JPH0894894A - Apparatus for producing coated optical fiber for optical fiber ribbon - Google Patents

Abstract

PURPOSE: To greatly ameliorate the degradation in the accuracy of working optical fiber ribbons by the fine dust adhered onto the coated optical fiber let off from take-up drums and to improve the working efficiency of an apparatus for producing the coated optical fiber ribbons which lets off plural coated optical fibers from the take-up drums, integrally coats these fibers with synthetic resins and works the coated fibers to the optical fiber ribbon. CONSTITUTION: This apparatus is provided with a washing device 10 by a water tank 10a just before a ribboning die 2 for integrally coating plural pieces of the coated optical fibers (f) with the synthetic resins to form the ribbons and is provided with air jet nozzles 11 between this washing device 10 and the ribboning die 2 so that high-velocity air flow is blown to the coated optical fibers (f) past the washing device 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber ribbon manufacturing apparatus for feeding a plurality of optical fiber ribbons from a winding drum, covering them all together and processing them into tape ribbons. Therefore, it is possible to remarkably improve the deterioration of the processing accuracy of the optical fiber tape due to the fine dust attached to the optical fiber core wire fed from the winding drum, and to improve the operation efficiency of the optical fiber tape manufacturing apparatus.

[0002]

2. Description of the Related Art An outline of a conventional optical fiber tape core wire manufacturing apparatus will be described with reference to FIG. A plurality of optical fiber core wires f are fed out from the feeding device 1, are made parallel to each other, and are collectively covered through a tape forming die 2 for forming a tape. The core wire T is processed. In this tape forming device, for example, a device for processing five optical fiber core wires having a diameter of 250 μm into a tape core wire having a tape thickness t ₁ of 400 μm, a so-called capsule type tape core wire,
There is an apparatus for processing a tape core wire having a tape thickness t ₂ of 270 μm, that is, a so-called edge bond type tape core wire (FIG. 3).
reference). In the former case, the processing accuracy of the tape core wire does not change significantly as the operating time elapses, but in the latter case, the processing accuracy of the tape core wire decreases as the operating time elapses, and the tape shape The tape core wire may be broken, and the tape core wire processing accuracy may be significantly deteriorated. Examine the cause in detail,
As a result of analysis, for the edge bond type tape, the thickness of the surface layer of the synthetic resin coating for forming the tape is 10 μm.
It is extremely thin, and it is substantially equivalent to joining optical fiber cores with a resin coating, so dust accumulates on the nipple of the tape forming die, which greatly affects the coating with synthetic resin and It is thought that the shape of the coating will be unstable, and the fine dust attached to the optical fiber core will attach to the entrance of the nipple of the tape die,
It has been clarified that a lump of dust adhering to the inlet of the nipple grows and the dust accumulates on the nipple of the tape forming die as the operating time elapses. Therefore, the above problem is solved by eliminating the cause of dust accumulation in the nipple. Also, in order to completely remove the minute dust attached to the optical fiber core just before the nipple, it is essential that the surface of the optical fiber tape is not scratched and oil or other coating is not left on the surface of the optical fiber core. Is a requirement.

[0003]

DISCLOSURE OF THE INVENTION The present invention is capable of completely removing fine dust adhering to the surface of an optical fiber core wire which is extremely thin (for example, 250 μm) and runs at high speed without applying an external force. The idea is to devise an optical fiber cleaning device that does not leave any liquid coating on the surface of the optical fiber.

[0004]

[Means for Solving the Problems] The measures taken to solve the above problems are constituted by the following elements (a) and (b) (see FIG. 1). (A) A cleaning device using a water tank was provided in front of the tape forming die, and (b) An air jet nozzle was provided between the cleaning device and the tape forming die.

