JP2005258371A - Method of manufacturing mechanical splice - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a mechanical splice which has a superior connection hole (hole diameter) for high-precision butt splicing of optical fibers and easily and surely splices and fixes the optical fibers. <P>SOLUTION: A sleeve method mechanical splice 29 comprises splicing parts for butt splicing of optical fibers, fixing parts for splicing and fixing the optical fibers, and auxiliary fixing parts. The cylindrical splicing parts having an optical fiber connection hole (hole diameter) which is perfectly circular and is superior in surface shape and is straight is manufactured by straightly supporting a matrix core wire having an optical fiber shape to electrodeposit a metal thereon while rotating it on its axis by electrocasting in a cathode rotation system and processing external shape dimensions of an obtained electrocast material and removing the core wire. The fixing parts are metallic tubes which have caulking parts for optical fiber coating cords in both ends and are soft to be suitable for caulking, and the auxiliary fixing parts are metallic tubes having such an internal diameter that optical fiber coating parts can be stored therein when splicing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a method for manufacturing a mechanical splice in which two optical fibers are connected to each other with low connection loss, and the optical fiber or the covering cord is fixed without the optical fiber being bent or dropped.

In recent years, with the spread of the Internet, the volume of information distribution has increased, and the demand for optical fiber connection has been increasing. Mechanical splices that butt-connect optical fibers are mainly used in permanent connection locations such as mainline facilities, and are mechanically held and fixed so that the components that butt-connect two optical fibers and the optical fiber butt are not dropped. There is a demand for a mechanical splice that has a low connection loss and has a highly reliable connection portion.

FIG. 1 and FIG. 2 show a mechanical splice by a general sleeve method. FIG. 1A is a cross-sectional view of a connecting part 2 of a cylindrical body having a connection hole (hole diameter) 1 of an optical fiber, and FIG. FIG. 2 is a cross section of a tube-shaped fixed part 4 having an inner diameter 3 of a fiber-coated cord shape, and FIG. 2 is a cross section of an integrated sleeve method mechanical splice (see Non-Patent Document 1). In addition to the sleeve method, the mechanical splice connection method includes a connection method using a V-groove method in which a V-groove is used in the connection portion.
“Optcom 1996 April No. 77 Chapter 5 Optical Fiber Connection, Facility p.70 Figure 5-7 (a)”

In the mechanical splice of the sleeve method, an optical fiber is inserted from both ends of a connection hole (hole diameter) that is slightly larger than the optical fiber, and the axis is aligned by the outer diameter of the optical fiber. Further, the optical fiber or the covering cord is fixed by a holding force by a fixing component or an adhesive.

In the above connection method, in particular, the connection hole (hole diameter) of the connection component that abuts the optical fiber is a perfect circle, has a surface shape of the optical fiber, and is straightened. It is difficult to obtain by molding or drilling, and for fixing the optical fiber or the coated cord part, there is a need for a secure and reliable fixing part that does not break or drop off the optical fiber and has good workability. The

As a method for solving such a problem, both ends of a core wire that is a perfect circle and has a surface shape of an optical fiber are supported straight by a base material by electrocasting using a cathode rotation method, and metal electrodeposition is performed on the surface of the core wire. By removing the core wire of the obtained electroformed body, a connection component having a highly accurate connection hole (hole diameter) can be obtained. Also, the optical fiber can be fixed firmly by crimping the covering cord portion using a soft metal tube as a fixing component. Furthermore, by using an auxiliary fixing part that adjusts the inner diameter of the fixing part in combination, it is possible to perform fixing corresponding to a coating cord having different outer diameters.

The present invention has been made in view of such circumstances, and its purpose is to manufacture a mechanical splice by a sleeve method in which two optical fibers are connected to each other with a low connection loss, and the optical fibers are fixed without bending or dropping off. Is to provide a way.

According to the present invention, there is provided a method of manufacturing a mechanical splice of a sleeve method, wherein an electroformed body that has been electrodeposited by electroforming using a cathode rotating method has a high profile by processing the outer shape to a predetermined dimension and removing the core wire. It becomes a connecting part with an accurate connecting hole (hole diameter), and it is covered with different outer diameters by a fixing part for fixing a covering cord by caulking a soft metal pipe and an auxiliary fixing part for adjusting the inner diameter of the fixing part. There is provided a method of manufacturing a mechanical splice of a sleeve method that also supports cord fixing.

In the manufacturing method of the present invention, both ends of an optical fiber-shaped core wire having excellent roundness and surface shape are supported with a constant tension by a cathode rotation type electroforming as a connecting component, and straightened and rotated while rotating. Perform electrodeposition. The obtained cylindrical electroformed body is subjected to outer diameter grinding to a predetermined dimension, further cut and polished to a predetermined length, and the core wire is removed.

