JPH058567Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Field of Application] The present invention relates to a connector for connecting flat multi-core optical fibers formed by arranging a plurality of optical fibers in parallel. [Prior Art] For example, as a conventional flat type connector for multi-core optical fibers of this type, the present applicant has proposed
There is a connector for multi-core optical fibers, which was previously filed in No. 62-198736. This multi-core optical fiber connector has an alignment member that has a plurality of grooves on one side of the inner tip of the ferrule, in which the optical fibers exposed by an appropriate length from the multi-core optical fiber are placed in parallel. and a buffer material placed on the optical fiber of the alignment member;
The apparatus includes a holding member disposed opposite to the alignment member and holding the optical fiber between the alignment member and the cushioning material. Each optical fiber of the multi-core optical fiber is placed in each groove of the alignment member, and the cushioning material is placed thereon and held by the pressing member. [Problem to be solved by the invention] The above-mentioned multi-core optical fiber connector can securely fix the optical fibers of the multi-core optical fiber, but the optical fibers and the alignment member may be damaged due to temperature changes. Due to the different expansion rates, if used for a long period of time, the tip of the optical fiber may protrude from the tip of the connector, which can cause problems in connecting the connector. Ta. The present invention has been developed in view of the above problems, and by interposing powder between the alignment member and the cushioning material to strengthen the holding force for the optical fibers, the optical fibers can be held securely and for a long period of time. It is an object of the present invention to provide a multi-core optical fiber connector that can be stably held over the entire length of the connector, can prevent the optical fiber from protruding from the connector tip, and can connect the connectors well. [Means for Solving the Problems] In order to achieve the above object, the present invention provides a multi-core optical fiber connector for connecting multi-core optical fibers formed by arranging a plurality of optical fibers in parallel. an alignment member comprising a plurality of grooves for placing the tip portions of each optical fiber exposed to an appropriate length in a parallel state; and an alignment member disposed on the optical fibers of the alignment member,
comprising a buffer material for sandwiching the optical fiber between the alignment member and a ferrule for disposing the alignment member and the buffer material at the distal end thereof and fixing the multi-core optical fiber core portion to the rear end thereof; Powder is interposed between the alignment member and the cushioning material to strengthen the holding force for the optical fiber. In addition, the present invention is a multi-core optical fiber connector that connects multi-core optical fibers made by arranging multiple optical fibers in parallel, in which the tips of each optical fiber with an appropriate length exposed are placed in parallel. an alignment member provided with a plurality of grooves to cause the optical fibers to be disposed between the alignment member and the buffer material; a buffer material placed on the optical fibers of the alignment member; a holding member for holding the optical fibers, and a ferrule for fixing the multi-core optical fibers to the rear ends of the holding members, and a ferrule for fixing the multi-core optical fibers to the rear ends thereof, and a powder for strengthening the holding force for the optical fibers. It was interposed between the alignment member and the buffer material. [Function] At the tip of the ferrule, the tip of each optical fiber, which is exposed to an appropriate length, is placed in parallel on the plurality of grooves of the alignment member, and a cushioning material or a cushioning material and a pressing member are placed on this. The tip of the optical fiber is held between the alignment member and the buffer material. Further, a multi-core optical fiber core portion is fixed to the rear end portion of the ferrule. The powder interposed between the alignment member and the buffer material strengthens the holding force for the optical fiber, and the optical fiber is securely held between the alignment member and the buffer material, and the tip of the connector This prevents the optical fiber from protruding from the outside. [Example] Hereinafter, the present invention will be specifically explained based on drawings showing examples thereof. Figure 1 is a partially cutaway front view of a multi-core optical fiber connector (hereinafter referred to as the connector) according to the present invention, Figure 2 is a reduced longitudinal sectional view thereof, and Figure 5 is an exploded perspective view thereof. be. The ferrule 1 has a cylindrical shape, and is provided with a flat hole 13b near the tip of the ferrule 1 along the axis of the ferrule 1, through which the multi-core optical fiber 2 is passed.
are in communication with an enlarged concave hole 13a formed at the tip of the ferrule 1 and an enlarged hole 13c formed at the rear end of the ferrule 1, respectively. The multi-core optical fiber 2 is, for example, a flat ribbon-like structure in which five optical fibers 21 each individually coated with a primary coating and a buffer layer are arranged in a layer and collectively coated with a secondary coating. The flat hole 1
The primary coating, buffer layer, and secondary coating are peeled off from the middle of 3b, and each exposed optical fiber 21 is inserted into the upper part of the enlarged recess 13a. Each optical fiber 21 has a plurality of fibers, in this case five V-shaped fibers, which are formed in parallel to the axial direction of the ferrule 1 on the upper surface of the rectangular plate-shaped alignment member 3 fitted in the enlarged recessed hole 13a. It is placed in the groove 31 of the mold, and each groove 3
1 are formed at substantially equal intervals to the mutual intervals of the respective optical fibers 21 in the multi-core optical fiber core wire 2 . Grooves 3 are provided on both sides of each groove 31 in the alignment member 3.
