JP6230553B2 - Terminal structure of loose tube type optical fiber cable and method of manufacturing the terminal structure - Google Patents

Description

  The present invention relates to a terminal structure of a loose tube type optical fiber cable and a manufacturing method of the terminal structure. More specifically, the present invention relates to a loose tube type optical fiber cable terminal structure that can be used in the sea and a method of manufacturing the terminal structure.

  Optical fiber cables are widely used as a medium that plays a central role in the digitization of telecommunications. Further, optical fiber cables are often used in the sea, and as a structure of an optical fiber cable used as a marine cable in the sea, for example, a loose tube type optical fiber cable is known.

  With a loose tube type optical fiber cable, an optical fiber core wire is inserted into a tube (loose tube) formed of plastic such as polybutylene terephthalate (PBT) or polypropylene (PP) through a filler called jelly. If necessary, the optical fiber cable has a structure covered with a sheath together with a tensile member (tension member) (see, for example, Patent Document 1).

JP 2003-322780 A

  For example, since marine cables laid in the sea are long, they may be composed of multiple connected cables. Loose tubes or optical fibers built into cables are also used by being connected in a prescribed manner. It had been. Cables used in the sea are required to have a structure that can withstand the stresses arising from various effects of the sea, such as water pressure and temperature. On the other hand, when water pressure is applied to a loose tube type optical fiber cable in the sea, There is a problem that the jelly filled in the loose tube escapes in a direction where atmospheric pressure is applied, and the jelly leaks from the terminal of the connected loose tube. In addition, if the jelly leaks from the loose tube, the optical fiber jumps out together with the jelly, and eventually the optical fiber core wire may be disconnected or attenuated (loss). There was a need for improvement.

  The present invention has been made in view of the above problems, and when used in the sea, a jelly filled in a loose tube leaks from a terminal to which the loose tube is connected due to the influence of water pressure and the like. An object of the present invention is to provide a loose tube type optical fiber cable terminal structure capable of preventing disconnection of the optical fiber and a method of manufacturing the terminal structure.

To achieve the above object, a terminal structure of a loose tube type optical fiber cable according to the present invention is a terminal structure of a loose tube type optical fiber cable having a loose tube containing an optical fiber, the optical fiber being In the inserted state, a resin tube partially inserted into the inside of the loose tube from the end of the loose tube, the loose tube and the resin tube are inserted, and around the loose tube and the resin tube A sleeve to be fixed, a self-fusing tape wound around the sleeve so as to cover the entire sleeve including both ends of the sleeve, and heat shrink disposed around the self-fusing tape. A terminal portion provided with a tube, and a portion where at least the heat shrinkable tube appears in the terminal portion Characterized by comprising a resin sealing portion for sealing, the.

  The terminal structure of the loose tube type optical fiber cable according to the present invention is characterized in that, in the above-described present invention, the sleeve is fixed to the loose tube and the resin tube via an adhesive.

A method of manufacturing a terminal structure of a loose tube type optical fiber cable according to the present invention is a method of manufacturing a terminal structure of a loose tube type optical fiber cable having a loose tube containing an optical fiber, the resin tube being the optical fiber. A part of the loose tube is inserted into the inside of the loose tube from the end of the loose tube, the sleeve is inserted into the loose tube and the resin tube, and the loose tube and the resin tube are inserted. Fix the periphery, wrap the self-adhesive tape around the sleeve so as to cover the entire sleeve including both ends of the sleeve, and cover the periphery of the self-adhesive tape with a heat-shrinkable tube. Attaching and contracting the heat-shrinkable tube to form a terminal part, at least the heat in the terminal part To cover the portion where condensation tube appears to place the resin, and forming a resin sealing portion by curing the resin.

  The manufacturing method of the terminal structure of the loose tube type optical fiber cable according to the present invention is characterized in that, in the above-described present invention, the sleeve is fixed to the loose tube and the resin tube via an adhesive. .

