JP2012155167A - Multi-fiber optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-fiber optical connector that enables a ferrule to be formed without use of core pins and also makes fibers accurately positioned.SOLUTION: In a multi-fiber optical connector 1, an optical fiber ribbon 3 is inserted into and fixed in a resin ferrule 5. In the ferrule 5, an oblong hole 7 is formed penetrating in the longitudinal direction thereof. The optical fiber ribbon 3 inserted into the ferrule 5 is constituted by a tape integrated part 9a in which a tape (and a coating) is coated and a coating removed part 9b in which, on the tip side thereof, the tape and the coating are removed and optical fibers 9 are exposed. In the tip end part of the oblong hole 7, a fiber-holding part 8 the diameter of which is reduced in the height direction thereof is formed. That is, the height of the fiber-holding part 8 is set to be slightly larger than the outer diameter of the optical fibers 9 within the range over which the optical fibers 9 can be inserted into.

Description

  The present invention relates to a multi-fiber optical connector in which a plurality of fiber core wires are arranged and inserted into a ferrule made of resin.

  2. Description of the Related Art Conventionally, a multi-fiber optical connector in which a plurality of optical fiber cores are aligned and inserted into a resin ferrule has been used.

  For example, an optical fiber connector formed by peeling off the coating on the tip of the optical fiber tape and inserting and fixing each optical fiber exposed from the end into a ferrule having holes formed at a predetermined pitch in advance. Yes (Patent Document 1).

JP 2002-46049 A

  Such a ferrule of a multi-fiber optical connector is usually formed by injection molding, but high positional accuracy of the optical fiber core wire is required. For this reason, a special high-hardness resin containing a glass filler or the like is used. Therefore, cost is high and moldability is bad.

  However, in order to form holes with a predetermined interval as in Patent Document 1, it is necessary to use a highly accurate core pin as a mold. However, in combination with the use of a special resin as described above, the core pin is broken. There is a fear. For this reason, especially in the case of a multi-core ferrule having several tens of cores or more, there is a possibility that the productivity of the ferrule is deteriorated and the cost is increased.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a multi-fiber optical connector in which a ferrule can be formed without using a core pin and a fiber is positioned with high accuracy.

  In order to achieve the above-mentioned object, the present invention is a multi-fiber optical connector, comprising a ferrule that holds an optical fiber, and a long hole formed in the ferrule, The fiber holding portion is formed so that the height of the elongated hole is reduced, and the tape integrated portion of the tape core wire is inserted from the end of the elongated hole to the fiber holding portion, and from the fiber holding portion to the ferrule Up to the end face, the tape removal of the tape core wire and the coating removal part from which the coating is removed are arranged, and in the fiber holding part, the vertical position of the coating removal part is regulated by the inner surface of the fiber holding part, The multi-fiber optical connector is characterized in that an adhesive is filled in a gap between the coating removal portions, and the coating removal portion is fixed to the elongated hole by the adhesive.

  It is preferable that a taper portion is formed on at least one inner surface behind the fiber holding portion so that the width of the elongated hole is reduced.

  The tapered portion is formed only on one inner surface of the elongated hole, the other inner surface is a linear portion, one side portion of the tape integrated portion is in contact with the linear portion, and the other side of the tape integrated portion is The tip of the side part may contact the taper part.

  The width of the elongated hole is larger than the width of the tape integrated portion, and the tape integrated portion may contact one inner surface of the elongated hole and may not contact the other inner surface.

  The fiber holding part may be provided with a groove shape corresponding to the outer shape of the coating removing part arranged in the fiber holding part. The length of the fiber holding part is preferably 0.3 to 0.5 mm.

  According to the present invention, since the elongated hole is formed in the ferrule, it is not necessary to use a core pin during manufacturing. Therefore, there is no fear of breakage of the core pin. For this reason, it is excellent in manufacturability and a multi-fiber optical connector can be manufactured at low cost.