Similarly, V-shaped grooves 32, 32, which are larger than 1, are formed parallel to the groove 31, and each groove 32 is formed at a position facing each groove 32 on the upper surface of the enlarged recessed hole 13a. The groove 13d forms a guide pin insertion hole into which the guide pins 6, 6 can be inserted and removed. There is an enlarged concave hole 1 on the outer peripheral surface of the tip of the ferrule 1.
A communication hole 12 perpendicular to each optical fiber 21 placed in each groove 31 of the alignment member 3 in 3a.
is provided, and the diameter of the communicating hole 12 is equal to that of the groove 32.
The communicating hole 12 has a cylindrical shape having a diameter approximately equal to the diameter of the communicating hole 12,
Alternatively, a prismatic cushioning material 4 is fitted. The buffer material 4 is made of lead, indium, amorphous amorphous, annealed copper, etc., and the alignment member 3 is
A rectangular recess 4a having a width slightly wider than the width between the grooves 31 on both sides and a shallow depth is formed facing each groove 31. Powder 30 made of similar spherical small particles (particles of at least 0.5 μm or less) made of alumina ceramic or the like is interposed in this recess 4a. Then, by press-fitting the cushioning material 4 into the communication hole 12, the cushioning material 4 presses each optical fiber 21 through the powder 30 and clamps and fixes it between it and the groove 31 of the alignment member 3. . FIG. 3 is a partially cutaway front view of another embodiment of the optical fiber connector according to the present invention, and FIG.
The figure is a reduced longitudinal cross-sectional view of the ferrule 1, and a presser 5, which is a cylindrical or prismatic presser member, is fitted into the communication hole 12 at the tip of the ferrule 1 and has a diameter substantially equal to the diameter of the hole. A rectangular recess having a width wider than the width between the grooves 31 on both sides is formed on the lower surface of the pusher 5, and a buffer material 4 such as lead, indium, amorphous, or annealed copper is inserted into the recess. ing. This buffer material 4 includes each groove 3 of the alignment member 3.
1, a rectangular recess 4a having a width slightly wider than the width between the grooves 31 on both sides and a shallow depth is formed. In this recess 4a, similar spherical small particles (at least 0.5μ
Powder 30 consisting of particles of less than m is interposed. Then, when the pusher 5 is press-fitted into the communication hole 12, the buffer material 4 presses each optical fiber 21 and clamps and fixes it between it and the groove 31 of the alignment member 3. Here, the cushioning material 4 is prepared in advance so that it is filled in the recess of the pusher 5 and presses each optical fiber 21 through the powder 30 when the pusher 5 is completely press-fitted into the communication hole 12. It is desirable to set the size, thickness, etc. A positioning guide 11 is formed on the outer peripheral surface of the intermediate portion of the ferrule 1 in the axial direction. Also, a part of the rear end surface of ferrule 1 protrudes,
This protrusion serves as a twist locking key 15. 7 is a fitting member, the fitting member 7 has a truncated conical shape, and has a conical part 71 as a tapered part fitted in a conical hole part 81 of the ferrule 1 at the tip thereof,
It has a two-step enlarged diameter configuration including a cylindrical portion 72 as a cylindrical portion continuous to the large diameter side of this conical portion 71 and a flange portion 73 continuous to this cylindrical portion 72, The outer diameter of the cylindrical portion 72 is the same as that of the circular hole portion 82.
