JP2000231043A - Coated optical tape, its production and dice for production of coated optical tape used for that method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the process of a pick finding easy, accurate and safe, and to obtain good connection in an optical connector by coating two optical fibers apart from and parallel to each other together with a resin to obtain a coated optical tape in such a manner that the center regions of the both flat faces of the tape project along the longitudinal direction. SOLUTION: A coated optical tape 1 is produced by coating two optical fibers 2 apart from and parallel to each other together with a coating layer 3 into a tape, and the tape 1 has a connecting region 3a to connect the optical fibers 2 with each other and a fiber region 3b where the each optical fiber 2 is coated. The connecting region 3a has thickness A in the perpendicular direction to a plane X which crosses the center C of each cross section of plural optical fibers 2. The fiber region 3b includes the cross section center C of the each optical fiber 2 and thickness B in the perpendicular direction to the plane X. In the optical tape 1, the thickness A in the connecting region 3a is made larger than the thickness B in the fiber region 3b.

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 having a cross-sectional structure suitable for indoor wiring and the like, which is easy to work out, a method of manufacturing the same, and a die used for the manufacture thereof.

[0002]

2. Description of the Related Art In general, an optical fiber ribbon is generally formed by arranging a plurality of optical fiber wires in parallel with each other in a state of being in contact with each other and forming a coating layer made of an ultraviolet curable resin or the like around the optical fiber wires. Are integrated into a tape.
Such an optical fiber ribbon can handle a plurality of optical fiber wires collectively, and since a plurality of optical fiber wires can be connected collectively, the connection time is short, and work efficiency is reduced. Is good. Further, since the size of the optical fiber can be reduced as compared with the case where the optical fiber is separately formed into a core, there is an advantage that high-density mounting of the optical fiber can be achieved.

By the way, in a multi-core optical connector used in a wiring system such as a LAN or indoors or between equipments, the spacing between optical fibers in the connector is limited by the optical fiber element in the optical fiber ribbon due to the system standard. It is much wider than the spacing between lines. For this reason, when a general optical tape core is connected to a multi-core optical connector in such a system and used as a wiring optical cord or the like, each optical fiber is separated from the optical tape core and further separated. In addition, it is necessary to attach a jumper cord for matching the fiber interval in the multi-fiber optical connector to each of the separated strands.

Therefore, as shown in FIG. 6, there has been proposed an optical fiber ribbon 1 in which a plurality of optical fiber wires 2 are covered and integrated with a coating layer 3 while being separated from each other. FIG.
As is clear from FIG. 1, the optical fiber ribbon 1 has a connecting portion 3a for connecting the optical fiber wires 2 and a wire portion 3b covered with the optical fiber wire 2, and the optical fiber ribbon. 1
The thickness of the connecting portion 3a is made smaller than the thickness of the wire portion 3b in order to improve the mechanical strength of the device and the adhesiveness to the connector. Therefore, according to the optical fiber ribbon 1, the interval between the optical fiber strands 2 matches the fiber interval in the optical connector in advance, so that the optical fiber core 2 can be easily attached to the optical connector.

[0005]

When the optical fiber ribbon 1 shown in FIG. 6 is connected to an optical connector, the coating layer 3 of the optical fiber ribbon 1 is partially removed to remove the optical fiber 2.
It is necessary to perform so-called tapping, which exposes the end of the sheet. In general, tapping can be performed using various jigs.However, when a hot stripper is used as a tapping jig, for example, the optical fiber ribbon should be spaced so as not to contact the optical fiber. By passing between the two blades facing each other, the coating layer is removed.

However, in the optical fiber ribbon 1 shown in FIG. 6, since the thickness of the connecting portion 3a is thinner than the thickness of the wire portion 3b, if the optical fiber ribbon 1 is exposed using a hot stripper, As shown in 7, hot stripper blade 4
Contact only the wire portion 3b. Therefore, the coating material of the connecting portion 3 a remains and adheres to the drawn optical fiber 2, it becomes difficult to peel the coating layer 3 straight, and stress concentrates on the optical fiber 2. As a result, the optical fiber may be broken.

