JP2013137358A - Terminal processing method for optical fiber cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal processing method for an optical cable, which is capable of improving workability in connection to an optical module.SOLUTION: In a folding step after a sheath removal step, cuts 26a and 26b are formed on a removal part 17a of a metal tape 17 along an axial line of a coated optical fiber 14 and in opposite positions on an outer periphery of the metal tape 17 (in the vicinity of an overlap part 25), so that the removal part 17a of the metal tape 17 can be easily peeled from on an inner tube 15. Then, the removal part 17a of the metal tape 17 is folded to the outside of an end part of a sheath 18. Thus, a folded part 17b of the metal tape 17 is formed on the outside of the end part of the sheath 18.

Description

  The present invention relates to an optical fiber cable terminal processing method.

  A conventional optical module includes a circuit board on which a photoelectric conversion unit connected to an optical fiber of an optical fiber cable (hereinafter simply referred to as an optical cable) is mounted, and a metal housing that houses the circuit board. . In this optical module, an input / output electric signal is converted into an optical signal by a photoelectric conversion unit, and signal transmission using the optical signal is performed.

  In the optical cable used in this optical module, the outer periphery of a single-core or multi-core optical fiber is covered with a metal tube, and the outer periphery is provided with tensile strength fibers that increase the tensile strength of the optical cable. A metal tube type optical cable covered with a cover is known (for example, see Patent Document 1).

  By the way, an optical cable used for connecting an electronic device such as a personal computer has an inner tube made of an insulating resin on the outer periphery of the optical fiber, has a tensile fiber on the outer periphery, and heat transfer on the outer periphery of the tensile fiber. It has a metal braid as a member and has a jacket on its outer periphery. In the case of a metal braid, a step of braiding a tin-plated conductive wire is required, and a copper metal tape is used to improve productivity (production line speed). There are two types of winding of the metal tape: a type that is vertically attached along the axis of the optical fiber, and a type that is spirally wound around the outer periphery of the optical fiber.

Japanese Patent No. 3898655

  However, in the connection work with the optical module, the outer cover removing process of unwrapping or removing the wound metal tape to expose the optical fiber and the folding process of turning back the removed end of the metal tape become complicated, and work efficiency is improved. It is causing a decline.

  The objective of this invention is providing the terminal processing method of the optical cable which can aim at the improvement of workability | operativity in the connection operation | work with an optical module.

An optical cable terminal processing method according to the present invention capable of solving the above-described problems is provided with an end of the outer sheath of an optical cable having a tape-shaped metal layer on the outer side of an optical fiber, and an outer sheath on the outer side of the metal layer An optical cable terminal processing method comprising: a jacket removing step of removing a predetermined length from a portion; and a folding step of folding the metal layer by a predetermined length and covering the periphery of an end of the jacket;
In the folding step, a cut portion having a predetermined length is formed along the folding direction from the exposed end portion of the metal layer after the outer cover removing step, and the metal layer is peeled off from the cut portion to form the outer cover. It is characterized by being folded around the edge.

  In the optical cable terminal processing method according to the present invention, it is preferable that the metal layer is spirally wound around the outside of the optical fiber.

  In the optical cable terminal processing method according to the present invention, it is preferable that the cut portion is formed in a spiral shape along the winding direction.

  In the optical cable terminal processing method according to the present invention, it is preferable that the cut portion is formed at an end portion of the metal layer at the beginning of winding.

  Further, in the optical cable terminal processing method according to the present invention, after the folding step, the outer cover and the metal layer interposed inside the outer cover and the crimped metal layer are crimped to the terminal fixture. It is preferable to have.

  According to the optical fiber terminal processing method according to the present invention, the folding process includes forming a cut portion having a predetermined length from the end of the exposed metal layer along the folding direction after the outer cover removing process, and cutting the metal layer. It peels from the part and is folded back. Thereby, the workability | operativity in the connection operation | work with an optical module can be aimed at.