  In the manufacturing method of the end structure of the loose tube type optical fiber cable according to the present invention, in the above-described present invention, the terminal portion is covered with a cylindrical mold, and the resin is injected into the mold and cured. It is characterized by that.

  According to the terminal structure of the loose tube type optical fiber cable according to the present invention, the terminal portion of the loose tube is securely sealed, and the jelly filled in the loose tube due to the influence of water pressure or the like is connected to the loose tube. A terminal structure of a loose tube type optical fiber cable excellent in water pressure resistance, which can prevent leakage from the optical fiber and disconnection of the optical fiber due to the leakage.

  Also, the manufacturing method of the end structure of the loose tube type optical fiber cable according to the present invention is such that the end portion of the loose tube is securely sealed, and the jelly filled in the loose tube due to the influence of water pressure is connected to the loose tube. Provided is a means for manufacturing a structure excellent in water pressure resistance capable of preventing leakage from a terminal and disconnection of an optical fiber and the like by a simple operation.

It is sectional drawing which showed the one aspect | mode of the loose tube type optical fiber cable. It is sectional drawing which showed the one aspect | mode of the loose tube which accommodated the optical fiber. It is explanatory drawing (state which attached the resin tube) which showed the terminal structure of the cable. It is explanatory drawing (the state which attached the sleeve) which showed the terminal structure of the cable. It is explanatory drawing which showed the terminal structure of the cable (The state which attached the self-fusing tape further). It is explanatory drawing which showed the terminal structure of the cable (The state which attached the self-fusing tape further). It is explanatory drawing (the state which attached the heat contraction tube) which showed the terminal structure of the cable. It is explanatory drawing which showed the state in which the resin sealing part was formed.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
(I) Structure of loose tube type optical fiber cable 1:
FIG. 1 is a cross-sectional view showing an aspect of a loose tube type optical fiber cable 1. The loose tube type optical fiber cable 1 shown in FIG. 1 (hereinafter may be simply referred to as “cable 1”) can be used as a marine cable or the like laid in the sea. Loose tubes 3 (refer to FIG. 2 for the cross-sectional structure) containing the optical fiber 2 together with the jelly 31 and three communication wires 12 are arranged, and the core portion 11 is covered with the sheath 13. The coated core portion 11 is surrounded by two types of strength members 15 and 16, and the strength members 15 and 16 are again covered with the sheath 14. In FIG. 1, the strength member 15 is shown with one of a plurality of 15 attached with a reference numeral 15, and the strength member 16 is also attached with one of a plurality of 16 reference numerals. Show.

  FIG. 2 is a cross-sectional view showing an aspect of the loose tube 3 that accommodates the optical fiber 2. As shown in FIG. 2, the loose tube 3 is a tube that houses the optical fiber 2 together with the jelly 31, and the optical fiber 2 is a single optical fiber (for example, one optical fiber core wire in FIG. 2). Etc.) The mode in which 2 is accommodated is shown. Examples of the optical fiber 2 include an optical fiber, an optical fiber, an optical fiber tape, and the like. The optical fiber is a silica glass fiber coated with an ultraviolet curable resin, Optical fiber cores are known in which a quartz glass fiber is coated with an ultraviolet curable resin or the like so that its diameter is larger than that of the above-described optical fiber. The optical fiber ribbon is formed by arranging several optical fiber strands in parallel and covering them with an ultraviolet curable resin or the like.

  The loose tube 3 is made of, for example, cylindrical polybutylene terephthalate (PBT), polypropylene (PP), or the like, and accommodates the optical fiber 2 together with the jelly 31 therein. The jelly 31 serves to protect the optical fiber 2 from external impacts and prevent moisture from entering the inside of the loose tube 3, and is made of, for example, a jelly compound.

