JP3887576B2 - Optical fiber introduction part sealing method and optical fiber sealing member used therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical fiber introduction portion sealing method and an optical fiber sealing member used therein, and in particular, an optical fiber introduction portion sealing method applied to an optical submarine repeater and a low melting point metal used therein. It is related with the made optical fiber sealing member.
[0002]
[Prior art]
An optical submarine repeater is an optical submarine cable repeater used on the seabed in an optical communication system. The optical submarine repeater will be described. As shown in FIG. 12, the relay circuit 4, which is the main component of the optical submarine repeater, is surrounded by the heat dissipation buffer 3 and the pressure-resistant housing 1. The pressure-resistant housing 1 has a cylinder 2 and an end face plate 5.
[0003]
The optical fiber in the optical submarine cable is connected to the relay circuit 4 from the tail cable 7 through the feedthrough 6 provided on the end face plate 5. An optical fiber introduction sealing portion is disposed in the feedthrough 6.
[0004]
Next, the optical fiber introduction sealing part will be described. As shown in FIG. 13, in the conventional optical fiber introduction sealing part 110, the fiber guide 112 for arranging and arranging the some optical fiber 111 is provided. A sleeve 113 is provided around the fiber guide 112 and the optical fiber 111. The fiber guide 112 is fixed to the sleeve 113 by a nut 115.
[0005]
A gap (space) between the sleeve 113 and the fiber guide 112 is filled with a low melting point metal member 114 as a sealing member. The low melting point metal member 114 is made of, for example, solder.
[0006]
Further, the surface of the optical fiber 111 is covered with a metal coating portion 118 in order to improve the adhesion between the low melting point metal member 114 and the optical fiber 111. The metal coating portion 118 is formed on the surface of the optical fiber 111 by, for example, vapor deposition. The inside of the dashed-dotted line 120 is the main part in the optical fiber introduction sealing part.
[0007]
Next, a method for sealing the optical fiber introduction sealing portion 110 will be described. As shown in FIG. 14, first, a predetermined number of optical fibers 111 are aligned and arranged around the fiber guide 112. Next, the fiber guide 112 is fixed to the sleeve 113 with a nut (not shown).
[0008]
Further, as shown in FIG. 15, a rod-shaped low melting point metal member 130 is disposed between the optical fiber 111 and the optical fiber 111 in the gap (space) between the sleeve 113 and the fiber guide 112. At this time, the optical fiber 111 and the low melting point metal member 130 are alternately arranged around the fiber guide 112.
[0009]
Next, for example, the low melting point metal member 130 is heated by the heating device 140 using high frequency to melt the low melting point metal member 130 and then cooled. As a result, as shown in FIG. 16, the low melting point metal member 130 is filled in the gap (space) between the sleeve 113 and the fiber guide 112 to form the sealing member 114. At this time, a ridge-like fillet portion (inside the one-dot chain line 135) is formed in the sealing member 114 from the upper end portion of the sleeve 113 toward the fiber guide 112.
[0010]
By forming the ridged fillet portion, the stress load on the optical fiber 111 by the sealing member 114 is alleviated, and the reduction in the performance of the optical fiber 111 is suppressed.
[0011]
In this way, an optical fiber introduction sealing portion is formed. The completed optical fiber introduction sealing portion is arranged in the feedthrough 6 (see FIG. 12).
[0012]
[Problems to be solved by the invention]
However, the conventional method for sealing an optical fiber introduction sealing portion has the following problems. In order to fill the gap (space) between the sleeve 113 and the fiber guide 112 with a low melting point metal member as a sealing member and to form a ridged fillet portion (inside the one-dot chain line 135), a relatively long rod-shaped low A melting point metal member 130 is required.
[0013]
When heating such a relatively long rod-shaped low-melting-point metal member 130, as shown in FIG. 17, the portion of the low-melting-point metal member 130 located above the gap between the sleeve 113 and the fiber guide 112 is formed. In some cases, the sleeve 113 may be inclined toward the outer periphery 180.
[0014]
For this reason, the low melting point metal member 130 melts from the middle portion, and the fillet portion may not be satisfactorily formed in a mountain-shaped shape as shown in FIG. 18 (inside the one-dot chain line 136). Further, the fillet portion may not be formed uniformly in the circumferential direction of the sealing member 114. As a result, the stress load on the optical fiber 111 due to the sealing member 114 is not relaxed, and the performance of the optical fiber 111 may be deteriorated.
[0015]
The present invention has been made to solve the above-mentioned problems, and one object is to provide an optical fiber introduction portion sealing method in which a fillet portion is well formed, and the other object is to do so. It is providing the optical fiber sealing member used for the optical fiber introducing | transducing part sealing method.