  Further, the optical fiber core wire is positioned by the ferrule fiber holder only in the vertical direction, and the arrangement in the tape core wire is used as it is in the horizontal direction. For this reason, it is possible to obtain a multi-fiber optical connector having a simple structure while ensuring a certain degree of accuracy.

  Moreover, since the taper shape whose width is reduced in the tip direction of the long hole is formed, the insertion depth of the tape core wire can be made constant. For this reason, the length of the coating removal part can be made constant.

  At this time, a taper shape is provided only on one side surface, and the side surface of the tape core wire is disposed along the side surface (straight portion) opposite to the taper shape, so that the position of the tape core wire in the lateral direction with respect to the ferrule Can always be constant. For this reason, even if the tape core wire (optical fiber core wire) is manufactured to be biased to one side with respect to the ferrule, the connectors manufactured by the same method are connected to each other reliably because the shift amount is substantially the same. can do.

  Even when the taper shape is not provided, the same effect can be obtained by arranging the tape core wire so as to be in contact with one inner surface of the elongated hole. In any case, if a gap is formed between the tape core wire and the inner surface of the elongated hole, the insertion property of the tape core wire is improved and the positioning becomes easy.

  In addition, by forming the groove in the fiber holding portion, the position of the optical fiber core in the lateral direction can be more reliably regulated. In addition, if the length of the fiber holding portion is 0.3 to 0.5 mm, the positional deviation of the optical fiber core wire can be reduced.

  According to the present invention, the present invention has been made in view of such a problem, and provides a multi-fiber optical connector in which a ferrule can be formed without using a core pin and a fiber is positioned with high accuracy. be able to.

It is a figure which shows the multi-fiber optical connector 1, (a) is a perspective view, (b) is the sectional view on the AA line of (a). It is a figure which shows the fiber holding part vicinity, and is the C section enlarged view of FIG.1 (b). The front view of the multi-core optical connector 1. FIG. (A) is the BB sectional drawing of Fig.1 (a), (b) is the F section enlarged view of (a). (A) is a figure which shows the multi-fiber optical connector 1a, (b) is a figure which shows the multi-fiber optical connector 1b. The figure which shows the state which inserts the optical fiber 9 in the ferrule 5. FIG. The figure which shows the state which grind | polishes the front-end | tip of the ferrule 5. FIG. It is a figure which shows the alignment member 17, (a) is a perspective view, (b) is the J section expanded sectional view of (a). The figure which shows the state which attaches the alignment member 17 to a ferrule. The figure which shows the state which attached the alignment member 17a to the ferrule. (A) is a figure which shows the state which attached the alignment member 17b to the ferrule, (b) is the L section enlarged view of (a). (A) is a perspective view which shows the state which attaches the alignment member 30 to the ferrule 5, (b) is a front view. The front view which shows the other form of a multi-fiber optical connector.

  Hereinafter, a multi-fiber optical connector 1 according to an embodiment of the present invention will be described. Fig.1 (a) is a perspective view which shows the multi-fiber optical connector 1, FIG.1 (b) is the sectional view on the AA line of Fig.1 (a).

  The multi-fiber optical connector 1 is fixed by inserting a tape core wire 3 into a resin ferrule 5. The ferrule 5 is formed with a long hole 7 penetrating in the longitudinal direction. The long hole 7 may be of a size that allows insertion of the tape core wire 3. A guide hole 11 as a guide mechanism is provided on the end face of the ferrule 5. The position, size, shape and the like of the guide hole 11 are not limited to the illustrated example.

  As shown in FIG. 1 (b), the tape core wire 3 inserted into the ferrule 5 has a tape integrated portion 9a covered with the tape (and covering portion), and the tape and the covering are removed at the tip end side. It is comprised by the coating removal part 9b which the fiber 9 exposes. The optical fiber 9 has a diameter of 125 μm, for example, and is 250 μm at the covering portion. Accordingly, the optical fibers 9 are arranged at a pitch of approximately 250 μm in the coating removal portion 9b. In addition, about arrangement | positioning, the number, etc. of the optical fiber 9, it is not restricted to the illustrated example.