  In the present embodiment, in addition to the loose tube 3, the core portion 11 accommodates a communication line (power supply line) 12 made of an insulated wire. The communication line 12 is built in the cable 1 for communication with the outside, and is configured by coating a metal conductor with a coating material, for example. As the metal conductor, a single wire such as annealed copper, a copper alloy, or aluminum, a stranded wire, or the like can be used. In addition to bare wires, those plated by tin plating or the like may be used. As the coating material, polyolefin resins such as polyethylene and polypropylene, polyvinyl chloride, and the like can be used.

  The sheaths 13 and 14 are extrusion-molded so as to cover the periphery of the loose tube 3 and the communication line 12 and are extruded so as to cover the periphery of the strength members 15 and 16 described later. As a constituent material of the sheaths 13 and 14, for example, a thermoplastic resin composition mainly composed of a polyolefin resin such as polyethylene or polypropylene is used.

  The strength members (tension members) 15 and 16 are made of a wire material such as glass fiber reinforced plastic (GFRP), glass fiber, aramid fiber, aramid FRP, or steel wire, and have, for example, a circular cross-sectional shape. In particular, if a fiber reinforced plastic is used, the weight of the cable 1 is reduced. The strength members 15 and 16 may be used without being twisted in the longitudinal direction, or may be used by being twisted in the circumferential direction as necessary.

(II) Terminal structure X:
Next, the terminal structure X of the loose tube type optical fiber cable according to the present invention that can be applied to the above-described loose tube type optical fiber cable 1 (hereinafter, sometimes simply referred to as “terminal structure X”). This will be described with reference to FIGS. 3 to 8, the side where the optical fiber 2 appears outside is the side (ferrule side) where the optical fiber 2 is connected to the optical fiber of another terminal by a ferrule (not shown), and the ferrule side The opposite side is the cable body side.

  3 to 8 are explanatory views showing a terminal structure X of the loose tube type optical fiber cable 1 (cable 1). FIG. 3 is a view showing a state in which the resin tube 4 is attached. FIG. Furthermore, the figure which showed the state which attached the sleeve 5, FIG.5 and FIG.6 was the figure which showed the state which further attached the self-fusing tape 6, FIG.7 showed the state which attached the heat contraction tube 7 further Each figure is shown. Moreover, FIG. 8 has each shown explanatory drawing which showed the state in which the resin sealing part 8 was formed.

  In the following description (FIGS. 3 to 8), in describing the terminal structure X, one terminal structure X formed with respect to one loose tube terminal 32 will be described as an example. However, the present invention is of course a terminal structure X applicable to all loose tube terminals 32.

(1) Attaching the resin tube 4 to the end 32 of the loose tube:
The resin tube 4 which is a cylindrical member is a terminal of the loose tube in a state where the optical fiber 2 is inserted for the purpose of reinforcing the optical fiber 2 and for the convenience of attaching a ferrule (not shown) as a post process. From 32, a part thereof is inserted into the inside of the loose tube 3, and the other part is attached so as to appear from the outside of the loose tube 3. The resin tube 4 is inserted into the loose tube 3 with a length of 10 to 100 mm from the end 32 of the loose tube, for example, so that the remaining portion of the resin tube 4 appears from the end 32 of the loose tube. It is preferable.

  There is no restriction | limiting in particular as the resin tube 4, For example, a nylon tube, a fluororesin tube, etc. can be used. The length of the resin tube 4 is not particularly limited, but is preferably 50 to 200 mm, for example.

  Moreover, it is preferable to use the resin tube 4 which annealed. By applying the annealing treatment, the strain is removed.

(2) Fixing of the sleeve 5:
FIG. 4 is a view showing a state where the sleeve 5 is further attached. When the resin tube 4 is attached, the sleeve 5 that is a cylindrical member is fixed around the loose tube 3 and the resin tube 4 in a state where the resin tube 4 that appears from the loose tube 3 and the terminal 32 of the loose tube is inserted. . In the present embodiment, as shown in FIG. 4, a mode is shown in which a sleeve 5, which is a cylindrical member, is fixed around an adhesive tube 51 around the loose tube 3 and the resin tube 4. . By fixing using an adhesive, the sleeve 5 is securely and firmly fixed to the loose tube 3 and the resin tube 4, and the workability is also excellent.

