core 3 . After the outer diameter of the optical fiber core 3 whose coating resin has been cured is measured using an outer diameter measuring device 7, it is taken off by a take-up machine 8 and turned horizontally, and passed through a dancer device 9. It is adapted to be wound up by a winding machine 10. The rollers of the dancer device 9 are provided with the dancer roll 9 when the optical fiber wire 3A is broken.
Disconnection detection means 11 is provided, which is a limit switch that detects disconnection of the optical fiber 3A by utilizing the downward movement of A. The resin liquid 5 in the pressure tank 12 is supplied to the pressure die 4 via a resin supply path 13. The resin liquid 5 in the pressurized tank 12 is pressurized by a pressurized gas such as N2 gas supplied from a pressure source 14 through a pressurizing passage 15, and the resin liquid 5 is supplied to the pressurizing die 4 through the resin supply passage 13 by the pressure. is being supplied to. A pressure control solenoid valve 16 is connected to the pressure passage 15 as a pressure control valve. A pressure relief solenoid valve 17 is connected to the pressurized tank 12 as a pressure relief valve. A recovery tank 19 is connected to the pressure die 4 to recover the resin liquid 5 therein via a recovery passage 18 . A recovery control solenoid valve 20 is connected to the recovery passage 18 as a recovery control valve. The resin liquid 6 recovered in the recovery tank 19 is returned to the pressurized tank 12 via a recovery liquid return passage 21. A valve 22 is connected to the recovered liquid return passage 21 to collect the recovered resin liquid 6.
It is designed to be opened only when returning. A vacuum pump 24 is connected to the recovery tank 19 via a vacuum passage 23. A pressure regulating valve 25 is connected to the vacuum passage 23 . The signal from the disconnection detection means 11 is applied to the pressurizing side m solenoid valve 16, the pressure relief solenoid valve 17, and the recovery control solenoid valve 20.

In such a vertical optical fiber manufacturing apparatus, when the optical fiber wire 3A is broken, the dancer circle 9△ is lowered, whereby the breakage detection means 11 detects the breakage and outputs a breakage detection signal. is applied to the solenoid valve 16.17.20. As a result, the solenoid valve 16 closes to stop the supply of pressurized gas to the pressurized tank 12, and the solenoid valve 17 opens to release the pressure inside the pressurized tank 12, and the resin liquid 5 is Stop pressurizing. Furthermore, the electromagnetic valve 20 is opened to evacuate the pressurizing die 4, and the resin liquid 5 in the pressurizing die 4 is recovered into the recovery tank 19. In this case, it is preferable to operate the vacuum pump 24 in advance to speed up the response.

According to such a device, the resin liquid 6 is prevented from spouting or flowing downward from the pressure die 4 when the optical fiber wire 3A is broken.

Note that the outer diameter measuring device 7 can also be used as the wire breakage detection means.

Moreover, as a matter of course, the coating resin liquid 6 also includes a coloring resin liquid such as ink.

[Effects of the Invention] As explained above, in the optical fiber manufacturing apparatus according to the present invention, when the optical fiber wire is broken, the pressurization control valve is opened in response to a signal from the breakage detection means, and pressure is applied from the pressurized tank. The supply of resin to the pressure die is stopped, and the recovery control valve is opened to vacuum the resin in the pressure die and collect it in the recovery tank. This prevents resin liquid from the pressure die when the optical fiber wire breaks. It is possible to prevent the resin curing device from being contaminated by the ejected resin, reduce setup work time, and improve work efficiency.

[Brief explanation of the drawing]

The drawing is a schematic configuration diagram of an embodiment of a vertical optical fiber core manufacturing apparatus according to the present invention. 1... Optical fiber base material, 2... Heating furnace, 3A...
Optical fiber strand, 3... Optical fiber core wire, 4... Pressure die, 5... Resin liquid, 6... Resin curing device, 7
・・・Outer diameter measuring device, 8... Taking machine, 9... Dancer
Apparatus, 9A... dancer roll, 10... winding machine,
11... Disconnection detection means, 12... Pressurized tank, 13
... Resin supply path, 14... Pressure source, 15... Pressure passage, 16... Pressure control solenoid valve (pressure control valve), 19
...Recovery tank, 20...Recovery control solenoid valve (recovery control valve), 23...Evacuation passage, 24...Vacuum pump.

Claims (1)

[Claims] The optical fiber wire formed by spinning from the optical fiber base material is passed through a pressure die on the way down, and its surface is coated with a resin liquid under pressure, and the obtained optical fiber core wire is subjected to the pressure. In a vertical optical fiber core manufacturing apparatus in which the coating resin is cured by passing it through a resin curing device under a die, the resin liquid to be coated on the optical fiber strand is contained and the resin liquid is pressurized. A pressurizing tank that supplies the resin to the pressurizing die via a resin supply path, a pressurizing source that pressurizes the inside of the pressurizing tank, and a pressurizing path that leads from the pressurizing source to the pressurizing tank. a recovery tank that recovers the resin liquid in the pressure die through a recovery passage; a recovery control valve provided in the recovery passage; and a vacuum that evacuates the inside of the recovery tank. A vertical optical fiber core comprising: a pump; and a disconnection detection means that closes the pressurizing control valve and outputs a signal to interrogate the recovery control valve when detecting a disconnection of the optical fiber strand. Line manufacturing equipment.