A wire centerless machine can be used for the apparatus for processing the outer periphery of the electroformed body with high accuracy.

Next, the fixing part uses a soft metal tube, and the length is cut to a length of about 10 mm to 20 mm at both ends from the connecting part and the length of the auxiliary fixing part joined to both ends of the connecting part. I will do it.

The auxiliary fixing part uses a metal tube and is cut to a length of 5 mm to 10 mm. The inner diameter of the fixing part is the outer diameter, and the outer diameter of the covering cord is the inner diameter. Will be included.

The connecting part is inserted into the inner diameter of the fixing part and is stored in the center position. Next, auxiliary connecting parts are inserted into the fixing part from one end of the fixing part and the other from the other end. A mechanical splice by the storage sleeve method.

In the manufacturing method of the present invention, the connection hole (hole diameter) of the electroformed body as the connection component is determined by the outer diameter of the core wire as the base material, and the accuracy of the connection hole (hole diameter) is also the outer diameter accuracy of the core wire. Determined by Therefore, in particular, with respect to the connecting parts for matching the optical fibers, the optical fiber has a similar cross section (true circle), has a slightly larger diameter than the optical fiber, and has high precision roundness and straightness. Using a core wire can provide a mechanical splice with extremely high connection hole (hole diameter) accuracy.

The core wire is preferably made of a material having rigidity to some extent so as not to be cut at the time of electroforming or removal of the core wire by drawing, such as a material used for piano wire, stainless steel Steel, special steel in which various elements are added to steel are suitable.

In the manufacturing method of the present invention, in order to remove the core wire from the above-described connecting component electroformed body, only the core wire may be dissolved from the electroformed body, or extruded or pulled out. Thereby, a cylindrical metal tube having a through hole corresponding to the cross-sectional shape of the core wire is obtained.

The mechanical splice manufacturing method, which is the sleeve method of the present invention, is excellent in roundness and surface shape, and a straight connection hole (hole diameter) enables low-loss optical transmission, and the optical fiber is firmly fixed. I was able to do it.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, although embodiment of the manufacturing method of this invention is described, this invention is not limited to this.

First, FIG. 3 shows an apparatus for manufacturing the mechanical splice of the present invention by electroforming. This will be described with reference to a schematic diagram of a cathode rotating type electroforming apparatus. The apparatus shown in FIG. 3 includes an electroforming bath 19, an electroforming liquid 5 filled in the tank, an electroforming liquid heater 18, an anode 6, and a cathode 7. The anode 6 is installed on a base 20 installed at the bottom of the electroformed bath 19. As will be described later, the cathode 7 is provided on a support jig, and the core wire stretched between the upper and lower ends of the support jig is electrically connected. The core wire installed on the support jig rotates about the core wire 9 as the central axis through the gears 16a (upper part) and 16b (lower part) when the drive motor 15 and the shaft 17 linked to the motor rotate. For the circulation and stirring, the electroforming liquid 5 is pulled up by the circulation pump 21 and sprayed from the spray nozzle 14 on the base 20 through the filtration tower 21.

The electroforming liquid 5 is determined according to the material of the metal to be electroformed around the core wire 9, for example, nickel or its alloy, iron or its alloy, copper or its alloy, cobalt or its alloy, tungsten alloy, fine particles Electroforming metals such as dispersed metals can be used, such as nickel sulfamate, nickel chloride, nickel sulfate, ferrous sulfamate, ferrous borofluoride, copper pyrophosphate, cobalt sulfate, copper sulfate, copper borofluoride, Liquids containing water-soluble components such as copper silicofluoride, copper copper fluoride, copper alkanol sulfonate, cobalt sulfate, sodium tungstate, etc., or silicon carbide, tungsten carbide, boron carbide, zirconium oxide, silicon nitride A liquid in which fine powders such as alumina and diamond are dispersed is used. Of these, a bath mainly composed of nickel sulfamate is suitable in terms of easiness of electroforming, low stress of the electrodeposit, chemical stability, ease of welding, and the like.

The electroforming liquid 5 is filtered using a felter with high filtration accuracy in an electroforming bath, and the temperature is controlled to an appropriate temperature range of about 50 ± 5 ° C. Further, it is sometimes preferable to remove the organic impurities by treating with activated carbon. In addition, it is possible to remove metal impurities such as copper from the electroforming liquid in the bath by using a nickel-plated iron corrugated sheet as a cathode and carbon as an anode at a low current density of about 0.2 A / dm ^2. desirable.

The anode 6 is selected according to the metal to be electroformed, and is selected from nickel, iron, copper, cobalt, etc., and a plate-like or spherical one can be used as appropriate. When using a spherical electrode, for example, it is placed in a titanium basket and covered with a polyester cloth bag.