  The sleeve 5 is attached for the purpose of fixing the loose tube 3 and the resin tube 4. The sleeve 5 is preferably a so-called split sleeve when an adhesive is used as the fixing means. By using the split sleeve, the injection of the adhesive 51 is facilitated, and the adhesive fixing can be performed simply and firmly, and the workability is improved.

  There is no restriction | limiting in particular as the sleeve 5, For example, metal sleeves, such as a copper sleeve, a stainless steel sleeve, and a lead sleeve, inorganic sleeves, such as a ceramic sleeve, etc. can be used. The length of the sleeve 5 is not particularly limited, but is preferably 5 to 50 mm, for example.

  In the case where an adhesive is used as the fixing means, the adhesive 51 is not particularly limited, and depends on the constituent material of the sleeve 5, the loose tube 3 and the resin tube 4, the required adhesive strength, and the like. Conventionally known adhesives can be used. For example, acrylic adhesives such as cyanoacrylate (cyanoacrylic) adhesives, silicone rubber adhesives, epoxy adhesives, urethane adhesives, polyester adhesives A synthetic adhesive such as a vinyl ester adhesive can be used, but is not limited thereto. In addition, after using the primer apply | coated to each member previously, you may make it adhere each member with the adhesive agent 51. FIG.

(3) Winding of the self-bonding tape 6:
When the sleeve 5 is fixed to the loose tube 3 and the resin tube 4, the self-bonding tape 6 is wound around the sleeve 5 so as to cover the portion including both ends of the sleeve 5. The self-bonding tape 6 serves to securely seal the attached sleeve 5 and the end 32 of the loose tube existing therein, and to prevent the jelly 31 from leaking out.

  5 and 6 are views showing a state where the self-bonding tape 6 is further attached. The self-bonding tape 6 preferably covers the end of the sleeve 5 securely and is sealed. First, as shown in FIG. 5, the self-bonding tape 6 is wound around both ends of the sleeve 5 and the sleeve 5 and the loose tape 6 are loosened. After shaping so that there is no level difference with the tube 3, it is preferable to wind and fix the sleeve 5 so as to cover the periphery as shown in FIG. 6.

  As the self-bonding tape 6, a conventionally known tape can be used. For example, a butyl resin such as butyl rubber, a silicone resin such as silicone rubber, a polyvinyl chloride resin, or a vinyl acetate resin is used as a constituent material. Things can be used. Examples of the self-bonding tape 6 made of butyl resin include “FCO Tape” (trade name, manufactured by Furukawa Electric Power Systems Co., Ltd.). The length of the self-bonding tape 6 (referring to the width that appears outside when wound) is not particularly limited, but is preferably, for example, the length of the sleeve 5 plus 1 to 50 mm.

(4) Attaching the heat shrinkable tube 7:
When the self-bonding tape 6 is wound, a heat shrinkable tube 7 is disposed around the self-bonding tape 6. FIG. 7 shows a state where the heat shrinkable tube 7 is further attached. By attaching the heat shrinkable tube 7, the terminal portion Y is completed. The heat-shrinkable tube 7 is disposed so as to cover the periphery of the self-bonding tape 6, and securely covers and fixes the self-bonding tape 6, and the sleeve 5 and the looseness that exist inside the self-bonding tape 6. The tube end 32 and the like are sealed and fixed, and leakage of the jelly 31 from the end 32 of the loose tube is prevented.

  As the heat-shrinkable tube 7, a conventionally known tube can be used. For example, a tube made of polyolefin, elastic neoprene, fluoroplastic, or the like can be used. The length of the heat-shrinkable tube 7 is not particularly limited, but is preferably, for example, the length of the self-bonding tape 6 plus 1 to 50 mm.