[0005]

[Operation] The dust attached to the surface of the plurality of optical fiber core wires f fed from the delivery device 1 is removed while passing through the cleaning device 10 by the water tank 10a. Cleaning device 10
To the optical fiber core wire f passing through the air jet nozzle 11
A high-speed air stream is blown from the blower to blow off the coating film of the cleaning liquid adhering to the optical fiber core wire. Even if dust adheres to the surface of the optical fiber that has passed through the cleaning device, it is blown off together with the above coating by the high-speed air flow, so that the dust and coating are completely removed. Therefore, the optical fiber core wire on which neither dust nor liquid coating is attached is drawn into the tape forming die 2.
The cleaning liquid in the water tank of the above-mentioned cleaning device is a liquid with high cleaning ability and low viscosity such as water, alcohol, freon, trichloroethylene, etc., which may deteriorate the coating material of the optical fiber and the coating material of the tape core wire. It doesn't matter if it doesn't exist.

[0006]

Example Next, an example will be described with reference to FIG. Water is put into the water tank 10a of the cleaning device 10 and is circulated by the circulation device 20 while being filtered by the filter 21. Further, an ultrasonic wave generator 22 is attached to the cleaning device 10, whereby the water in the water tank is vibrated by ultrasonic waves to improve its cleaning ability. Two air jet nozzles 11, 11 are provided so as to face each other between the cleaning device 10 and the tape forming die 2, and a high-speed air flow is blown to both front and back surfaces of the optical fiber core wire. The length L of the optical fiber of the water tank 10a in the running direction is 300 m.
m, the depth d is 50 mm, and the total capacity is 750 m ³ . Therefore, the optical fiber core wire traveling at 100 m / min passes through the water tank 10 in 0.2 seconds, but since it passes through the cleaning liquid at a high speed of 100 m / min, the cleaning effect by the water tank 10 is high. Therefore, even if the ultrasonic wave generator is not attached, sufficient cleaning can be performed, but the cleaning ability is further improved by attaching the ultrasonic wave generator. In this embodiment, five 250 .mu.m optical fiber cores are collectively formed into a tape. A nipple opening having a thickness of 280 .mu.m and an opening width of 1300 .mu.m is used to form a tape die.
Although it is premised on the manufacturing apparatus of the optical fiber ribbon for processing into the edge-bond type tape, the diameter of the air jet nozzle 11 is 3 mm, the jetting angle is 10 degrees, and the tip of the nozzle and the optical fiber ribbon f are The distance W between them is 10 mm, and the range of about three times the width of the five optical fiber core lines f is covered by the jet airflow. The air blowing speed from the air jet nozzle 11 is 30 m / sec.
When the cleaning liquid is water, if the air blowing speed is 5 m / sec or less, the water film on the surface of the optical fiber core cannot be completely removed. Even if a minute water film remains on the surface of the optical fiber core, it will evaporate at the moment of contact with the high temperature coating resin, so no particular problem will occur, but the air blowing speed should be 20 m / s or more per second. Is desirable. When the blowing speed exceeds 200 m / s, the air flow causes the optical fiber core to vibrate, which affects the processing accuracy of the optical fiber tape.
It is important to control to 0m. In consideration of the above, the type of cleaning liquid, the air blowing speed of the air jet nozzle, etc. may be appropriately selected. The test results of the above examples are as follows. A 10-km-long tape core wire was manufactured by the optical fiber tape core wire manufacturing apparatus of the above-mentioned example, and changes in its thickness and width were measured. As a result, the minimum thickness is 270 μm, the maximum thickness is 275 μm,
The maximum and minimum differences are 5 μm, and the minimum width is 12
70 μm, maximum value is 1280 μm, difference between maximum and minimum is 10
was μm. Since this is sufficiently within the range of the tolerance of the coating thickness of 50 μm and the tolerance of the coating width of 100 μm by the tape forming die 2, it can be evaluated that the intended purpose is sufficiently achieved. Also, the length is 10k
After the tape core wire of m was manufactured, the adhesion state of dust in the nipple was investigated, but no trace of dust adhesion was found. As a comparison test with this, 0.05 per 1 m ³
A dust-rich environment in which the dust of the fiber g was suspended was intentionally created, and a similar optical fiber tape was manufactured in this environment using the conventional optical fiber tape core wire manufacturing apparatus shown in FIG. As a result, it was visually confirmed that the shape of the optical fiber ribbon was remarkably changed about 20 minutes after the start of the work. The length of the optical fiber tape core wire manufactured in the meantime is 2 km. When it was visually confirmed that the shape of the optical fiber ribbon was remarkably changed, the production was stopped and
The changes in thickness and width of the optical fiber ribbon of km were measured. As a result, the minimum value of thickness is 270 μm, the maximum value is 360 μm, the difference between maximum and minimum is 90 μm, and the minimum value of width is 1150 μm and the maximum value is 1350 μm.
The difference between the maximum and minimum values was 200 μm. This is because the tolerance of the coating thickness of the tape die 2 is 50 μm.
It is 8 times, and the difference of the coating width of 200 μm is twice the tolerance of the coating width of the tape forming die 2 of 100 μm. This is because the lumps of dust adhering to the entrance of the nipple of the tape forming die grow as the operating time of the device grows, and the optical fiber cores that are drawn in parallel in parallel for tape formation break the alignment. , Because the alignment is disturbed up and down, the optical fiber ribbon becomes thicker,
The width tends to become narrow. Further, when the state of dust adhesion inside the nipple was investigated after the production was discontinued, it was confirmed that much dust adhered to the nipple. Although this comparative test is a mock test, the result is that the shape change of the optical fiber tape core wire in a normal working environment,
The fact that the dust attached to the optical fiber core is the cause is remarkably reproduced, and from this fact, the influence of the dust attached to the optical fiber core by the manufacturing apparatus for the optical fiber ribbon of the above-mentioned example. It can be said that it represents not receiving any.

