JP2015163932A - Optical fiber fixing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical fiber fixing structure capable of ensuring that an end portion of an optical fiber is fixed at a predetermined end surface position within a connector.SOLUTION: A sleep chuck 15a including a slot extending from a tip end in a length direction is configured to abut on a surface of a tapered hole portion 11c of a through-hole 11 of a connector 10 and to be caulked in a state of inserting an optical fiber core wire 5 into the sleeve chuck 15a, thereby holding the optical fiber core wire 5 by a coating layer 4 and fixing the optical fiber core wire 5 within the through-hole 11 of the connector 10, and the sleep chuck 15a includes a rear end straight portion 16a provided to be engaged with a large-diameter hole portion 11a of the through-hole 11, a tip end straight portion 17a provided to be engaged with a small-diameter hole portion 11b, and a tapered portion 18a provided to be engaged with the tapered hole portion 11c.

Description

  The present invention relates to an optical fiber fixing structure, and more particularly to a structure for fixing an end portion of an optical fiber inside a connector.

  For example, a connector for connecting to a receptacle provided in an incident optical system or an outgoing optical system is fixed to the end of the optical fiber.

  For example, Patent Document 1 discloses a laser processing optical fiber connector that fixes an optical fiber to a ferrule by chucking the optical fiber to a ferrule via a sleeve.

JP 2001-318271 A

  By the way, in the connector in which the end portion of the optical fiber is fixed inside the cylindrical connector, the end face of the optical fiber is predetermined inside the connector in order to optically couple with the incident optical system, the outgoing optical system, and the like. It is important to be surely placed in the position. However, for example, when the end of the optical fiber is fixed inside the connector by caulking the sleeve chuck interposed between the connector and the optical fiber, the optical fiber is connected to the connector when caulking the sleeve chuck. There is room for improvement because it may move inside.

  The present invention has been made in view of such a point, and an object of the present invention is to securely fix the end portion of the optical fiber at the position of a predetermined end surface inside the connector.

  In order to achieve the above object, the present invention provides a straight tip that a sleeve chuck that holds an optical fiber core wire with a coating layer and is fixed inside a through hole of a connector engages with a small diameter hole of the through hole of the connector. A part is provided.

  Specifically, in the optical fiber fixing structure according to the present invention, the end portion of the optical fiber core wire having the coating layer provided on the outer periphery is fixed to the inside of the through hole of the connector in which the through hole is formed via the sleeve chuck. In the optical fiber fixing structure, the through hole of the connector is formed to have a relatively large diameter and is relatively small with a large diameter hole portion that accommodates a rear end portion of the end portion of the optical fiber core wire. A small-diameter hole that is formed in a diameter and accommodates the tip of the end of the optical fiber core wire, and is provided between the large-diameter hole and the small-diameter hole, and from the large-diameter hole to the small-diameter hole The sleeve chuck has a slit formed so as to extend in the length direction from the tip, and the optical fiber core wire is inserted through the sleeve chuck. To tighten against the surface of the taper hole. The optical fiber core wire is held by the coating layer and is fixed inside the through hole of the connector, and the rear end provided to engage with the large-diameter hole portion A straight portion, a tip straight portion provided to engage with the small-diameter hole portion, and a tapered portion provided to engage with the tapered hole portion.

  According to said structure, the sleeve chuck in which the slit extended in the length direction from the front-end | tip is equipped with the front end straight part, taper part, and back end straight part which were provided in order toward the rear end from the front-end | tip. . Here, since the rear straight portion is provided so as to be engaged with the large-diameter hole portion of the through hole of the connector, the sleeve chuck with the optical fiber core wire inserted in the through hole of the connector. Can be slid smoothly. In addition, since the taper portion is provided so as to engage with the taper hole portion of the through hole of the connector, the taper portion comes into contact with the surface of the taper hole portion and is crimped, so that the light is generated inside the through hole of the connector. The sleeve chuck can be fixed in a state where the fiber core wire is held by the coating layer. Furthermore, since the straight end portion is provided so as to engage with the small-diameter hole portion of the through hole of the connector, the optical fiber core wire can be held by the coating layer in conjunction with the tapered portion. As a result, the optical fiber core wire is held not only at the taper portion of the sleeve chuck but also at the straight end portion of the sleeve chuck, so that the end portion of the optical fiber core wire is securely fixed inside the through hole of the connector, and the optical fiber The position of the end face of the fiber core wire is fixed. Therefore, the end of the optical fiber can be reliably fixed at the position of the predetermined end surface inside the connector.