  FIG. 2 is an enlarged view of a portion C in FIG. A fiber holding portion 8 having a reduced diameter in the height direction is formed at the tip of the long hole 7. That is, the height of the fiber holding portion 8 is set to be slightly larger than the outer diameter of the optical fiber 9 within a range in which the optical fiber 9 can be inserted. Accordingly, the optical fiber 9 is positioned by the fiber holding portion 8 in the vertical direction (the direction of arrow D in the figure).

  The length (E in the figure) of the fiber holding portion 8 is preferably in the range of 0.3 to 0.5 mm. If the length of the fiber holding portion 8 is too short, the positioning accuracy in the height direction of the fiber 9 is deteriorated. Further, since the distance from the tape integrated portion 9a to the end surface increases as the length of the fiber holding portion 8 increases, the sheath removing portion 9b is laterally moved when it has a wrinkle in a direction away from the axial direction of the tape integrated portion 9a. The positional accuracy in the (optical fiber 9 arrangement direction) deteriorates.

  For example, even if the sheath removal portion 9b has an angular shift of 1 ° with respect to the axial direction of the tape integrated portion 9a, if the length of the fiber holding portion 8 is about 350 μm, the axial shift is 5 μm. Be suppressed within.

  FIG. 3 is a front view of the multi-fiber optical connector 1. As shown in FIG. 3, the optical fibers 9 are arranged in the fiber holding portion 8 at a pitch substantially equal to the arrangement pitch in the tape core wire 3.

  4A is a cross-sectional view taken along the line BB in FIG. 1A, and FIG. 4B is an enlarged view of a portion F in FIG. 4A. The width of the long hole 7 is formed larger than the width of the tape core wire 3. For this reason, the tape core wire 3 can be easily inserted into the long hole 7. On the other hand, the tape core wire 3 is fixed in close contact with one inner surface of the long hole 7. That is, a gap 6 is formed between the tape core wire 3 and the other inner surface of the long hole 7.

  By doing in this way, the optical fiber 9 is inserted straight with respect to the ferrule 5, and an axial shift is prevented. In this case, since the center of the ferrule 5 and the center of the tape core wire 3 are shifted, the optical fiber 9 is entirely arranged in one direction. However, this shift amount can be made constant by configuring all the connectors in the same manner. For this reason, if the connectors are connected to each other by reversing (reversing the front and back), the multi-fiber optical connectors are shifted in the same direction, so that they can be reliably connected.

  A multi-fiber optical connector 1a as shown in FIG. In the multi-fiber optical connector 1 a, tapered portions 15 that are reduced in diameter as the width of the long hole 7 of the ferrule 5 approaches the tip are formed on both inner side surfaces of the long hole 7. The tapered portion 15 is provided behind the fiber holding portion 8.

  By the taper part 15, the front end width of the long hole 7 is formed narrower than the width of the tape integrated part 9a. That is, the tape integrated portion 9a is inserted up to the taper portion 15 and is not inserted further. By doing in this way, it is prevented that a tape core wire is inserted excessively, and the length of a coating removal part can be made constant. In the multi-fiber optical connector 1a, the tape core wire 3 can be positioned in the center of the long hole 7 in the width direction by the tapered portions 15 on both sides.

  Moreover, it can also be set as the multi-fiber optical connector 1b as shown in FIG.5 (b). In the multi-fiber optical connector 1b, a tapered portion 15 whose diameter is reduced as the width of the long hole 7 of the ferrule 5 goes to the tip is formed only on one inner surface of the long hole 7. By the taper portion 15, the end width of the long hole 7 is formed to be narrower than the width of the tape integrated portion 9a. That is, the tape integrated portion 9a is inserted up to the taper portion 15 and is not inserted further. By doing in this way, it is prevented that a tape core wire is inserted excessively, and the length of a coating removal part can be made constant. In the multi-fiber optical connector 1b, the tape core wire 3 is brought into close contact with one inner side surface (straight portion) of the long hole 7 opposite to the side where the taper portion 15 is automatically formed by the taper portion 15. A gap is formed on the other side (taper portion 15 side).