It is a perspective view which shows an example of the optical module which concerns on this invention. It is sectional drawing of the optical cable of FIG. It is a perspective view which shows the housing | casing inside the optical module of FIG. It is the schematic which shows one Embodiment of the terminal processing method of the optical cable of this invention, (a) shows the state from which the jacket of the optical cable was removed, (b) shows the state by which the cut part was formed in the metal tape. (C) shows a state where the metal tape is folded. It is a perspective view which shows an example of the optical cable terminal fixture of FIG. It is a perspective view which shows the attachment state of FIG. It is a perspective view which shows the crimping state of FIG. It is sectional drawing in the AA of FIG. It is the schematic which shows another embodiment of the terminal processing method of the optical cable of this invention, (a) shows the state by which the jacket of the optical cable was removed, and (b) the state by which the cut | notch part was formed in the metal tape (C) shows a state in which the metal tape is folded. It is the schematic which shows another embodiment of the terminal processing method of the optical cable of this invention, (a) shows the state from which the jacket of the optical cable was removed, (b), the notch | incision part was formed in the metal tape The state is shown, and (c) shows a state where the metal tape is folded.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an optical cable terminal processing method according to the invention will be described with reference to the drawings.

(Embodiment 1)
An optical module is used for transmission of signals (data) in optical communication technology, etc., and is electrically connected to an electronic device such as a connected personal computer, and converts an input / output electric signal into an optical signal. An optical signal is transmitted.

  As shown in FIG. 1, in the optical module 10 of this embodiment, a connector module is connected to an end portion of an optical cable 11. This connector module includes an electrical connector 12 provided on the distal end side, and an exterior housing 13 that covers a metal housing 20 (see FIG. 3) that houses a circuit board 24. A connection portion between the optical cable 11 and the housing 20 is covered with a boot 19.

  As shown in FIG. 2, the optical cable 11 has an optical fiber ribbon 14a in the center as seen in its cross section. The optical fiber ribbon 14a is obtained by integrating a plurality (four in this example) of optical fibers 14 in parallel on a plane and integrating them in a tape shape with a coating resin. The optical fiber ribbon 14 a is accommodated inside the inner tube 15. An intervening layer 16 is provided around the inner tube 15 along a bundle of tensile strength fibers. A metal tape 17 that is a metal layer is provided on the outer periphery of the intervening layer 16. An outer cover 18 made of an insulating resin is provided on the outer periphery of the metal tape 17.

  As the optical fiber core 14, an optical fiber (AGF: All Glass Fiber) whose core and clad are quartz glass, an optical fiber (HPCF: Hard Plastic Clad Fiber) whose clad is made of hard plastic, and the like can be used. When a thin HPCF having a glass core diameter of 80 μm is used, it is difficult to break even if the optical fiber 14 is bent to a small diameter. The plurality of optical fiber core wires 14 can be accommodated in the inner tube 15 as a single core without being taped. However, when the optical fiber core wires 14 are taped, the single optical fiber core wires 14 cross each other and the lateral pressure is increased. The occurrence of microbend loss due to this can be prevented. A plurality of optical fiber ribbons 14a may be provided.

  The inner tube 15 is made of an insulating resin such as PVC (Polyvinylchloride) which is a non-halogen flame retardant resin. For example, the inner tube 15 has an outer diameter of 2.0 mm and a thickness of 0.55 mm. The intervening layer 16 is, for example, an ultrafine-diameter aramid fiber, and is built in the optical cable 11 in a bundled state. The intervening layer 16 has a tensile strength function in the optical cable 11. Hereinafter, the intervening layer 16 is referred to as a tensile strength fiber.