  The surface which contacts the said coating layer of the said front end straight part and a taper part may be threaded.

  According to the above configuration, the surface that contacts the coating layer of the optical fiber core wire is threaded at the tip straight portion and the taper portion of the sleeve chuck, so that the optical fiber core wire is fixed inside the through hole of the connector. The force can be improved by the thread.

  The sleeve chuck may be made of an elastic metal.

  According to the above configuration, since the sleeve chuck is made of an elastic metal such as phosphor bronze, the fixing force of the optical fiber core wire in the through hole of the connector is improved by the elastic force of the sleeve chuck. Can do.

  In the small diameter hole portion, the optical fiber core wire protruding from the sleeve chuck may have the coating layer removed and the side surface of the optical fiber exposed.

  According to said structure, in the small diameter hole part of the through-hole of a connector, the coating layer of the optical fiber core wire is removed and the side surface of an optical fiber is exposed. Therefore, for example, even if the laser light incident from the end face of the optical fiber enters the space outside the optical fiber in the small-diameter hole portion of the connector due to misalignment of the laser light or the thermal lens effect, the laser light However, it is difficult to directly enter the coating layer of the optical fiber core wire, so that burning of the coating layer due to direct incidence of laser light can be suppressed.

  On the distal end side of the distal straight portion of the sleeve chuck engaged with the small-diameter hole, the optical fiber core wire may have the coating layer removed and the side surface of the optical fiber exposed.

  According to the above configuration, the coating layer of the optical fiber core wire is removed and the side surface of the optical fiber is exposed at the distal end side of the distal straight portion of the sleeve chuck engaged with the small diameter hole portion of the through hole of the connector. Yes. Therefore, for example, of the laser light incident from the end face of the optical fiber due to misalignment of the laser light or the thermal lens effect, the laser light propagating through the cladding of the optical fiber, that is, the cladding mode light is, for example, a mode. After being radiated to the outside via a stripper, etc., even if it propagates through the small-diameter hole of the connector and enters the front end side of the straight end of the sleeve chuck, the clad mode light is applied to the coating layer of the optical fiber core wire. Hard to reach. Thereby, the burning of the coating layer by clad mode light can be suppressed.

  Here, when the sleeve chuck is formed of a metal such as oxygen-free copper having higher thermal conductivity than phosphorous bronze having elasticity, it effectively absorbs the heat generated in the sleeve chuck by the incidence of laser light. And since the heat can be discharged | emitted out of a connector, the burning of the coating layer by clad mode light can be suppressed further. Furthermore, when the surface of the sleeve chuck is gold-plated, the heat generated by the sleeve chuck due to the incidence of laser light can be absorbed more effectively, and the heat can be discharged out of the connector. Further, it is possible to further suppress the burning of the coating layer due to the clad mode light.

  In addition, even if the coating layer of the optical fiber core wire is removed on the tip side of the tip straight portion of the sleeve chuck, since the coating layer of the optical fiber core wire remains on the rear end side of the tip straight portion, The optical fiber core wire can be sufficiently held by the coating layer by the rear end portion of the straight end portion of the sleeve chuck.

  A mode stripper may be formed on the side surface of the optical fiber from which the coating layer has been removed.

  According to said structure, the mode stripper is formed in the side surface of the optical fiber from which the coating layer of the optical fiber core wire was removed. Therefore, for example, even if clad mode light propagating through the clad of the optical fiber is emitted through the mode stripper, the emitted clad mode light is difficult to reach the coating layer of the optical fiber core wire. Burnout of the coating layer can be effectively suppressed.

  According to the present invention, the sleeve chuck that holds the optical fiber core wire with the covering layer and is fixed inside the through hole of the connector includes the straight end portion that engages with the small diameter hole portion of the through hole of the connector. In the connector, the end of the optical fiber can be securely fixed at the position of the predetermined end face.

1 is a longitudinal sectional view of an optical fiber fixing structure according to Embodiment 1. FIG. It is a side view of the sleeve chuck which comprises an optical fiber fixing structure. It is a front view of a sleeve chuck. It is a rear view of a sleeve chuck. It is a perspective view of the optical fiber core wire which comprises an optical fiber fixing structure. 6 is a longitudinal sectional view of an optical fiber fixing structure according to Embodiment 2. FIG. 6 is a longitudinal sectional view of an optical fiber fixing structure according to Embodiment 3. FIG. It is a longitudinal cross-sectional view of the optical fiber fixing structure of a comparative example. It is a side view of the sleeve chuck of a comparative example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments.