[0016]
[Means for Solving the Problems]
An optical fiber introduction portion sealing method according to one aspect of the present invention includes the following steps. The optical fiber is aligned and held along the circumference of the fiber guide having the circumference. The fiber guide and the optical fiber held by the fiber guide are surrounded from the circumferential direction, and a cylindrical sleeve is disposed in which the upper end side is opened and the lower end side is closed in the surrounded state. A first metal member having a predetermined length is disposed along a peripheral portion of the fiber guide in a region where the optical fiber is disposed between the sleeve and the fiber guide. A ring-shaped second metal member is disposed at the upper end of the sleeve so as to surround the fiber guide and the optical fiber held by the fiber guide from the circumferential direction. The first metal member and the second metal member are melted by heat treatment to fill a region sandwiched between the sleeve and the fiber guide, and the fiber guide is positioned above the upper end portion of the sleeve from the upper end portion thereof. A sealing member for sealing the portion of the optical fiber located between the sleeve and the fiber guide is formed by extending in a ridge shape toward this portion.
[0017]
According to this method, when forming the sealing member by melting the first metal member and the second metal member, the first metal member is melted so as to fill a gap (space) between the sleeve and the fiber guide. On the other hand, the second metal member melts so as to fill the inside of the ring-shaped second metal member. As a result, the second metal member does not melt down in the outer circumferential direction of the sleeve, and a desired ridged fillet portion is stably formed from the upper end of the sleeve to the fiber guide. As a result, the stress load on the optical fiber by the sealing member can be reliably relaxed, and the performance of the optical fiber can be prevented from deteriorating.
[0018]
In the step of arranging the second metal member, it is preferable to use a ring-shaped second metal member having an outer diameter shorter than the outer diameter of the sleeve.
[0019]
In this case, when the second metal member is melted, it is melted so as to reliably fill the inside of the ring-shaped second metal member. Therefore, it is possible to prevent the second metal member from melting in the outer peripheral direction of the sleeve.
[0020]
Moreover, it is preferable to provide the process of arrange | positioning the ring-shaped member for surrounding the 2nd metal member from the circumferential direction in the said upper end part of a sleeve before the process of forming a sealing member.
[0021]
Thereby, when the second metal member is melted, it is reliably prevented from melting in the outer circumferential direction of the sleeve.
[0022]
Further, in the step of arranging the second metal member, it is preferable to use a taper-shaped second metal member having an outer diameter that decreases upward.
[0023]
Thereby, when the second metal member is melted, the ring-shaped second metal member is surely melted inward.
[0024]
An optical fiber sealing member according to another aspect of the present invention is located in a region sandwiched between a fiber guide and a cylindrical sleeve disposed so as to surround the fiber guide from the circumferential direction, and is disposed at a peripheral portion of the fiber guide. An optical fiber sealing member for sealing an optical fiber by melting the optical fiber aligned and held along the optical fiber, and includes a first metal member and a ring-shaped second metal member. . The first metal member is disposed in a region where the optical fiber is located between the fiber guide and the sleeve. The ring-shaped second metal member is disposed on the upper end side of the sleeve so as to surround the fiber guide and the optical fiber from the circumferential direction. The first metal member is fixed to the second metal member.
[0025]
According to this structure, when the first metal member and the second metal member are melted to seal the optical fiber, the first metal member is melted so as to fill a gap between the sleeve and the fiber guide, In particular, the second metal member melts so as to fill the inside of the ring-shaped second metal member. As a result, the second metal member does not melt down in the outer circumferential direction of the sleeve, and a desired ridged fillet portion is stably formed from the upper end of the sleeve to the fiber guide. As a result, the stress load on the optical fiber can be reliably relaxed, and the performance of the optical fiber can be prevented from deteriorating. And since the 1st metal member is being fixed to the 2nd metal member, the 1st metal member and the 2nd metal member can be easily arranged in a predetermined position, respectively.
[0026]
The second metal member is preferably tapered so that the outer diameter decreases upward.
[0027]
Thus, when the second metal member is melted, the second metal member is melted so as to reliably fill the inside of the ring-shaped second metal member. Therefore, it is possible to prevent the second metal member from melting in the outer peripheral direction of the sleeve.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
An optical fiber introduction portion sealing method according to Embodiment 1 of the present invention and an optical fiber sealing member used therefor will be described. As shown in FIG. 1, first, a predetermined number of optical fibers 11 are aligned and arranged around the fiber guide 12. Next, the fiber guide 12 is fixed to the sleeve 13 with a nut (not shown).