An object of the present invention is to solve the above-mentioned problems. That is, an object of the present invention is to provide a novel optical fiber ribbon which can easily, reliably and safely perform a tapping operation, and has a good connection with an optical connector, and a method of manufacturing the same. It is another object of the present invention to provide a die for manufacturing an optical tape having a structure that can be suitably used for manufacturing the above-described novel optical tape.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical tape core in which two optical fiber strands which are separated and arranged in parallel are coated with a resin and integrated, and the optical tape core is provided. The optical fiber is characterized in that the central part of the flat surface on both sides of the tape protrudes along the length direction, and the light that is resin-coated and integrated with two optical fiber strands that are separated and arranged in parallel. A method for manufacturing an optical fiber, wherein the optical fiber is coated with a resin so that a center portion of a flat surface on both sides of the optical fiber is projected along a length direction. Achieved by the method.

Another object of the present invention is to provide an optical fiber feeder, a discharge port, a coating passage connecting these, and a resin supply port communicating with the coating passage. The two optical fiber cores introduced in parallel in a state of being separated from the introduction port are collectively covered with the resin supplied from the resin supply port in the coating passage, and the optical tape core is delivered from the discharge port. An optical tape core, wherein a central part of a flat surface on both sides of an optical tape core wire sent from the discharge port is vertically expanded between the optical fiber strands. Achieved by manufacturing dies.

[0010]

FIG. 1 is a sectional view showing an embodiment of an optical fiber ribbon according to the present invention. As shown in FIG. 1, the optical fiber ribbon 1 is formed into a tape shape by integrating two optical fiber wires 2 with a coating layer 3 in a state of being separated from each other and arranged in parallel. It has a connecting portion 3a for connecting the optical fiber wires 2 and a wire portion 3b which is a portion covered by the optical fiber wire 2.

The connecting portion 3a has a thickness A in a direction perpendicular to a plane X passing through the center C of each section of the plurality of optical fiber strands 2. Further, the wire portion 3b includes a cross-sectional center C of the optical fiber wire 2 and has a thickness B in a direction perpendicular to the plane X. In the optical fiber ribbon 1 according to the present invention, the thickness A of the connecting portion 3a is equal to or greater than the thickness B of the wire portion 3b. That is, the connecting portion 3 between the optical fibers 2
The thickness A of “a” is larger than the thickness B of the wire portion 3b.

Therefore, when the optical fiber ribbon 1 shown in FIG. 1 is cut out using a hot stripper, FIG.
As is apparent from the above, in order for the blade 4 of the hot stripper to first come into contact with the connecting portion 3a protruding along the length direction and to uniformly peel off the covering material of the strand portion and the connecting portion, The resin of the coating layer does not remain on the optical fiber 2 at the time of tapping. Also, since the blade 4 is introduced into the optical fiber ribbon 1 from the connecting portion 3a having a small resistance, the blade 4
When stress is introduced, stress does not concentrate on the optical fiber 2, and therefore, there is no possibility that the optical fiber 2 is broken.

In the present invention, the thickness A of the connecting portion 3a>
If the relationship of the thickness B of the wire portion 3b is maintained,
The specific numerical values or ratios of the thickness A and the thickness B are appropriately adjusted depending on the use of the optical tape 1, the type of the resin constituting the coating layer 3, and the like. For example, in the optical tape core wire 1 used for applications such as indoor wiring, the thickness B of the wire portion 3b
Is usually 0.3 to 0.5 mm, and thickness A / thickness B
Is in the range of 1.1 to 2.0. Thickness A / Thickness B
If the ratio is less than 1.1, the connecting portion 3a remains stuck to the optical fiber 2 during tapping, or the stress is applied to the optical fiber 2 to cause breakage. It becomes difficult to put out. On the other hand, if the ratio of thickness A / thickness B is larger than 2.0, it is difficult to manufacture, for example, the film is inverted when it is wound up.

Although the type of the optical fiber 2 used in the present embodiment is not particularly limited, urethane acrylate and an optical fiber having an outer diameter of 125 μm may be used.
An optical fiber with an outer diameter of 250 μm having a two-layer coating layer formed by applying and curing an ultraviolet-curable resin such as epoxy acrylate or silicon acrylate over two layers is preferable.

In the optical fiber ribbon 1 shown in FIG. 1, the distance between the optical fiber wires 2 is set in advance so as to match the fiber distance in the optical connector to which the optical fiber ribbon 1 is connected. Usually, it is in the range of 0.2 to 0.8 mm. Specifically, for example, MT-RJ or small 2MT
When the connection with the optical connector is made as described above, the interval between the optical fibers 2 is set to 0.75 mm. In an optical fiber ribbon using three or more optical fiber strands, the intervals between the optical fiber strands are not necessarily uniform.