Embodiment 1 of the Invention
1 to 5 show Embodiment 1 of an optical fiber fixing structure according to the present invention. Specifically, FIG. 1 is a longitudinal sectional view of an optical fiber fixing structure 30a of the present embodiment. FIG. 2 is a side view of the sleeve chuck 15a constituting the optical fiber fixing structure 30a. FIG. 3 is a front view of the sleeve chuck 15a as viewed from the front end side. FIG. 4 is a rear view of the sleeve chuck 15a as viewed from the rear end side. FIG. 5 is a perspective view of the optical fiber core wire 5 constituting the optical fiber fixing structure 30a. 1 is a cross-sectional view of an optical fiber fixing structure 30a provided with a sleeve chuck 15a along the AA cross section in FIG.

  As shown in FIG. 1, the optical fiber fixing structure 30a includes a connector 10 in which a through hole 11 is formed, an optical fiber core wire 5 fixed inside the through hole 11 via a sleeve chuck 15a, and the through hole 11. And a chuck screw 20 for holding the optical fiber core wire 5 and the sleeve chuck 15a inside the through-hole 11 while holding the sleeve chuck 15a from the rear (right side in the figure).

  As shown in FIGS. 1 and 5, the optical fiber core wire 5 includes, for example, an optical fiber 3 for transmitting laser light and a coating layer 4 provided to cover the optical fiber 3. .

  As shown in FIG. 5, the optical fiber 3 includes a core 1 and a clad 2 provided so as to cover the core 1. Here, the core 1 is made of, for example, quartz, and has a refractive index (for example, 1.457) of quartz alone. The clad 2 is formed of, for example, quartz doped with fluorine, boron, or the like, and has a refractive index lower than the refractive index of the core 1 (for example, 1.443).

  As shown in FIG. 5, the covering layer 4 includes a buffer layer 4 a and a jacket layer 4 b provided so as to cover the buffer layer 4 a. Here, the buffer layer 4a is formed of, for example, a silicone resin. The jacket layer 4b is made of, for example, nylon resin.

  The connector 10 is formed in a substantially cylindrical shape with a metal such as stainless steel. And as shown in FIG. 1, the through-hole 11 of the hollow part of the connector 10 has the large diameter hole part 11a formed in the relatively large diameter, and the small diameter hole part 11b formed in the relatively small diameter. And a tapered hole portion 11c provided between the large-diameter hole portion 11a and the small-diameter hole portion 11b and formed to reduce the diameter from the large-diameter hole portion 11a toward the small-diameter hole portion 11b. Here, as shown in FIG. 1, the large-diameter hole portion 11 a and the small-diameter hole portion 11 b are provided so as to accommodate the rear end portion and the front end portion of the end portion of the optical fiber core wire 5, respectively. In the optical fiber fixing structure 30a, as shown in FIG. 1, the coating layer 4 of the optical fiber core wire 5 protruding from the sleeve chuck 15a is removed in the small diameter hole portion 11b of the connector 10 so that the side surface of the optical fiber 3 is Exposed. A female screw for screwing the chuck screw 20 is formed on the surface of the rear end side of the large diameter hole portion 11a.

  The sleeve chuck 15a is formed in a substantially cylindrical shape by an elastic metal such as free-cutting phosphor bronze. Further, as shown in FIGS. 2 to 4, four slits 19 are formed at the distal end portion of the sleeve chuck 15 a at intervals of 90 degrees in the circumferential direction so as to extend in the length direction from the distal end. The sleeve chuck 15a holds the optical fiber core wire 5 with the coating layer 4 by crimping the sleeve chuck 15a with its tip portion in contact with the surface of the tapered hole portion 11c with the optical fiber core wire 5 inserted. The connector 10 is configured to be fixed inside the through hole 11 of the connector 10.

  Further, as shown in FIGS. 1 and 2, the sleeve chuck 15a is provided so as to engage with the rear straight portion 16a provided to engage with the large-diameter hole portion 11a and the small-diameter hole portion 11b. The tip straight part 17a and the taper part 18a provided to engage with the taper hole part 11c are provided. Here, the tip straight part 17a and the taper part 18a are separated into four by four slits 19, respectively. Moreover, the surface which contacts the coating layer 4 of the front straight part 17a and the taper part 18a is threaded.