[0030]
Further, as shown in FIG. 2, a rod-shaped low melting point metal member 31 is disposed between the optical fiber 11 and the optical fiber 11 in the gap (space) between the sleeve 13 and the fiber guide 12. At this time, the optical fiber 11 and the low melting point metal member 31 are alternately arranged around the fiber guide 12.
[0031]
Then, a ring-shaped low melting point metal member 32 is disposed on the upper end portion of the sleeve 13. The outer diameter of the ring-shaped low melting point metal member 32 is preferably smaller than the outer diameter of the sleeve 13.
[0032]
Next, the low melting point metal members 31 and 32 are heated and melted by, for example, a heating device 40 using high frequency. In this heating and melting process, the low melting point metal member 31 is spent filling the gap (space) between the sleeve 13 and the fiber guide 12. On the other hand, the low melting point metal member 32 is expended to form a ridged fillet portion extending from the upper end portion of the sleeve 13 in the longitudinal direction of the fiber guide 12.
[0033]
At this time, since the outer diameter of the ring-shaped low-melting-point metal member 32 is smaller than the outer diameter of the sleeve 13, when the low-melting-point metal member 32 is melted, as shown by an arrow 81 in FIG. The low melting point metal member 32 is melted so as to fill the inside. Therefore, it does not melt down in the outer peripheral direction of the sleeve 13.
[0034]
As a result, as shown in FIG. 4, a desired ridged fillet portion (inside the one-dot chain line 35) is stably formed from the upper end portion of the sleeve 13 to the fiber guide 12. As a result, the stress load on the optical fiber 11 due to the sealing member 14 formed by melting the low melting point metal member is surely relaxed, and the performance of the optical fiber 11 can be prevented from deteriorating.
[0035]
In the optical fiber introduction portion sealing method described above, the low-melting-point metal member 31 disposed between the optical fiber 11 and the optical fiber 11 as the low-melting-point metal member, and the upper end of the sleeve 13 are disposed. The case where the ring-shaped low-melting-point metal member 32 is separated is described as an example.
[0036]
In addition, as shown in FIG. 5, an integrated low-melting-point metal member 30 in which a rod-shaped low-melting-point metal member 31 is fixed in advance to a ring-shaped low-melting-point metal member 32 may be applied. In this case, the trouble of arranging the rod-like low melting point metal members 31 one by one at a predetermined position can be saved.
[0037]
Embodiment 2
An optical fiber introduction portion sealing method according to Embodiment 2 of the present invention will be described. As shown in FIG. 6, first, a predetermined number of optical fibers 11 are aligned and arranged around the fiber guide 12. Next, the fiber guide 12 is fixed to the sleeve 13 with a nut (not shown).
[0038]
Further, as shown in FIG. 7, a rod-shaped low melting point metal member 31 is disposed between the optical fiber 11 and the optical fiber 11 in the gap (space) between the sleeve 13 and the fiber guide 12. At this time, the optical fiber 11 and the low melting point metal member 31 are alternately arranged around the fiber guide 12.
[0039]
A burn-off prevention ring member 50 is disposed on the outer peripheral portion of the sleeve 13 to prevent the ring-shaped low melting point metal member 32 from melting toward the outer periphery. As the melt-off preventing ring member 50, for example, Kapton (R) tape or Teflon (R) tape having heat resistance is preferable.
[0040]
Next, the low melting point metal members 31 and 32 are heated and melted by, for example, a heating device 40 using high frequency. In this heating and melting process, the low melting point metal member 31 is spent filling the gap (space) between the sleeve 13 and the fiber guide 12. On the other hand, the low melting point metal member 32 is expended to form a ridged fillet portion extending from the upper end portion of the sleeve 13 in the longitudinal direction of the fiber guide 12.
[0041]
At this time, the melt-off prevention ring member 50 is provided, so that when the low-melting-point metal member 32 melts, the melt-down in the outer circumferential direction of the sleeve 13 is reliably prevented.
[0042]
As a result, as shown in FIG. 4 described above, a desired ridged fillet portion is stably formed from the upper end portion of the sleeve 13 to the fiber guide 12. As a result, the stress load on the optical fiber 11 due to the sealing member 14 formed by melting the low melting point metal member is surely relaxed, and the performance of the optical fiber 11 can be prevented from deteriorating.
[0043]
Embodiment 3
An optical fiber introducing portion sealing method and a sealing member used therefor according to Embodiment 3 of the present invention will be described. As shown in FIG. 8, first, a predetermined number of optical fibers 11 are aligned and arranged around the fiber guide 12. Next, the fiber guide 12 is fixed to the sleeve 13 with a nut (not shown).
[0044]
Further, as shown in FIG. 9, a rod-shaped low melting point metal member 31 is disposed between the optical fiber 11 and the optical fiber 11 in the gap (space) between the sleeve 13 and the fiber guide 12. At this time, the optical fiber 11 and the low melting point metal member 31 are alternately arranged around the fiber guide 12.