As described above, in the optical fiber ribbon 1 according to the present embodiment, since the distance between the optical fiber strands 2 matches the element distance of the optical connector in advance, the optical fiber ribbon is connected to the optical connector. This eliminates the need for extra work conventionally required.

The optical fiber ribbon 1 of the present embodiment is manufactured, for example, through the steps schematically shown in FIG. That is, first, the optical fiber 2 is sent out from each of the plurality of optical fiber sending sections 5, and these are arranged side by side in the alignment section 6 while being separated from each other.

Next, the two optical fiber strands 2 arranged in a plane are introduced into the coating die 7 in this state, and the inside thereof is coated with a liquid resin. Subsequently, the resin-coated optical fiber 2 is introduced into a curing device 8 where the liquid resin is cured to form a coating layer 3. Note that the outer diameter of the coating layer 3 of the optical tape core wire 1 that has exited the curing device 8 is monitored by an outer diameter measuring device 10,
The feed speed and the like of the optical fiber 2 are controlled by the measurement result of the outer diameter measuring device 10. Then, the optical fiber ribbon 1 thus manufactured is finally wound up by the winding device 9.

Here, a description will be given also with reference to FIG.
In the coating die 7 shown in FIG. 3, resin coating is performed such that the thickness A of the connecting portion 3a of the two optical fiber wires 2 is larger than the thickness B of the wire portion 3b. As the resin to be coated in the coating die 7, usually,
An ultraviolet-curable resin is used. In particular, an ultraviolet-curable acrylic resin such as urethane acrylate, epoxy acrylate, polybutadiene acrylate, silicone acrylate, or polyester acrylate is preferable, and the Young's modulus is 10 to 120 kg /. c
Those having about m ² are preferable. In addition, talc having an average particle size of 3 to 10 μm may be applied to these resins, or fine particles such as resin particles may be mixed in order to reduce the frictional resistance of the coating layer 3 and improve storage stability. .

FIG. 4 is a schematic side sectional view of the coating die 7. Coating die 7 in the present embodiment
Is provided with an inlet 7a and an outlet 7b of the optical fiber 2, a coating passage 7c connecting these, and a resin supply port 7d communicating with the coating passage 7c. The coating passage 7c has a resin supply port 7d. Is supplied under pressure. Therefore, the two optical fiber wires 2 introduced at a constant speed while being separated from each other and arranged in parallel from the inlet 7a are impregnated with the liquid resin in the coating passage 7c and are coated at once. Then, the optical fiber 2 covered with the resin in this manner is sent out from the discharge port 7b to the curing device 8.

Optical fiber 2 and coating die 7
In order to prevent damage to the optical fiber 2 and distortion of the coating layer 3 due to contact with the inlet 7a and the outlet 7b, at least the inner wall surfaces of the inlet 7a and the outlet 7b are surface-treated. Preferably, the roughness is suppressed to 6.0 μm or less. As the surface treatment, for example, precision grinding method,
Examples of the method include a mirror finishing method, an electrolytic polishing method, and a titanium plating.

In the present embodiment, the cross-sectional shape of the inlet 7a of the coating die 7 is flat so as not to hinder the introduction of the optical fiber 2, and the length of the tape in the side direction is light. The length in the thickness direction of the tape is set to be slightly larger than the parallel width of the optical fibers 2 and slightly larger than the outer diameter of the optical fiber 2.

On the other hand, a discharge port 7b opposed to the introduction port 7a
As shown in FIG. 5, the width H between the optical fiber strands 2 is smaller than the width H in the direction perpendicular to the plane X passing through the center of each cross section of the plurality of optical fiber strands 2 passing through the discharge port 7b. The shape is wider than the width W in the direction passing through the center of the cross section of the fiber strand 2. In other words, the discharge port 7b of the coating die 7 has an enlarged portion whose width is enlarged, and the two optical fiber strands 2 are arranged such that the gap between the fiber strands 2 coincides with the enlarged section. It passes through the discharge port 7b.

The cross-sectional shape of the discharge port 7b is such that the width H between the two optical fiber wires 2 passing through the discharge port 7b is larger than the width W of the portion facing the optical fiber wire 2. There is no particular limitation, and various cross-sectional shapes as shown in FIGS. 5 (a) to 5 (f) can be adopted. By using the coating die 7 having the discharge port 7b having such a cross-sectional shape, the thickness A of the connecting portion 3a of the plurality of optical fiber strands 2 as shown in FIG.
Can easily manufacture the optical tape 1 having a cross-sectional structure not less than the thickness B of the wire portion 3b. The ratio A / B of the thickness A and the thickness B in the optical fiber ribbon 1 thus manufactured can be controlled by the cross-sectional shape of the discharge port 7b. 7
It can also be controlled by the pressurized state of the liquid resin in c, the feeding speed of the optical fiber 2, the curing time of the liquid resin, and the like.