  The chuck screw 20 is formed in a substantially cylindrical shape by a metal such as stainless steel, for example. Here, on the outer peripheral surface of the chuck screw 20, a male screw that is screwed into a female screw formed on the surface on the rear end side of the large-diameter hole portion 11 a is formed.

  In the optical fiber fixing structure 30a configured as described above, first, the sleeve chuck 15a and the chuck screw 20 are sequentially inserted into the through hole 11 of the connector 10 from the rear end side, and then the end portion of the optical fiber core wire 5 is covered. After removing the layer 4, the optical fiber core wire 5 is inserted into the sleeve chuck 15 a and the chuck screw 20 from the side where the coating layer 4 is removed, and the optical fiber core wire 5 is held by the coating layer 4. In order to fix the sleeve chuck 15a in the state, it can be manufactured by tightening the chuck screw 20 with a torque driver (torque wrench) and crimping the tip portion of the sleeve chuck 15a.

  Here, when manufacturing the optical fiber fixing structure 30a, the coating layer 4 of the optical fiber core wire 5 is not only the tapered portion 18a of the sleeve chuck 15a but also the straight end of the sleeve chuck 15a by caulking the tip portion of the sleeve chuck 15a. Since the portion 17a is also held, the end face of the optical fiber 3 of the optical fiber core wire 5 is difficult to protrude forward (left side in FIG. 1).

  On the other hand, the optical fiber fixing structure 130 of the comparative example is as follows. Here, FIG. 8 is a view corresponding to FIG. 1 of the optical fiber fixing structure 130 of the comparative example. FIG. 9 is a view corresponding to FIG. 2 of the sleeve chuck 115 constituting the optical fiber fixing structure 130.

  As shown in FIG. 8, the optical fiber fixing structure 130 is substantially the same as the optical fiber fixing structure 30a except that the sleeve chuck 15a of the optical fiber fixing structure 30a is replaced with a sleeve chuck 115. It has become. Here, the sleeve chuck 115 is formed in a substantially cylindrical shape by an elastic metal such as free-cutting phosphor bronze. Further, as shown in FIG. 9, four slits 119 are formed at the distal end portion of the sleeve chuck 115 at intervals of 90 degrees in the circumferential direction so as to extend in the length direction from the distal end. The sleeve chuck 115 holds the optical fiber core wire 5 with the coating layer 4 when the optical fiber core wire 5 is inserted and the tip portion of the sleeve chuck 115 abuts against the surface of the tapered hole portion 11c and is crimped. The connector 10 is configured to be fixed inside the through hole 11 of the connector 10. Further, as shown in FIGS. 8 and 9, the sleeve chuck 115 is provided so as to engage with the rear straight end portion 116 provided to engage with the large-diameter hole portion 11a and the tapered hole portion 11c. And a tapered portion 118. The tapered portion 118 is divided into four by four slits 119. Moreover, the surface which contacts the coating layer 4 of the taper part 118 is threaded. The material of the sleeve chuck 115 is the same as that of the sleeve chuck 15a, and the sizes of the rear end straight portion 116 and the taper portion 118 are the same as those of the rear end straight portion 16a and the taper portion 18a of the sleeve chuck 15a. That is, the sleeve chuck 115 has a configuration in which the tip straight portion 17a of the sleeve chuck 15a is omitted.

  Here, when the optical fiber fixing structure 130 is manufactured, the coating layer 4 of the optical fiber core wire 5 is held only by the tapered portion 118 of the sleeve chuck 115 by crimping the tip portion of the sleeve chuck 115. Therefore, due to the tightening of the chuck screw 20, the end face of the optical fiber 3 of the optical fiber core wire 5 tends to protrude forward (left side in FIG. 8).