(5) Sealing the terminal portion Y with resin:
The terminal portion Y obtained as described above is a resin that covers at least a portion where the heat shrinkable tube 7 appears, including the other end-treated portion of the cable 1 (other terminal portion not shown). The sealing part 8 is formed and sealed.

  FIG. 8 is an explanatory view showing a state where the resin sealing portion 8 is formed. By sealing at least a portion where the heat shrinkable tube 7 appears in the terminal portion Y by the resin sealing portion 8 formed of the cured resin, it is possible to reliably prevent the jelly 31 from leaking out. As the resin for sealing, it is preferable to use a material capable of maintaining a certain degree of hardness when the resin sealing portion 8 is formed, and examples thereof include curable resins such as thermosetting resins and photo-curable resins. be able to. Specific examples include, but are not limited to, resins such as epoxy resins, acrylic resins, phenol resins, polyimide resins, silicone resins, urethane resins, and unsaturated polyester resins. Further, these resins may be used in the presence of a curing agent. In addition, when using an epoxy resin, there is no limitation on the type, such as one-component, two-component, but it is preferable to use a two-component one in terms of workability and curability. .

  The terminal portion Y is inserted into a cylindrical formwork together with other terminal parts (not shown) for connection with other cables, and is disposed in the front form (not shown). It is also possible to seal with a resin sealing portion 8 formed inside a cylindrical mold in a state where the positioning member is called a positioning member of the terminal portion. If it does in this way, fixation etc. which integrate with other terminal parts which are not shown in figure will be attained.

  In order to ensure sealing of the resin sealing portion 8 and the terminal portion Y, for example, the length L (see FIG. 8) of the end portion on the ferrule side is 5 mm when viewed from the end portion of the heat shrinkable tube 7. It is preferable that the resin sealing portion 8 is formed in the above range.

(III) Manufacturing method of terminal structure X:
Hereinafter, a manufacturing method (forming method) of the terminal structure X of the loose tube type optical fiber cable will be described with reference to FIGS.

  First, the loose tube 3 is taken out from the end of the cable 1 in the previous step, and at the end 32 of the loose tube where the end to be connected is formed, the loose tube 3 having a predetermined length is cut out, so that the optical fiber 2 becomes the loose tube. The jelly 31 is removed from the optical fiber 2 or the like as much as possible. Next, as shown in FIG. 3, a part of the resin tube 4 is inserted into the inside of the loose tube 3 from the end 32 of the loose tube while the optical fiber 2 is inserted.

  The resin tube 4 is inserted into the inside of the loose tube end 32, and in the state where a part of the resin tube 4 appears from the end 32 of the loose tube, as shown in FIG. The resin tube 4 appearing from the tube 32 and the end 32 of the loose tube is inserted and fixed around the loose tube 3 and the resin tube 4. FIG. 4 shows a state in which the sleeve 5 which is a cylindrical member is fixed around the loose tube 3 and the resin tube 4 via the adhesive 51. In this case, the adhesive 51 is as described above. First, an adhesive 51 is applied to a gap between the sleeve 5, the loose tube 3, and the resin tube 4 in a state where the primer is applied to a portion to be bonded to the loose tube 3, the resin tube 4, and the sleeve 5 and temporarily fixed. It is preferable to fix each member by injecting. Further, by using a split sleeve as the sleeve 5, the injection of the adhesive 51 can be facilitated, the adhesion and fixing can be performed simply, and workability is improved. In addition, the adhesive fixing of each member is also made strong.

  When the sleeve 5 is fixed, as shown in FIGS. 5 and 6, the self-bonding tape 6 is wound around and attached to the sleeve 5 so as to cover the portion including both ends of the sleeve 5. As shown in FIG. 5, the self-bonding tape 6 is wound (attached) by winding a small self-bonding tape 6 around both ends of the sleeve 5 and shaping the step between the sleeve 5 and the loose tube 3 as much as possible. As shown in FIG. 6, it is preferable to wind the self-bonding tape 6 so as to cover the periphery of the sleeve 5 because the end of the sleeve 5 is surely covered and sealed.