FIG. 4 shows the support. Details will be described with reference to the schematic diagram of the support jig. (A) is a side view, (b) is a sectional view of the lower plate 13 as seen from the B-B ′ direction. In the support jig, an upper plate 12 and a lower plate 13 are connected via two support columns 11, and the upper plate 12 and the lower plate 13 are, for example, polyvinyl chloride resin, polyamide resin, polyacetylate resin, or polyethylene resin. The support 11 is made of a metal such as stainless steel or titanium, or a plastic. The upper plate 12 and the lower plate 13 are fixed to the support column 11 with screws. In the center of the upper plate 12, a stainless steel screw as the cathode 7 is provided so as to penetrate the upper plate 12. The stainless steel screw fixes one end 8 a of the stainless steel spring 8 on the lower surface of the upper plate 12. Similarly, a stainless screw 10 is provided at the center of the lower plate 13 so as to penetrate the lower plate 13 and protrude from the upper surface of the lower plate 13. One end 9 a of the core wire 9 is hooked on the other end 8 b of the stainless steel spring 8, and the other end 9 b is held by the stainless screw 10 while the spring 8 is extended by pulling both core wires. By attaching the core wire 9 to the support jig in this way, the core wire is supported in a state of being stretched straight in the vertical direction.

Returning to FIG. 3, the electroforming liquid is circulated and agitated by injecting the electroforming liquid from the ejection nozzle, circulating, and agitating. In addition, as a special case, the agitation is performed by ultrasonic irradiation. The stirring by is also effective.

The core wire 9 is made of a metal wire such as iron or an alloy thereof, aluminum or an alloy thereof, copper or an alloy thereof, a thin solder-plated metal wire, and a plastic wire such as nylon, polyester, or Teflon (registered trademark). Selected. Among these, in the case of plastic, it is assumed that it is a type of conductive plastic, and in the case of non-conductive, electroless plating such as conductive nickel or silver is required on the surface.

An operation of forming a tubular member by electroforming using the cathode rotary electroforming apparatus shown in FIG. 3 will be described. After the electroforming bath 20 is filled with the electroforming solution 5, the cathode 7 is rotated by the drive motor 15, and a DC voltage is applied to the anode 6 and the cathode 7 so as to obtain a current density of about 4 to 20 A / dm ^2. .

By the operation of the above-described cathode rotation type electroforming apparatus, metal is electrodeposited on the surface of the core wire 9 to a predetermined outer diameter.

After completion of electroforming, the support is taken out from the electroforming bath 19 and the core wire on which the electroformed body is formed is removed from the support jig.

As shown in FIG. 5, in the obtained electroformed body, an electroformed body 22 serving as an optical fiber connecting component is formed in a cylindrical shape with the core wire 9a and the core wire 9b exposed at both ends.

Next, the outer peripheral portion of the connection component electroformed body 22 is processed to have an outer diameter. A wire centerless machine is used for processing the outer periphery of the electroformed body.

For cutting the electroformed body, a thin blade cutter is used, and the electroformed body is cut into a predetermined length including a grinding allowance with respect to the longitudinal direction of the electroformed body, and both ends are polished to adjust the length. At this time, cutting and polishing are performed at right angles to the longitudinal direction of the electroformed body.

The method for removing the core wire can be performed by either extruding the core wire, drawing it out, or dissolving it with a chemical, but it may be determined based on the material of the selected core wire. In the case of a core wire having a high tensile strength, it is preferable to dissolve a wire that is easily dissolved in a chemical by using drawing. In this step, the core wire is pressed with a carbide pin, and the tip of the extruded core wire is picked and removed.

Moreover, if R-shaped countersinking is performed on both ends of the connection hole (hole diameter) of the connection component, the insertion property of the optical fiber is further improved.

The fixed part is manufactured using a commercially available metal tube, but since both ends are swaged, soft metals (aluminum, copper, stainless steel and alloys thereof) suitable for swaging are used.

Next, although it is an auxiliary | assistant fixed component, it can produce using a commercially available metal tube similarly to the said fixed component.

The fixed part and the auxiliary fixed part are each cut into a predetermined length including a grinding allowance using a thin blade cutter, and both ends are polished to adjust the length. At this time, cutting and polishing are performed in the longitudinal direction. It will be done at a right angle to it.

FIG. 6 shows a sectional view of a part of the mechanical splice of the sleeve method, which is the newly developed product. FIG. 6 (a) is a connection part 24 having a connection hole (hole diameter) 23, and FIG. A connecting component 24, a fixing component 25 having an inner diameter 26 for accommodating the auxiliary fixing component, and an auxiliary fixing component 27 having an inner diameter 28 for accommodating the covering cord portion are shown in FIG.