  As described above, according to the optical fiber fixing structure 30a of this embodiment, the sleeve chuck 15a in which the slit 19 extending in the length direction from the tip is formed, the tip provided in order from the tip to the rear end. The straight part 17a, the taper part 18a, and the rear-end straight part 16a are provided. Here, since the rear straight portion 16 a is provided so as to engage with the large-diameter hole portion 11 a of the through hole 11 of the connector 10, the optical fiber core wire 5 is placed inside the through hole 11 of the connector 10. The sleeve chuck 15a can be smoothly slid in the inserted state. Further, since the taper portion 18a is provided so as to engage with the taper hole portion 11c of the through hole 11 of the connector 10, the taper portion 18a penetrates the connector 10 by being abutted against the surface of the taper hole portion 11c and crimped. Inside the hole 11, the sleeve chuck 15 a can be fixed in a state where the optical fiber core wire 5 is held by the coating layer 4. Further, since the straight end portion 17a is provided so as to engage with the small diameter hole portion 11b of the through hole 11 of the connector 10, the optical fiber core wire 5 is held by the coating layer 4 in conjunction with the tapered portion 18a. can do. As a result, the optical fiber core wire 5 is held not only by the taper portion 18a of the sleeve chuck 15a but also by the straight end portion 17a, so that the end portion of the optical fiber core wire 5 is surely secured inside the through hole 11 of the connector 10. And the position of the end face of the optical fiber core wire 5 (optical fiber 3) are fixed. Therefore, the end of the optical fiber 3 can be reliably fixed at the position of the predetermined end surface inside the connector 10.

  Further, according to the optical fiber fixing structure 30a of the present embodiment, the surface of the tip end straight portion 17a and the tapered portion 18a of the sleeve chuck 15a that contacts the coating layer 4 of the optical fiber core wire 5 is threaded. The fixing force of the optical fiber core wire 5 inside the through hole 11 of the connector 10 can be improved by the screw thread.

  Further, according to the optical fiber fixing structure 30a of the present embodiment, since the sleeve chuck 15a is made of an elastic metal, the optical fiber core in the through hole 11 of the connector 10 is formed by the elastic force of the sleeve chuck 15a. The fixing force of the line 5 can be improved.

  Further, according to the optical fiber fixing structure 30a of the present embodiment, the coating layer 4 of the optical fiber core wire 5 is removed and the side surface of the optical fiber 3 is exposed in the small diameter hole portion 11b of the through hole 11 of the connector 10. Yes. Therefore, for example, the laser light incident from the end face of the optical fiber 3 is incident on the space outside the optical fiber 3 in the small-diameter hole portion 11b of the connector 10 due to the misalignment of the laser light or the thermal lens effect. However, since the laser beam is difficult to directly enter the coating layer 4 of the optical fiber core wire 5, it is possible to suppress burning of the coating layer 4 due to direct incidence of the laser beam.

<< Embodiment 2 of the Invention >>
FIG. 6 is a longitudinal sectional view of the optical fiber fixing structure 30b of the present embodiment. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same part as FIGS. 1-5, and the detailed description is abbreviate | omitted.

  In the first embodiment, the optical fiber fixing structure 30a in which the coating layer 4 of the optical fiber core wire 5 is formed up to the distal end surface of the distal straight portion 17a is exemplified. However, in the present embodiment, the coating layer of the optical fiber core wire 5 is illustrated. The optical fiber fixing structure 30b formed so that 4 may recede from the front end surface of the front end straight portion 17b is illustrated.

  As shown in FIG. 6, the optical fiber fixing structure 30 b includes a connector 10 in which the through hole 11 is formed, an optical fiber core wire 5 fixed inside the through hole 11 via a sleeve chuck 15 b, and the through hole 11. And a chuck screw 20 for holding the optical fiber core wire 5 and the sleeve chuck 15b inside the through-hole 11 while holding the sleeve chuck 15b from the rear (right side in the figure).

  As shown in FIG. 6, the optical fiber core 5 includes, for example, an optical fiber 3 for transmitting laser light, and a coating layer 4 provided so as to cover the optical fiber 3. A mode stripper 6 is formed on the side surface of the removed optical fiber 3. Here, the mode stripper 6 is formed in an arbitrary range of a region from the tip of the optical fiber 3 (left side in FIG. 6) to the tip of the sleeve chuck 15b (left side in FIG. 6), and propagates through the cladding 2 of the optical fiber 3. The clad mode light is emitted outside the optical fiber 3. The mode stripper 6 is formed, for example, by roughening the outer peripheral surface of the optical fiber 3 by etching or sandblasting, or by grooving the outer peripheral surface of the optical fiber 3 by laser processing or the like.