  When the self-bonding tape 6 is wound, as shown in FIG. 7, the heat-shrinkable tube 7 is attached so as to cover the periphery of the self-bonding tape 6, and the heat-shrinkable tube 7 is shrunk by heating with a dryer (not shown) or the like. And fix it. In this case, when using a resin tube 4 that is relatively weak against heat, such as a nylon tube, it is necessary to protect the resin tube 4. The terminal portion Y is completed by attaching and shrinking the heat shrinkable tube 7. It should be noted that the end portion of the heat shrinkable tube 7 may be filled with a resin (such as a curable resin) used in a subsequent process and cured so as to close a gap or the like as much as possible.

  When the terminal portion Y is completed in this way, for example, after attaching a ferrule (not shown) to the terminal of the optical fiber 2, a resin is applied so as to cover at least a portion where the heat shrinkable tube 7 appears in the terminal portion Y. The resin sealing portion 8 is formed by curing the resin. The resin sealing portion 8 is formed, for example, by covering a cylindrical mold (not shown), injecting a resin such as a curable resin into the mold, and curing the resin such as the curable resin. Also good. The terminal portion Y is formed inside a cylindrical formwork in a state of being positioned by a positioning member of a terminal portion called a front insert (not shown) together with another terminal portion (not shown) for connection with another cable. You may make it seal with the resin sealing part 8 made.

  When the resin sealing portion 8 is formed in this way, a power line contact and an optical fiber ferrule (not shown) are attached to the front insert, or an optical fiber or the like appearing from the resin sealing portion 8 is attached to the end of another cable. A subsequent process such as connection to an optical fiber or the like is performed, and the cables 1 are connected to each other.

(IV) Effects of the present invention:
The terminal structure of the loose tube type optical fiber cable 1 according to the present embodiment described above is a resin part of which is inserted into the inside of the loose tube 3 from the terminal 32 of the loose tube in a state where the optical fiber 2 is inserted. The tube 5, the loose tube 3 and the resin tube 4 are inserted, the sleeve 5 fixed around the loose tube 3 and the resin tube 4, and the periphery of the sleeve 5 so as to cover the portion including both ends of the sleeve 5. A terminal portion Y having a self-adhesive tape 6 wound around the heat-adhesive tape 6 and a heat-shrinkable tube 7 disposed around the self-adhesive tape 6, and at least a portion where the heat-shrinkable tube 7 appears in the terminal portion Y is sealed. And a resin sealing portion 8 to be stopped. With this terminal structure X, the terminal 32 of the loose tube is securely sealed, and the jelly 31 filled in the loose tube 3 leaks from the terminal 32 to which the loose tube 3 is connected due to the influence of water pressure and the like. The end structure X of the loose tube type optical fiber cable which can prevent the disconnection of the optical fiber 2 and is excellent in water pressure resistance.

  The present invention can be applied to, for example, a loose tube type optical fiber cable 1 used in the sea, and a loose tube to which the loose tube 3 is connected to a jelly 31 filled in the loose tube 3 due to the influence of water pressure or the like. It is possible to reliably prevent leakage from the terminal 32 and disconnection of the optical fiber 2 caused thereby. In addition, it is not limited to use in the sea, and can be widely used as a terminal structure of the loose tube type optical fiber cable 1.

(V) Variation of embodiment:
The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and has the configuration of the present invention and can achieve the objects and effects. It goes without saying that modifications and improvements within the scope are included in the content of the present invention. Further, the specific structure, shape, and the like in carrying out the present invention are not problematic as other structures, shapes, and the like as long as the objects and effects of the present invention can be achieved. The present invention is not limited to the above-described embodiments, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.