  Next, a method for manufacturing the multi-fiber optical connector 1 will be described. First, as shown in FIG. 6 (a), the tape core wire 3 in which the tape and covering at the front end portion are removed in advance to form the covering removing portion 9b is inserted into the slot 7 from the rear end of the ferrule 5 (see FIG. 6). Middle arrow G direction). At this time, as shown in FIG. 6B, the optical fiber 9 is projected from the front of the long hole 7 by a predetermined length.

  Next, an adhesive is applied to the tip of the ferrule 5. At this time, first, the optical fiber 9 is made to protrude from the ferrule 5 longer than the specified length, an adhesive is applied, and the tape core wire 3 is pulled back from the ferrule 5 so that the adhesive adhered around the optical fiber 9 is adhered. The agent is drawn into the long hole 7. By doing in this way, the adhesive agent 13 can be apply | coated inside the long hole 7. FIG. The method for applying the adhesive 13 is not limited to the method described above. For example, an adhesive may be poured from a hole communicating with the long hole 7 formed in the ferrule 5, or the optical fiber 9 may be inserted after the adhesive 13 is applied in advance.

  After the adhesive 13 is cured, the optical fiber 9 protruding from the ferrule 5 and a part of the end face of the ferrule 5 are polished by the polishing surface 29 as shown in FIG. As described above, the multi-fiber optical connector 1 in which the optical fibers 9 are aligned in the long hole 7 can be obtained.

  According to the present invention, since a long hole is formed without forming a hole in the ferrule 5, it is not necessary to use a core pin when manufacturing the ferrule. Therefore, the ferrule manufacturability is excellent. Moreover, since the coating removal part 9b is formed and hold | maintained with the fiber holding part 8, the position of the up-down direction (D direction of FIG. 2) of the optical fiber core wire 9 can be regulated accurately. Moreover, if the length of the fiber holding part 8 is short, the position of the optical fiber core wire 9 in the horizontal direction (fiber arrangement direction in the tape core wire) can be aligned with high accuracy.

  Further, the optical fiber 9 from which the coating has been removed (coating removing portion 9 b) is located at the connector end, and the periphery of the optical fiber 9 is held by the adhesive 13 and the ferrule 5. For this reason, even when the end surface of the ferrule 5 is polished, the tip of the optical fiber core wire 9 is not damaged due to the influence of a soft covering portion or the like.

  Next, another embodiment will be described. 8A and 8B are views showing the alignment member 17, in which FIG. 8A is a perspective view, and FIG. 8B is an enlarged view of a portion F in FIG. 8A. In the manufacturing process described above, the optical fiber 9 may be positioned by the alignment member 17 when the adhesive 13 is cured after the adhesive 13 is applied.

  The alignment member 17 is, for example, a resin member, and a plurality of holes 19 are aligned and arranged at a predetermined pitch on one end surface. In addition, the hole 19 which is an alignment part may be a through-hole, and may be formed with predetermined depth. Guide pins 21 that are guide mechanisms are provided on both sides of the hole 19. The guide pin 21 is provided at a position and size corresponding to the guide hole 11 of the ferrule 5 described above. In addition, as the alignment member 17, the ferrule (patent document 1) etc. which were used conventionally can also be used as it is.

  As shown in FIG. 8B, the end portion of the hole 19 (the optical fiber insertion side to be described later) is formed with a tapered portion 23 whose diameter increases toward the end portion. The diameter of the hole 19 is set slightly larger than the diameter of the inserted optical fiber.

  FIG. 9 is a view showing a state in which the alignment member 17 is attached to the ferrule 5. As shown in FIG. 9A, the hole 19 side (guide pin 21 side) of the alignment member 17 is opposed to the ferrule 5, and the guide pin 21 is inserted into the guide hole 11 (in the direction of arrow K in the figure). At this time, by setting the length of the guide pin 21 to be longer than the protruding length of the optical fiber 9, first, the guide pin 21 is inserted into the guide hole 11 and the position of the alignment member 17 and the ferrule 5 is regulated. be able to. From this state, the tip of the optical fiber 9 can be inserted into the hole 19 by further inserting the alignment member 17 to the ferrule side.