The outer diameter of the flange portion 73 is substantially equal to the outer diameter of the ferrule 1. Flange part 73
A hole is formed inside the cylindrical portion 72 at the axial center position, and the hole communicates with a slit 74 cut halfway through the cylindrical portion 72 from the tip of the female member 7 to include the axial center. ing. Furthermore, a portion of the flange portion 73 is cut out, and this cutout portion serves as a keyway 75 that fits into the twist locking key 15 of the ferrule 1. Reference numeral 10 denotes a cover tube that protects the inserted multi-core optical fiber, and the cover tube 10 is fitted into the bottom of the cup-shaped outer tube 9. Furthermore, 1 in the figure
Reference numeral 6 denotes a ring that is fitted onto the outer peripheral surface of the tip of the ferrule 1, and the fitting of the ring 16 allows pressure to be applied to the optical fiber at all times. Now, in the present connector configured as described above, first, a suitable length of the covering of the tip of the multi-core optical fiber is removed, and then the multi-core optical fiber with the exposed tip is inserted into the outer tube 9 and After passing it through the cover tube 10, it is inserted into the female member 7. Then, by fitting the fitting member 7 into the ferrule 1 in such a manner as to fit the anti-twist key 15 into the keyway 75, the multi-core optical fiber core wire is fitted and fixed, and then the ring 16 is fitted into the ferrule 1. After fitting it to the tip,
Each optical fiber 21 is exposed in advance from the multi-core optical fiber core 2 at the tip of the ferrule 1.
The powder 3 is placed between each groove 31 of the alignment member 3 and the recess 4a of the buffer material 4 by the alignment member 3 and the buffer material 4.
Align and clamp and fix with 0 interposed. Then, the optical fiber 21 protruding from the tip end surface of the ferrule 1 is finished flush with the tip end surface of the ferrule 1 by cutting, polishing, or the like. Then, as described above, each groove 31 of the alignment member 3
The holding force for the optical fiber 21 is strengthened by the powder 30 interposed between the alignment member 3 and the recess 4a of the cushioning material 4, and the optical fiber 21 is reliably held between the alignment member 3 and the cushioning material 4. , optical fiber 21
is prevented from protruding from the tip of the connector due to temperature changes. Next, the holding force of the powder 30 to the optical fiber 21 will be explained with respect to various materials and particle sizes, with experimental results shown in the graph of FIG. 6 and Table 1. In the graph of FIG. 6, the horizontal axis shows the particle size of the powder 30, and the vertical axis shows the holding force against the optical fiber 21. As for the powder materials, the white circles indicate alumina-based ceramics, the white triangles indicate zirconia-based ceramics, the black circles indicate metal powder, and the x marks indicate diamonds. Note that the shaded area is powder 3.
It shows the holding force when the optical fiber 21 is fixed with only the cushioning material 4 without using 0. In the experiment, the optical fiber 21 was placed on the alignment member 3, and the powder 30
The buffer material 4 was fixed by applying a pressure of 25 Kgf through the buffer material 4, and then the holding force of the optical fiber was measured while applying a pressure of 3 Kgf to the buffer material 4 again. As shown in this graph and Table 1, powder 30
The smaller the particle size of the particles, the stronger the holding force against the optical fiber 21 tends to be. Also,
Ceramic has shown good properties as a material for the powder 30. However, even with this ceramic, if the particle size becomes larger than 1 μm, the optical fiber
1, the optical fiber 21 may come out from between the alignment member 3 and the cushioning material 4, and there is a risk that the optical fiber 21 may break. In addition, if the powder 30 is made of metal, it can provide a certain degree of holding force for the optical fiber 21, but it does not fit into the grooves 31 of the alignment member 3 and easily peels off. is not suitable. Therefore, ceramic is suitable as the material for the powder 30, and the particle size of the powder must be 1 μm or less, preferably 0.5 μm or less. Further, with the powder 30 interposed between each groove 31 of the alignment member 3 and the recess 4a of the buffer material 4,
In order to hold and fix the optical fibers 21, the particle size of ceramic particles is 0.5 μm or less between each optical fiber 21 aligned and fitted into each groove 31 of the alignment member 3 and the recess 4a of the buffer material 4. When powder 30 of
is held between the alignment member 3 and the buffer material 4. Furthermore, it has been found that the best thickness of the powder 30 formed by press molding is about 0.1 to 0.3 mm for the reasons described below. Table 2 shows the powder 30 and the cushioning material 4 made of lead in the connector shown in FIG.