  The metal tape 17 according to the present embodiment has, for example, two tin-plated copper tapes vertically attached to the outer periphery of the intervening layer 16 and has a function as a heat dissipation layer. The thermal conductivity of the metal tape 17 is 400 W / m · K, for example. The jacket 18 is made of an insulating resin such as polyolefin. The jacket 18 has, for example, an outer diameter of 4.2 mm and a thickness of 0.5 mm. The optical cable 11 having such a configuration is excellent in the lateral pressure characteristics of the optical fiber core wire 14, the flexibility as the cable, and is excellent in heat dissipation.

  As shown in FIG. 3, the housing 20 is a cylindrical housing member having a substantially rectangular cross section, and houses a circuit board 22 on which a photoelectric conversion unit 21 to which the optical fiber core wire 14 is connected is mounted. The storage space is defined. In addition, the housing 20 is provided with an electrical connector 12 at the front end, and an optical cable terminal fixture 30 that fixes the optical cable 11 is connected to the rear end. The housing 20 is made of a metal material having high thermal conductivity (preferably 100 W / m · K or more) such as steel (Fe-based), tin (tin-plated copper), stainless steel, copper, brass, and aluminum. Yes.

  An embodiment of an optical cable terminal processing method according to the present invention will be described with reference to FIG. The optical cable 11 of the present embodiment has an inner tube 15 on the outside of the optical fiber core wire 14, a tensile strength fiber 16 on the outside, a metal tape 17 on the outside, and an outer side on the metal tape 17. A cover 18 is provided.

(Coating removal process)
As shown in FIG. 4A, in the jacket removal process of the optical cable 11, the metal tape 17 is exposed by removing the jacket 18 of the optical cable 11 from the end by a predetermined length. The metal tape 17 is vertically attached so as to form an overlapping portion 25 along the axis of the optical fiber core wire 14. In the overlap portion 25, the metal tapes 17 may be bonded to each other.

(Wrapping process)
The folding process is a process in which the metal tape 17 is folded over a predetermined length and is put around the end of the outer cover 18. First, as shown in FIG. 4 (b), the removal portion 17a of the metal tape 17 is opposed to the opposing position along the axis of the optical fiber core 14 and on the outer periphery of the metal tape 17 (in the present embodiment, in the vicinity of the overlapping portion 25). ), Two notches 26a and 26b are formed by a dedicated jig.

  Thereby, the removal part 17a of the metal tape 17 can be easily peeled up and down from the inner tube 15 even if the overlapping part 25 is bonded. In the drawing, the thick solid line is the cut portion 26a on the front side of the paper, and the thick broken line is the cut portion 26b on the back side of the paper. Further, the cut portions 26a and 26b are not limited to two, and may be formed three or more. Moreover, the formation positions of the notches 26a and 26b can be arbitrarily selected.

  As shown in FIG. 4C, the removal portion 17 a of the metal tape 17 is folded back outside the end portion of the outer cover 18. As a result, the folded portion 17 b of the metal tape 17 is formed outside the end portion of the outer cover 18. And the inner tube 15 is cut | disconnected and removed in the part from which the metal tape 17 was removed by the removal part 17a of the metal tape 17 being folded. Therefore, workability in connection work with the optical module 10 can be improved. Note that unnecessary portions of the folded metal tape 17 may be cut and removed.

(Crimping process)
The crimping step is a step of crimping the outer cover 18, the metal tape 17 interposed inside the outer cover 18, and the folded portion 17 b of the folded metal tape 17 to the terminal fixture after the folding process.
As shown in FIG. 5, the optical cable terminal fixture 30 has a two-part configuration including a main body portion 31 and a crimping portion 32. The main body 31 includes a jacket fixing portion 33 that fixes the jacket 18, a cable insertion passage 35 through which the optical fiber core wire 14 is inserted, and a flat plate-like base portion 34 that is disposed at the front end of the main body 31. , Is composed of. Since the outer peripheral surface of the outer cover fixing portion 33 is smoothed by surface processing, it can be smoothly performed without damaging the metal tape 17 and the outer cover 18 by caulking. On both sides of the cable insertion passage 35 of the base portion 34, there are concave portions 36 for drawing a tensile strength line in which a plurality of tensile strength fibers 16 of the optical cable 11 are bundled to the rear side of the outer jacket fixing portion 33.