  At this time, it is desirable that the end surface of the ferrule 5 is directed upward and the alignment member 17 is opposed to the ferrule 5 from above. This is to prevent the adhesive 13 from flowing in the direction of the alignment member 17. Alternatively, the adhesive 13 may be applied with the tip of the optical fiber 9 inserted into the hole 19. In this case, the adhesive is prevented from adhering to the alignment member 17. Further, the alignment member 17 itself may be made of a fluororesin or the like so that the adhesive does not adhere.

  As shown in FIG. 9B, when the optical fibers 9 are all inserted into the corresponding holes 19, the positions of the respective optical fibers 9 are regulated by the positions of the holes 19. That is, the holes 19 can be aligned with substantially the same accuracy. In this state, the adhesive 13 is cured to fix the optical fiber 9 to the ferrule 5 (the inner surface of the long hole 7). Thereafter, the alignment member 17 may be removed and polished as shown in FIG.

  The guide mechanism for positioning the alignment member and the ferrule is not limited to the guide pin and the guide hole. For example, as shown in FIG. 10, a tapered guide portion 21 a may be formed on the side facing the ferrule 5. By doing so, the alignment member 17a can be positioned with respect to the ferrule 5. That is, any guide mechanism may be used as long as the mechanism can perform positioning with respect to the ferrule 5.

  Also, an alignment member 17b as shown in FIG. 11 can be used. FIG. 11A is a view showing a state in which the alignment member 17b is attached to the ferrule 5, and FIG. 11B is an enlarged view of a portion L in FIG. 11A. A convex step 25 (or protrusion) is formed on a part of the surface facing the ferrule 5 on the alignment member 17b. That is, the gap 27 is formed between the opposing surfaces of the ferrule 5 and the alignment member 17b in a state of being attached to the ferrule 5.

  As shown in FIG. 11B, the adhesive 13 adheres to the end face of the ferrule 5, but by forming the gap 27, it is possible to prevent the adhesive 13 from adhering to the alignment member 17b. Further, since the tapered portion 23 is formed on the end surface of the hole 19, it is possible to reliably prevent the adhesive 13 that is raised on the surface of the optical fiber 9 due to surface tension from adhering to the alignment member 17b. .

  An alignment member 30 as shown in FIG. 12 can also be used. As shown in FIG. 12A, the alignment member 30 is provided with a plurality of grooves 31 corresponding to the number of optical fibers 9. The individual widths of the grooves 31 that are the alignment portions correspond to the diameter of the optical fiber 9. Guide grooves 35 as guide mechanisms are provided on both sides of the plurality of grooves 31. The guide groove 35 corresponds to the guide pin 33 inserted into the guide hole of the ferrule 5a. In this embodiment, an example in which the optical fibers 9 are provided in two stages is shown, but the present invention is not limited to this. Similarly, in the above-described embodiments, the optical fibers 9 may be formed in a plurality of stages.

  First, as shown in FIG. 12A, the alignment member 30 is attached to the ferrule 5a (in the direction of arrow M in the figure). At this time, a taper portion (not shown) is formed at the upper end portion of the groove 31 (the same taper portion as the taper portion 23 in FIG. 8B). In this case as well, as described above, it is desirable to attach the alignment member 30 with the end face of the ferrule 5a facing upward.

  FIG. 12B is a front view of a state in which the optical fiber 9 is inserted into the groove 31 of the alignment member 30. As shown in FIG. 12B, the optical fibers 9 are inserted into the respective grooves 31, thereby being aligned at a pitch corresponding to the pitch of the grooves 31. That is, the arrangement direction of the optical fibers 9 in the tape core wire 3 (the direction of the arrow N in the figure) is positioned by the groove 31.