This figure shows the change in the amount of protrusion of the optical fiber 21 after a temperature test to confirm the fixing strength of the combination. In Experiment A, the cushioning material 4 was pressurized with the pusher 5 shown in FIG. 5, the thickness of the cushioning material 4 was 1 mm, the material of the powder 30 was alumina ceramic, and the particle size was 3 .mu.m. In addition, for experiment B, the thickness of the cushioning material 4 was set to 2 mm without the pusher 5,
The powder 30 was made of zirconium oxide and had a particle size of 0.2 μm. In addition, in both experiments A and B,
The cushioning material 4 was formed under pressure at 25 kgf, and the optical fiber core wire portion was fitted and fixed. The temperature change in the above temperature test is from -30℃ to 60℃
A heat cycle test was conducted in which the temperature was raised to 60°C and then lowered from 60°C to -30°C, and this was repeated for a total of 10 cycles. Further, the length from the connector at one end of the optical fiber core wire 2 to the connector at the other end was approximately 5 m. Further, the holding force of the powder 30 to the optical fiber 21 is within the range of 700 gf to 780 gf. As a result of the above-mentioned experiment, the amount of protrusion of the optical fiber 21 was approximately 10 μm, which was able to be suppressed approximately within the target standard value. Furthermore, as in Experiment A, when the pusher 5 is combined with the cushioning material 4, the strength of fixing the optical fiber 21 to the optical fiber 21 increases, and the amount of protrusion of the optical fiber 21 becomes smaller than 10 μm. However, just by press-fitting the buffer material into the body of the connector, a considerable amount of fixing strength to the optical fiber can be obtained, and the optical fiber 2
Since the protrusion amount of 1 can be suppressed to around 10 μm, by selecting the optimal powder, experiment B
It is also possible to use one in which the pusher 5 is not used, the buffer material is 2 mm, the powder material is zirconium oxide, and the particle size is 0.2 μm, as in the case of the example shown in FIG. The above experiment has shown that the method of fixing the optical fiber 21 between the buffer material 4 and the alignment member 3 by combining the buffer material 4 made of lead and the powder 30 is effective for holding and fixing the optical fiber 21. It was confirmed that this method can prevent the optical fiber 21 from protruding from the connector tip due to temperature changes. In this embodiment, a recess 4a is provided on the lower surface of the cushioning material 4, and powder 30 is interposed between the recess 4a and the optical fibers 21 aligned in the respective grooves 31 of the alignment member 3. However, the present invention is not limited to this, and for example, the powder 30
may be adhesively fixed to the lower surface of the cushioning material 4. Alternatively, with each optical fiber 21 placed in each groove 31 of the alignment member 3, powder 30 may be sprinkled on the placement portion to place the cushioning material 4 thereon. Further, when manufacturing the cushioning material 4, particles of the powder 30 are mixed in the material of the cushioning material 4 in advance, and then the particles of the powder 30 are mixed on the surface of the cushioning material 4. It may be made to exist.

【table】

【table】

[Effect of idea]

As described above, in the present invention, by interposing powder between the alignment member in which optical fibers are placed in parallel in a plurality of grooves and the buffer material, the powder can be used to protect the optical fibers from each other. The holding force can be strengthened, the optical fiber can be securely held between the alignment member and the buffer material, and the optical fiber can be prevented from protruding from the tip of the connector due to temperature changes, resulting in a good connector connection. It has the effect of being able to perform the following tasks.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway front view of a multi-core optical fiber connector according to the present invention, FIG. 2 is a reduced vertical sectional view thereof, and FIG. The figure is a partially cutaway front view of a multi-core optical fiber connector in another embodiment, FIG. 4 is a reduced longitudinal sectional view thereof, and FIG. 5 is an exploded perspective view of the multi-core optical fiber connector. FIG. 6 is a graph showing the experimental results of the holding force of the powder on the optical fiber. DESCRIPTION OF SYMBOLS 1... Ferrule, 2... Multi-core optical fiber core wire, 3... Aligning member, 4... Cushioning material, 5... Pusher, 21... Optical fiber, 30... Powder, 31
……groove.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a multi-core optical fiber connector for connecting multi-core optical fibers made by arranging multiple optical fibers in parallel, the tips of each optical fiber with an appropriate length exposed are connected in parallel. an alignment member comprising a plurality of grooves for placing the optical fibers in the alignment member; a buffer material disposed on the optical fibers of the alignment member and sandwiching the optical fibers between the alignment member and the buffer member; a ferrule for fixing the multi-core optical fiber core portion to the rear end thereof, and a powder for strengthening the holding force for the optical fibers to be placed between the alignment member and the buffer material. A connector for multi-core optical fiber, characterized in that it is interposed in a multi-core optical fiber. 2. In a multi-core optical fiber connector that connects multi-core optical fibers made by arranging multiple optical fibers in parallel, a plurality of grooves are provided in which the tips of each optical fiber exposed at an appropriate length are placed in parallel. an alignment member comprising: a buffer material placed on the optical fibers of the alignment member; and a presser disposed opposite the alignment member to sandwich the optical fibers between the alignment member and the buffer material. a member, and a ferrule disposed at the tips of the two members and fixing the multi-core optical fiber core portion to the rear end, and applying powder to the alignment member and the ferrule to strengthen the holding force for the optical fibers. A multi-core optical fiber connector characterized in that it is interposed between a buffer material and a buffer material.