  The crimping part 32 is a U-shaped crimping tool that is crimped to the outer peripheral surface of the jacket fixing part 33, and has a crimping piece 38 at both ends and a notch 39 adjacent to the crimping piece 38. . In the crimping portion 32, the crimping piece 38 on the other end side is crimped on the cutout portion 39 on the one end side when crimping to the jacket fixing portion 33. Since the inner peripheral surface 37 of the crimping portion 32 is smoothed by surface processing, the caulking operation can be smoothly performed without damaging the outer jacket 18.

First, an example of a procedure for attaching the optical cable 11 to the optical cable terminal fixture 30 will be described.
As shown in FIG. 6, the optical fiber core wire 14, the inner tube 15, and the tensile fiber 16 of the optical cable 11 are inserted into the cable insertion passage 35 of the main body 31, and the folded portion 17 b and the jacket 18 of the metal tape 17 are connected. It is put on the outer periphery of the jacket fixing part 33.

  Next, the tensile strength fiber 16 inserted through the cable insertion passage 35 is drawn out from the surface side of the base portion 34 to the jacket fixing portion 33 side through the recess 36. Then, the crimping part 32 is moved to the folded part 17b of the metal tape 17 folded to the outer peripheral side of the outer jacket 18, and the pulled tensile strength fiber 16 is pushed into the inner peripheral surface 37 side of the crimping part 32. It is.

  Next, as shown in FIG. 7, the crimping portion 32 is crimped over the entire circumference of the outer peripheral surface of the folded portion 17 b of the metal tape 17 by a dedicated crimping jig. At this time, the crimping piece 38 on the other end side is crimped on the notch 39 on the one end side. As a result, as shown in FIG. 8, the optical cable 11 is held and fixed to the optical cable terminal fixture 30, and the jacket 18, the metal tape 17, and the tensile fiber 16 are interposed between the jacket fixing portion 33 and the crimping portion 32. It is pinched.

  Finally, the optical cable terminal fixture 30 is coupled to the rear end portion of the housing 20 so that the housing 20 and the optical cable terminal fixture 30 are physically and thermally connected. That is, the housing 20 and the metal tape 17 of the optical cable 11 are thermally connected.

  As described above, the optical cable 11 has the metal tape 17 between the tensile strength fiber 16 and the jacket 18, the metal tape 17 is interposed between the jacket fixing portion 33 and the jacket 18, and the metal tape 17 is fixed to the jacket. The outer periphery of the outer cover 18 is crimped from the outer periphery of the outer cover 18 to the outer peripheral surface of the outer cover fixing part 33 by the crimping part 32 crimped to the outer peripheral surface of the part 33. By doing so, the metal tape 17 is firmly and thermally connected to the jacket fixing portion 33, and heat can be released from the housing 20 connected to the jacket fixing portion 33 to the optical cable 11 side. Then, heat can be efficiently released from the metal tape 17 through the jacket 18 to the outside.

  Furthermore, the optical cable terminal fixture 30 that is thermally connected by soldering the metal tape 17 to the housing 20 is more firmly coupled to the housing 20, so that the housing 20 and the optical cable terminal fixture 30 can be connected to each other. Thermally connected. Thereby, the heat generated in the housing 20 can be dissipated more efficiently from the optical cable terminal fixture 30, and the heat-resistant optical module 10 can be obtained.

(Embodiment 2)
Next, another embodiment of the optical cable terminal processing method according to the present invention will be described with reference to FIG. In addition, description of the same structure as the said embodiment is abbreviate | omitted by attaching | subjecting the same code | symbol. Moreover, about a crimping | compression-bonding process, description is abbreviate | omitted by using the optical cable terminal fixture of the same structure.