  For example, in the above-described embodiment, the loose tube type optical fiber cable 1 has been described by taking the structure shown in FIG. 1 as an example. However, the present invention is a loose tube type having a loose tube 3 containing the optical fiber 2. The terminal structure X of the optical fiber cable 1 can be widely applied, and the structure and the like are not limited to those shown in FIG. Therefore, for example, the structure of the cable 1 can be arbitrarily determined such that a single strength member 15 or 16 is placed at the center and the loose tube 3 is disposed around the strength member. The number, arrangement, etc. of 3, the strength members 15, 16, etc., the type, number, arrangement, etc. of members interposed other than the loose tube 3, and whether to make a multilayer or a single layer, etc., are arbitrarily determined Can do.

In the above-described embodiment, as illustrated in FIG. 4, the sleeve 5 that is a tubular member is fixed around the loose tube 3 and the resin tube 4 using an adhesive 51. The means for fixing the sleeve 5 to the loose tube 3 and the resin tube 4 is not limited to the means using an adhesive as described above. For example, the sleeve 5 is connected to the loose tube 3 and the resin tube via an adhesive tape (not shown). 4 is fixed around the sleeve 4, or the sleeve 5 is crushed with pliers, a dedicated tool or the like, so that the sleeve 5 and the resin tube 4 are caulked (so-called caulking). Or a sleeve 5 formed of a material that can be heat-welded (heat-welded), etc., and fixed to the sleeve 5 by heat-welding. And it may be.
In addition, the specific structure, shape, and the like in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

  INDUSTRIAL APPLICABILITY The present invention can be advantageously used as a means for providing a terminal structure of a loose tube type optical fiber cable that is excellent in water pressure resistance and can prevent leakage of jelly from the terminal of a loose tube. The availability is high.

DESCRIPTION OF SYMBOLS 1 ... Loose tube type optical fiber cable 11 ... Core part 12 ... Communication line 13, 14 ... Sheath 15, 16 ... Strength body 2 ... Optical fiber 3 ... Loose tube 31 ... Jerry 32 ... Loose End of tube 4 ... Resin tube 5 ... Sleeve 51 ... Adhesive 6 ... Self-adhesive tape 7 ... Heat-shrinkable tube 8 ... Resin sealing part X ... Terminal structure Y ... Terminal part

Claims (5)

A terminal structure of a loose tube type optical fiber cable having a loose tube containing an optical fiber,
In a state where the optical fiber is inserted, a resin tube, a part of which is inserted from the end of the loose tube into the loose tube,
A sleeve that is inserted through the loose tube and the resin tube and fixed around the loose tube and the resin tube;
A self-bonding tape wound around the sleeve so as to cover the entire sleeve including both ends of the sleeve;
A heat shrinkable tube disposed around the self-bonding tape;
A terminal structure of a loose tube type optical fiber cable, comprising: a resin sealing portion that seals at least a portion where the heat shrinkable tube appears in the terminal portion.   The end structure of the loose tube type optical fiber cable according to claim 1, wherein the sleeve is fixed to the loose tube and the resin tube via an adhesive. A method of manufacturing a terminal structure of a loose tube type optical fiber cable having a loose tube containing an optical fiber,
With the resin tube inserted through the optical fiber, a part of the resin tube is inserted into the loose tube from the end of the loose tube,
A sleeve is inserted around the loose tube and the resin tube, and is fixed around the loose tube and the resin tube.
A self-fusing tape is wrapped around the sleeve so as to cover the entire sleeve including both ends of the sleeve,
A heat-shrinkable tube is attached so as to cover the periphery of the self-adhesive tape, and the heat-shrinkable tube is contracted to form a terminal portion,
A terminal structure of a loose tube type optical fiber cable, wherein a resin is disposed so as to cover at least a portion where the heat shrinkable tube appears in the terminal portion, and the resin is cured to form a resin sealing portion. Method.   The method for manufacturing a terminal structure of a loose tube type optical fiber cable according to claim 3, wherein the sleeve is fixed to the loose tube and the resin tube via an adhesive.   The end structure of the loose tube type optical fiber cable according to claim 3 or 4, wherein the end portion is covered with a cylindrical mold, and the resin is injected into the mold and cured. Manufacturing method.

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