  The sleeve chuck 15b is formed in a substantially cylindrical shape by a metal having high thermal conductivity such as oxygen-free copper. Here, the surface of the sleeve chuck 15b is gold-plated. In addition, four slits 19 are formed at intervals of 90 degrees in the circumferential direction so as to extend in the longitudinal direction from the distal end of the sleeve chuck 15b (see FIGS. 2 to 4). The sleeve chuck 15b holds the optical fiber core wire 5 with the coating layer 4 by crimping the sleeve chuck 15b with the tip portion abutting against the surface of the taper hole portion 11c with the optical fiber core wire 5 inserted. The connector 10 is configured to be fixed inside the through hole 11 of the connector 10.

  Further, as shown in FIG. 6, the sleeve chuck 15b includes a rear end straight portion 16b provided to engage with the large diameter hole portion 11a and a tip straight provided to engage with the small diameter hole portion 11b. A portion 17b and a tapered portion 18b provided to engage with the tapered hole portion 11c are provided. Here, the tip straight portion 17b and the tapered portion 18b are separated into four by four slits 19, respectively. Moreover, the surface which contacts the coating layer 4 of the front straight part 17b and the taper part 18b is threaded.

  In the optical fiber fixing structure 30b, as shown in FIG. 6, on the distal end side of the small diameter hole portion 11b of the connector 10 and the straight end portion 17b of the sleeve chuck 15b engaged with the small diameter hole portion 11b, 5 is removed, and the side surfaces of the optical fiber 3 are exposed. In the optical fiber fixing structure 30b, as shown in FIG. 6, the end face 4e of the coating layer 4 is retreated from the tip face of the tip straight portion 17b. In the optical fiber fixing structure 30a of the first embodiment, FIG. As shown, the end surface 4e of the coating layer 4 substantially coincides with the tip surface of the tip straight portion 17a.

  In the optical fiber fixing structure 30b configured as described above, first, the sleeve chuck 15b and the chuck screw 20 are sequentially inserted into the through hole 11 of the connector 10 from the rear end side, and then the end portion of the optical fiber core wire 5 is covered. After the layer 4 is removed and the mode stripper 6 is formed, the optical fiber core wire 5 is inserted into the sleeve chuck 15b and the chuck screw 20 from the side from which the coating layer 4 is removed. Can be manufactured by tightening the chuck screw 20 with a torque driver (torque wrench) and crimping the tip of the sleeve chuck 15b.

  As described above, according to the optical fiber fixing structure 30b of the present embodiment, the optical fiber core wire 5 is held by the coating layer 4 and fixed inside the through hole 11 of the connector 10 as in the first embodiment. Since the sleeve chuck 15b is provided with the tip straight portion 17b that engages with the small-diameter hole portion 11b of the through hole 11 of the connector 10, the end portion of the optical fiber 3 is positioned at a predetermined end face inside the connector 10. It can be fixed securely.

  Further, according to the optical fiber fixing structure 30b of the present embodiment, the coating layer 4 of the optical fiber core wire 5 is formed on the distal end side of the distal straight portion 17b engaged with the small diameter hole portion 11b of the through hole 11 of the connector 10. It is removed and the side surface of the optical fiber 3 is exposed. Therefore, for example, of the laser light incident from the end face of the optical fiber 3 due to misalignment of the laser light or the thermal lens effect, the cladding mode light propagating through the cladding 2 of the optical fiber 3 is transmitted from the mode stripper 6. After being radiated to the outside, the clad mode light propagates in the small diameter hole portion 11b of the connector 10 and is incident on the distal end side of the distal straight portion 17b of the sleeve chuck 15b. 4 is difficult to reach. Thereby, the burning of the coating layer 4 by clad mode light can be suppressed.

  Further, according to the optical fiber fixing structure 30b of the present embodiment, the sleeve chuck 15b is made of a metal such as oxygen-free copper, and the surface of the sleeve chuck 15b is gold-plated. The heat generated in 15b can be effectively absorbed, and the heat can be discharged out of the connector 10. Thereby, the burning of the coating layer 4 by clad mode light can be further suppressed.

  Further, according to the optical fiber fixing structure 30b of this embodiment, even if the coating layer 4 of the optical fiber core wire 5 is removed on the distal end side of the distal straight portion 17b of the sleeve chuck 15b, the distal straight portion 17b Since the coating layer 4 of the optical fiber core wire 5 remains on the rear end side, the optical fiber core wire 5 is sufficiently held by the coating layer 4 by the rear end side portion of the tip straight portion 17b of the sleeve chuck 15b. can do.

<< Embodiment 3 of the Invention >>
FIG. 7 is a longitudinal sectional view of the optical fiber fixing structure 30c of the present embodiment.