(Coating removal process)
As shown in FIG. 9A, in the jacket removal process of the optical cable 11, the metal tape 17 is exposed by removing the jacket 18 of the optical cable 11 from the end by a predetermined length. The metal tape 17 is spirally wound from the left side to the right side in the drawing so as to form a spiral overlap portion 25 along the axis of the optical fiber core wire 14. Therefore, the metal tape 17 cannot be unwound from the left end. In the case of spiral winding, the metal tapes 17 may be bonded to each other at the overlapping portion 25.

(Wrapping process)
As shown in FIG. 9B, first, two cut portions 26a and 26b are formed in the removal portion 17a of the metal tape 17 along the axis of the optical fiber core 14 and at opposing positions on the outer periphery of the metal tape 17. It is formed by a dedicated jig. That is, the notches 26 a and 26 b are formed at the end of the metal tape 17 at the beginning of winding. Thereby, even if the removal part 17a of the metal tape 17 is the spiral winding to which the overlap part 25 was adhere | attached, it can be divided | segmented up and down in the figure, and can be easily peeled off on the inner tube 15. FIG.

  As shown in FIG. 9C, the removal portion 17 a of the metal tape 17 is folded back outside the end portion of the outer cover 18. As a result, the folded portion 17 b of the metal tape 17 is formed outside the end portion of the outer cover 18. And the inner tube 15 is cut | disconnected and removed in the part from which the metal tape 17 was removed by the removal part 17a of the metal tape 17 being folded. Therefore, even in the case of the spirally wound metal tape 17, the workability in the connection work with the optical module 10 can be improved as described above. Note that unnecessary portions of the folded metal tape 17 may be cut and removed.

(Embodiment 3)
Next, still another embodiment of the optical cable terminal processing method according to the present invention will be described with reference to FIG. In addition, description of the same structure as the said embodiment is abbreviate | omitted by attaching | subjecting the same code | symbol. Moreover, about a crimping | compression-bonding process, description is abbreviate | omitted by using the optical cable terminal fixture of the same structure.

(Coating removal process)
As shown in FIG. 10A, in the jacket removal process of the optical cable 11, the metal tape 17 is exposed by removing the jacket 18 of the optical cable 11 from the end by a predetermined length. The metal tape 17 is spirally wound from the left side to the right side in the drawing so as to form a spiral overlapping portion 25 along the axis of the optical fiber core wire 14 as described above.

(Wrapping process)
As shown in FIG. 10 (b), first, two cut portions 26a are formed on the removal portion 17a of the metal tape 17 along the spiral overlap portion 25 that is the winding direction and at opposing positions on the outer periphery of the metal tape 17. , 26b are spirally formed by a dedicated jig. That is, the notches 26 a and 26 b are formed at the end of the metal tape 17 at the beginning of winding. The first cut portions 26 a and 26 b are formed along the axis of the optical fiber core wire 14. Thereby, even if the removal part 17a of the metal tape 17 is a spiral winding to which the overlapping part 25 is bonded, it can be divided into upper and lower parts in the drawing and can be easily peeled off from the inner tube 15.

  As shown in FIG. 10 (c), the connecting portion 17c of the metal tape 17 is removed without being removed. Then, the connecting portion 17 c of the metal tape 17 is crimped or soldered to the housing 20. Further, the folded portion 17b of the metal tape 17 is folded to the outside of the end portion of the outer cover 18, and the inner tube 15 is cut and removed at the portion where the metal tape 17 is removed. Therefore, even in the case of the spirally wound metal tape 17, the workability in the connection work with the optical module 10 can be improved as described above. Note that unnecessary portions of the folded metal tape 17 may be cut and removed.