Next, FIG. 7 shows a mechanical splice sectional view 29 of the sleeve method integrated. The connection component 24 is inserted into the fixed component inner diameter 26 and accommodated at the center position, and further is an auxiliary fixed component 27. One is press-fitted from one end of the fixed component and the other is press-fitted from the other end. I will keep it.

The mechanical splice obtained in the above process is a caulking coated cord so that the optical fiber is inserted and abutted from both ends of the mechanical splice as shown in FIG. To fix.

The connecting procedure is to remove the coating on the ends of the two optical fiber coating cords, wipe the optical fiber with alcohol, and then cut the end surface into a mirror surface with a cutter. Next, both ends of the fixing component are added to the connection hole (hole diameter) of the connecting component into which the matching agent has been injected, with the optical fiber inserted and abutted from both ends through the inner diameter of the fixing component and the auxiliary fixing component. By tightening, the optical fiber covering cord is fixed, and the optical fiber is firmly fixed without bending or dropping off. Moreover, it is possible to realize a safe and reliable optical fiber connection with extremely low connection loss.

It is the exploded sectional view showing the general sleeve method mechanical splice. (A) Connection part sectional view (b) Fixed part sectional view It is the cross section which showed the general sleeve method mechanical splice. It is the schematic which showed the cathode rotating system electroforming apparatus. It is the schematic which showed the support jig. (A) Side view (b) Cross section It is the figure which showed the connection component electroformed body. It is sectional drawing which showed the sleeve method mechanical splice component. (A) Cross-sectional view of connecting parts (b) Cross-sectional view of fixed parts (c) Cross-sectional view of auxiliary fixed parts It is sectional drawing which showed the sleeve method mechanical splice integrated. It is sectional drawing which showed the optical fiber connection of the sleeve method mechanical splice.

Explanation of symbols

1 Connection component 2 Connection hole (hole diameter)
3 Inner Diameter 4 Fixed Parts 5 Electroforming Liquid 6 Anode 7 Cathode 8 Stainless Spring 8a One End of Stainless Spring 8b Other End of Stainless Spring 9 Core Wire (Connecting Parts Base Material)
9a One end of the core wire (base material for connecting parts)
9b The other end of the core wire (base material for connecting parts)
10 Stainless steel screw 11 Post 12 Upper plate 13 Lower plate 14 Nozzle for injection 15 Drive motor 16a Gear (upper part)
16b Gear (lower part)
17 Shaft 18 Heating heater 19 Electroformed bathtub 20 Base 21 Filtration tower and circulation pump 22 Connection part Electroformed body 23 Mechanical splice connection part connection hole 24 Mechanical splice connection part 25 Mechanical splice fixation part 26 Mechanical splice fixation part inner diameter 27 Mechanical splice auxiliary Fixed component 28 Mechanical splice auxiliary fixed component inner diameter 29 Mechanical splice diagram of integrated sleeve method 30 Sleeve method mechanical splice optical fiber connection diagram

Claims (6)

Cylindrical connecting parts with optical fiber connection holes (hole diameters), tube-shaped coated cord fixing parts (hereinafter referred to as fixed parts) having crimped portions at both ends, and pipe-shaped receiving parts Constructed by auxiliary fixing parts, the connecting parts support the core wire in the shape of optical fiber with high roundness straightly, and are produced by metal electro-deposited cylindrical electroformed body by cathode rotating method electroforming method A method of manufacturing a mechanical splice characterized by: The electroformed body is characterized in that a cylindrical body having an outer diameter and a length processed to a predetermined dimension, and a base material core wire removed to form an optical fiber connection hole (hole diameter) is used as a connection part. A method for producing a mechanical splice according to 1. The fixing component is a soft component that requires a connecting component at the longitudinal center position of the inner diameter of the fixing component, an auxiliary fixing component adjacent to both ends of the connecting component, and a covering cord caulking fixing portion having a length of about 10 to 20 mm at both ends. 2. The method of manufacturing a mechanical splice according to claim 1, wherein the mechanical splice is a metal tube (aluminum, copper, stainless steel and alloys thereof). The auxiliary fixing part is a jig that press-fits both ends of the fixing part and stores the covering cord, and is a metal tube having a length of about 5 to 10 mm, an inner diameter of the fixing part being an outer diameter, and an outer diameter of the covering cord being an inner diameter. The method for producing a mechanical splice according to claim 1, wherein: 5. The method of manufacturing a mechanical splice according to claim 1, wherein the metal is one selected from the group consisting of aluminum, nickel, iron, copper, cobalt, tungsten, and alloys thereof. A method for manufacturing a mechanical splice, which is manufactured by the manufacturing method according to claim 1.

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