  In the second embodiment, the optical fiber fixing structure 30b in which the mode stripper 6 is formed on the side surface of the optical fiber 3 is exemplified. However, in this embodiment, the optical fiber in which the mode stripper 6 is not formed on the side surface of the optical fiber 3. The fixing structure 30c is illustrated.

  As shown in FIG. 7, the optical fiber fixing structure 30c has the other configuration as described above except that the mode stripper 6 is not formed on the side surface of the optical fiber 3 from which the coating layer 4 of the optical fiber core wire 5 is removed. This is substantially the same as the configuration of the optical fiber fixing structure 30b of the second embodiment.

  According to the optical fiber fixing structure 30c of this embodiment, as in the first and second embodiments, the sleeve chuck that holds the optical fiber core wire 5 with the coating layer 4 and is fixed inside the through hole 11 of the connector 10. Since 15b is provided with the front straight part 17b engaged with the small diameter hole part 11b of the through hole 11 of the connector 10, the end part of the optical fiber 3 is securely fixed at the position of a predetermined end surface inside the connector 10. be able to.

  In each of the above embodiments, the optical fiber fixing structures 30a to 30c using the sleeve chuck 15a or 15b in which the four slits 19 are formed are illustrated, but the number of the slits formed in the sleeve chuck is It is not limited to this, and any other configuration may be used as long as it facilitates caulking of the tip portion of the sleeve chuck.

  Moreover, in this embodiment, although the optical fiber fixing structure which fixes the edge part of an optical fiber was illustrated, this invention is applicable also to the wire rod fixing structure which fixes the edge part of wires, such as an electric wire, for example. .

  As described above, according to the present invention, the end of the optical fiber can be securely fixed at the position of the predetermined end surface inside the connector, so that not only the optical fiber for transmitting laser light but also the optical fiber is used. Useful in general.

3 Optical fiber 4 Coating layer 5 Optical fiber core wire 6 Mode stripper 10 Connector 11 Through hole 11a Large diameter hole portion 11b Small diameter hole portion 11c Tapered hole portions 15a, 15b Sleeve chucks 16a, 16b Rear end straight portions 17a, 17b Front end straight portion 18a, 18b Tapered portion 19 Slot 30a-30c Optical fiber fixing structure

Claims (6)

An optical fiber fixing structure for fixing, through a sleeve chuck, an end portion of an optical fiber core wire provided with a coating layer inside the through hole of the connector in which the through hole is formed,
A through hole of the connector is formed with a relatively large diameter and has a large diameter hole portion that accommodates a rear end portion of the end portion of the optical fiber core wire, and is formed with a relatively small diameter and the optical fiber core. A small-diameter hole portion that accommodates the distal end portion of the end of the wire, and is formed between the large-diameter hole portion and the small-diameter hole portion, and is formed so as to reduce the diameter from the large-diameter hole portion toward the small-diameter hole portion. Taper holes,
The sleeve chuck has a slit formed so as to extend in the length direction from the tip, and is crimped in contact with the surface of the tapered hole portion in a state where the optical fiber core wire is inserted. A rear end straight portion configured to hold the optical fiber core wire with the coating layer and be fixed inside the through hole of the connector, and to be engaged with the large diameter hole portion And an optical fiber fixing structure comprising: a tip straight portion provided to engage with the small-diameter hole portion; and a tapered portion provided to engage with the tapered hole portion. In the optical fiber fixing structure according to claim 1,
An optical fiber fixing structure in which the surfaces of the straight tip portion and the tapered portion that contact the coating layer are threaded. In the optical fiber fixing structure according to claim 1 or 2,
The sleeve chuck is an optical fiber fixing structure formed of an elastic metal. In the optical fiber fixing structure according to any one of claims 1 to 3,
An optical fiber fixing structure in which, in the small-diameter hole, the optical fiber core protruding from the sleeve chuck has the coating layer removed and the side surface of the optical fiber exposed. In the optical fiber fixing structure according to claim 4,
An optical fiber fixing structure in which, on the distal end side of the distal straight portion of the sleeve chuck engaged with the small-diameter hole portion, the optical fiber core wire has the coating layer removed and the side surface of the optical fiber is exposed. In the optical fiber fixing structure according to claim 4 or 5,
An optical fiber fixing structure in which a mode stripper is formed on a side surface of the optical fiber from which the coating layer has been removed.

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