  By using the alignment member as described above, the alignment accuracy of the optical fiber 9 is regulated by the alignment member. For this reason, the ferrule 5 does not require high accuracy. For this reason, it is not necessary to use special resin. Further, since the optical fibers are positioned by the alignment member, they can be aligned with extremely high accuracy. Moreover, since the taper part 23 is formed in the edge part of the hole 19 of an alignment member, the insertion property of the optical fiber 9 is good, and it can also prevent that the adhesive agent 13 adheres to an alignment member.

  Further, in the alignment member 17 b, the gap 27 can be formed between the end surface of the ferrule 5 by providing the step 25 on the end surface of the alignment member. For this reason, it can prevent that the adhesive agent 13 adheres to an alignment member.

  Further, since the alignment member 30 has a plurality of grooves 31, the same alignment member can be used even when aligning a plurality of stages of optical fibers.

  As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

  For example, in order to quickly cure the adhesive 13 with the optical fiber 9 inserted into the alignment member, a heater, an ultraviolet irradiation mechanism, or the like can be provided on the surface of the alignment member facing the ferrule. That is, an adhesive curing mechanism may be provided on the alignment member side in accordance with the adhesive to be used.

  Further, as shown in FIG. 13, a groove 10 may be formed in the fiber holding portion 8 of the ferrule 5. By making the groove 10 correspond to the outer diameter of the optical fiber 9, it is possible to suppress the lateral displacement of the optical fiber 9, so that the optical fiber can be accurately arranged without using an alignment member. Even in such a configuration, it is not necessary to use a core pin in the mold, so there is an advantage in manufacturability and price of the ferrule.

DESCRIPTION OF SYMBOLS 1, 1a ......... Multi-fiber optical connector 3 ......... Tape core wire 5 ......... Ferrule 6 ......... Gap 7 ...... Elongation hole 8 ...... Fiber holding part 9 ......... Optical fiber 9a ......... Tape integrated portion 9b ......... Coating removal portion 10 ......... Groove 11 ......... Guide hole 13 ......... Adhesive 15 ......... Tapered portion 17, 17a, 17b, 30 ......... Alignment member 19 ......... Hole 21 ......... Guide pin 23 ......... Tapered portion 25 ......... Step 27 ......... Gap 29 ......... Polished surface 31 ......... Groove 33 ......... Guide pin 35 ......... Guide groove

Claims (6)

A multi-fiber optical connector,
A ferrule holding an optical fiber;
A slot formed in the ferrule;
Comprising
A fiber holding portion is formed at the tip of the elongated hole so that the height of the elongated hole is reduced,
A tape removing portion in which the tape integrated portion of the tape core wire is inserted from the end of the elongated hole to the fiber holding portion, and the tape and the coating of the tape core wire are removed from the fiber holding portion to the end surface of the ferrule. Is placed,
In the fiber holding portion, the vertical position of the coating removal portion is regulated by the inner surface of the fiber holding portion, a gap between the coating removal portions is filled with an adhesive, and the coating removal portion is A multi-fiber optical connector, which is fixed to the elongated hole by an adhesive.   2. The multi-fiber optical connector according to claim 1, wherein a tapered portion is formed on at least one inner surface behind the fiber holding portion so that the width of the elongated hole is reduced.   The tapered portion is formed only on one inner surface of the elongated hole, the other inner surface is a linear portion, one side portion of the tape integrated portion is in contact with the linear portion, and the other side of the tape integrated portion is The multi-fiber optical connector according to claim 2, wherein a distal end of the side portion is in contact with the tapered portion.   The width of the long hole is larger than the width of the tape integrated part, and the tape integrated part contacts one inner surface of the elongated hole and does not contact the other inner surface. The multi-fiber optical connector according to 1.   5. The multi-fiber optical connector according to claim 1, wherein the fiber holding portion is provided with a groove shape corresponding to an outer shape of a sheath removing portion disposed in the fiber holding portion. .   The multi-fiber optical connector according to any one of claims 1 to 5, wherein a length of the fiber holding portion is 0.3 to 0.5 mm.

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