  As described above, the end processing method of the optical cable according to each of the above-described embodiments has the outer sheath 18 of the optical cable 11 having the metal tape 17 outside the optical fiber core wire 14 and the outer sheath 18 outside the metal tape 17. An outer cover removing step for removing a predetermined length from the portion, and a folding step for folding the metal tape 17 around the end of the outer cover 18 by a predetermined length. In the folding process, after the outer cover removing process, cut portions 26a and 26b having a predetermined length are formed along the folded direction from the exposed end portion of the metal tape 17, and the metal tape 17 is peeled off from the cut portions 26a and 26b. Then, it is folded around the end of the outer cover 18.

  According to the optical cable terminal processing method having the above-described configuration, in the folding step, the cut portions 26a and 26b having a predetermined length are formed from the exposed end portion of the metal tape 17 along the folding direction after the outer cover removing step. Since the removal part 17a of the tape 17 is peeled off from the notches 26a and 26b and easily removed, the workability in the connection work with the optical module 10 can be improved.

  Further, if the metal tape 17 is spirally wound around the optical fiber core wire 14, the heat transfer area of the metal tape 17 can be increased, so that the heat dissipation efficiency can be improved.

  Further, if the notches 26a and 26b are formed in a spiral shape along the winding direction, the metal tape 17 can be easily unwound when the metal tape 17 is unwound and its end is crimped or soldered to the housing 20. be able to. Thereby, the workability in the connection work with the optical module 10 can be further improved.

  Usually, in the case of spiral winding by lap winding, it cannot be unwound from the end portion at the beginning of winding, but if the cut portions 26a and 26b are formed at the end portion at the start of winding of the metal tape 17, the cut portion 26a. , 26b, the metal tape 17 can be easily unwound.

  In addition, if the metal tape 17 is crimped to the optical cable terminal fixture 30 after the folding process, the tensile strength fiber 16 is sandwiched by the optical cable terminal fixture 30 together with the jacket 18 of the optical cable 11 and the metal tape 17. Therefore, it is possible to form a terminal structure of an optical cable that is strong against pulling.

  In addition, the terminal processing method of the optical cable of this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

DESCRIPTION OF SYMBOLS 10 ... Optical module, 11 ... Optical cable, 14 ... Optical fiber core wire, 15 ... Inner tube, 16 ... Intervening layer (tensile fiber), 17 ... Metal tape (metal layer), 17a ... Removal part, 17b ... Folding part, 17c DESCRIPTION OF SYMBOLS ... Connection part, 18 ... Jacket | cover, 20 ... Housing | casing, 21 ... Photoelectric conversion part, 22 ... Circuit board, 25 ... Overlapping part, 26a, 26b ... Notch part, 30 ... Optical cable terminal fixture

Claims (5)

A jacket removing step of removing a predetermined length of the jacket of the optical fiber cable having a tape-shaped metal layer outside the optical fiber and having a jacket outside the metal layer; and the metal layer A folding step of folding a predetermined length around the end portion of the jacket, and a terminal processing method for an optical fiber cable,
In the folding step, a cut portion having a predetermined length is formed from the exposed end portion of the metal layer after the outer cover removing step, and the metal layer is peeled off from the cut portion and is formed around the outer cover end portion. An end processing method for an optical fiber cable, wherein the end processing method is performed. In the terminal processing method of the optical fiber cable according to claim 1,
An end processing method for an optical fiber cable, wherein the metal layer is spirally wound around the outer side of the optical fiber. In the terminal processing method of the optical fiber cable according to claim 2,
The method of processing an end of an optical fiber cable, wherein the cut portion is formed in a spiral shape along a winding direction. In the optical fiber cable terminal processing method according to any one of claims 1 to 3,
The method of processing an end of an optical fiber cable, wherein the cut portion is formed at an end portion of the metal layer at the beginning of winding. In the terminal processing method of the optical fiber cable according to claim 1,
After the folding step, there is a crimping step of crimping the outer layer, the metal layer interposed inside the outer jacket, and the folded metal layer to a terminal fixture, and terminating the optical fiber cable. Method.

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