[0007]

[Effect] As is apparent from the above description, according to the present invention, the dust adhered to the optical fiber core is completely removed together with the cleaning liquid coating on the optical fiber core before being drawn into the tape forming die. As a result, it is possible to completely prevent a decrease in tape processing accuracy such as a change in shape of the optical fiber tape. Therefore, it is possible to improve the processing accuracy and reliability of the optical fiber tape, and significantly improve the optical fiber tape manufacturing efficiency, manufacturing efficiency, and operation efficiency of the optical fiber tape manufacturing apparatus, thus reducing the manufacturing cost of the optical fiber tape. Can greatly contribute to Before being pulled into a tape die, it is common to wipe the optical fiber core wire with a soft sponge (sponge) to remove dust adhering to the surface of the fiber core wire. . However, although it is possible to remove extremely large dust by this, it is not possible to completely remove fine dust,
Also, dust accumulates on the contact surface of the sponge with the optical fiber core, grows, and eventually peels off and is drawn into the tape forming die. Since this is repeated as the operating time of the optical fiber tape manufacturing apparatus elapses, a change in the shape of the optical fiber tape cannot be avoided within a long time. In the present invention, the above effects are remarkable even when compared with such a conventional technique. Further, the apparatus of the present invention requires almost no maintenance, the above effects can be maintained for a long time, and since there is no consumable item, the operating cost does not increase. This is a great advantage of the present invention.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an embodiment of the present invention.

FIG. 2 is a conceptual diagram of a conventional technique.

FIG. 3A is a cross-sectional view of a capsule type optical fiber tape core wire, and FIG. 3B is a cross-sectional view of an edge bond type optical fiber tape core wire.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Delivery device 2 ... Tape forming die 3 ... Ultraviolet irradiation device 10 ... Cleaning device 10a ... Water tank 11 ... Air jet nozzle 20 ... Circulation device 21 ... Filter 22・ ・ ・ Ultrasonic wave generator f ・ ・ ・ Optical fiber core wire T ・ ・ ・ Optical fiber tape f ・ ・ ・ Depth of water tank w ・ ・ ・ Gap between nozzle tip and optical fiber core wire t ₁ , t ₂・..Tape thickness

Claims (1)

[Claims] Claim: What is claimed is: 1. A plurality of optical fiber core wires are fed out from a delivery device, and are made parallel to each other and are collectively covered through a tape forming die for forming a tape, and the coating is cured through an ultraviolet irradiation device. In an optical fiber tape core manufacturing apparatus for manufacturing a tape core wire, a cleaning device with a water tank is provided in front of the tape forming die, and an air jet nozzle is provided between the cleaning device and the tape forming die to perform the cleaning. An optical fiber ribbon core manufacturing apparatus that blows a high-speed air stream onto the optical fiber core that has passed through the device.