[0025]

EXAMPLE 1-6: An optical fiber ribbon was manufactured in accordance with the manufacturing process shown in FIG. 3 while using two optical fiber wires and changing the feed speed in a range of 100 to 600 m / min. did. An ultraviolet-curable liquid resin was used as the resin constituting the coating layer of the optical tape core wire, and the supply pressure was 1.5 kg / cm ² . As the coating die, a coating die having a discharge port having a cross-sectional shape shown in FIG. 5A was used, and the width H of the intermediate portion between the optical fiber wires of the discharge port and the portion facing the optical fiber wire were used. Are 0.50 mm and 0.45 m, respectively.
m. The distance from the discharge port to the curing device was set to 50 mm.

Comparative Example 1-6: An optical tape core was manufactured under the same conditions as in Example 1-6, except that a die having a discharge port having a sectional shape shown in FIG. 8 was used as a coating die.

With respect to the optical fiber ribbons obtained in Example 1-6 and Comparative Example 1-6, the ratio of the thickness A of the connecting portion to the thickness B of the wire portion was measured. Using a hot stripper (HJS-01), the optical fiber was spliced out, and the spouting property was evaluated. Table 1 shows the results.

[Table 1]

[0028]

In the optical fiber ribbon according to the present invention, the distance between the optical fibers is previously matched to the element distance of the optical connector or the like. The required extra work such as installation of a jumper cord is not required, and the installation work can be easily performed. Further, the optical fiber ribbon of the present invention can be used to peel the coating layer straight in a uniform state in an extraction step using a hot stripper or the like. Does not remain. Further, in the tapping step, the optical fiber is not damaged or broken. Therefore, the tapping operation can be performed easily and reliably.

Further, according to the manufacturing method of the present invention, it is possible to suitably manufacture the optical tape core wire having the above-described characteristics, and particularly, the manufacturing is performed using the optical tape core manufacturing die of the present invention. In this case, the optical fiber ribbon can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an embodiment of an optical tape core wire of the present invention.

FIG. 2 is a view showing a state in which the optical fiber ribbon of FIG.

FIG. 3 is a schematic view showing one example of a manufacturing process of the optical fiber ribbon of the present invention.

FIG. 4 is a schematic side sectional view of a coating die 7;

FIG. 5 is a diagram showing an example of a cross-sectional shape of a discharge port 7b of a coating die 7;

FIG. 6 is a cross-sectional view of a conventional optical tape.

FIG. 7 is a view showing a state in which the optical fiber ribbon shown in FIG. 6 is exposed.

FIG. 8 is a view showing the shape of a discharge port of a coating die used in a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical tape core wire 2 Optical fiber wire 3 Coating layer 4 Blade 5 Optical fiber sending part 6 Alignment part 7 Coating die 8 Curing device 9 Winding device 10 Outer diameter measuring device

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Shimomichi 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Keiji Ohashi 1-1-1, Kiba, Koto-ku, Tokyo Shareholders F-term in Fujikura (reference) 2H001 BB15 KK17 MM01

Claims (3)

[Claims] 1. An optical tape core obtained by integrally coating two optical fiber strands spaced apart from each other by resin coating, wherein the optical tape core has a central portion on both sides of the tape extending in a length direction. An optical tape core wire protruding along. 2. A method of manufacturing an optical fiber ribbon, wherein two optical fiber strands arranged in parallel at a distance are coated with a resin and integrated, wherein a central portion of a flat surface on both sides of the optical tape core is long. A method for producing an optical fiber ribbon, wherein the optical fiber ribbon is coated with a resin so as to protrude along the width direction. 3. An inlet and an outlet of the optical fiber, a coating passage connecting these, and a resin supply port communicating with the coating passage, wherein the resin supply port is spaced apart from the inlet and arranged in parallel. An optical tape core manufacturing die, in which the two introduced optical fiber wires are collectively coated with the resin supplied from the resin supply port in the coating passage and sent out from the discharge port, An optical tape core manufacturing die, wherein a central portion of a flat surface on both sides of an optical tape core wire delivered from an outlet is vertically enlarged between the optical fiber strands.