[0045]
A ring-shaped and tapered low melting point metal member 33 is disposed at the upper end of the sleeve 13. The outer diameter of the tapered low melting point metal member 33 is preferably smaller than the outer diameter of the sleeve 13.
[0046]
Next, for example, the low melting point metal members 31 and 33 are heated and melted by the heating device 40 using high frequency. In this heating and melting process, the low melting point metal member 31 is spent filling the gap (space) between the sleeve 13 and the fiber guide 12. On the other hand, the low melting point metal member 33 is consumed to form a ridged fillet portion extending from the upper end portion of the sleeve 13 in the longitudinal direction of the fiber guide 12.
[0047]
At this time, the outer diameter of the low melting point metal member 33 is smaller than the outer diameter of the sleeve 13 and the low melting point metal member 33 is tapered, so that when the low melting point metal member 33 is melted, the low melting point metal member 33 has a low melting point. The metal member 33 is surely melted inward.
[0048]
As a result, as shown in FIG. 4, a desired ridged fillet portion is stably formed from the end of the sleeve 13 to the fiber guide 12. As a result, the stress load on the optical fiber 11 due to the sealing member 14 formed by melting the low melting point metal member is surely relaxed, and the performance of the optical fiber 11 can be prevented from deteriorating.
[0049]
In the optical fiber introduction portion sealing method described above, the rod-shaped low melting point metal member 31 disposed between the optical fiber 11 and the optical fiber 11 as the low melting point metal member, and the end of the sleeve 13 are disposed. The case where the taper-shaped low melting point metal member 33 is separated is described as an example.
[0050]
In addition, as shown in FIGS. 10 and 11, an integrated low-melting-point metal member 30 in which a rod-shaped low-melting-point metal member 31 is fixed in advance to a tapered low-melting-point metal member 33 may be applied. In this case, the trouble of arranging the rod-like low melting point metal members 31 one by one at a predetermined position can be saved.
[0051]
Further, in each of the above embodiments, the optical fiber introduction part used for the submarine repeater has been described as an example of the optical fiber introduction part sealing method. However, the present invention is not limited to the submarine repeater, and the apparatus has the optical fiber introduction part. It is possible to apply to.
[0052]
The embodiment disclosed this time is to be considered as illustrative in all points and not restrictive. The present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[0053]
【The invention's effect】
According to the optical fiber introduction portion sealing method in one aspect of the present invention, when the first metal member and the second metal member are melted to form the sealing member, the first metal member includes the sleeve and the fiber guide. The second metal member is melted so as to fill the inside of the ring-shaped second metal member. As a result, the second metal member does not melt down in the outer circumferential direction of the sleeve, and a desired ridged fillet portion is stably formed from the upper end of the sleeve to the fiber guide. As a result, the stress load on the optical fiber by the sealing member can be reliably relaxed, and the performance of the optical fiber can be prevented from deteriorating.
[0054]
In the step of arranging the second metal member, it is preferable to use a ring-shaped second metal member having an outer diameter shorter than the outer diameter of the sleeve. In this case, the second metal member melts. In this case, melting is performed so as to reliably fill the inside of the ring-shaped second metal member. Therefore, it is possible to prevent the second metal member from melting in the outer peripheral direction of the sleeve.
[0055]
Moreover, it is preferable to provide a step of arranging a ring-shaped member for surrounding the second metal member from the circumferential direction at the upper end portion of the sleeve before the step of forming the sealing member. When the second metal member is melted, it is reliably prevented from melting in the outer circumferential direction of the sleeve.
[0056]
In the step of arranging the second metal member, it is preferable to use a ring-shaped second metal member having a tapered shape whose outer diameter becomes smaller upward, whereby the second metal member is melted. At this time, the ring-shaped second metal member surely melts inward.
[0057]
According to the optical fiber sealing member in another aspect of the present invention, when the first metal member and the second metal member are melted to seal the optical fiber, the first metal member is formed between the sleeve and the fiber guide. While melting to fill the gap, the second metal member in particular melts to fill the inside of the ring-shaped second metal member. As a result, the second metal member does not melt down in the outer circumferential direction of the sleeve, and a desired ridged fillet portion is stably formed from the upper end of the sleeve to the fiber guide. As a result, the stress load on the optical fiber can be reliably relaxed, and the performance of the optical fiber can be prevented from deteriorating. And since the 1st metal member is being fixed to the 2nd metal member, the 1st metal member and the 2nd metal member can be easily arranged in a predetermined position, respectively.
[0058]
The second metal member preferably has a tapered shape with an outer diameter that decreases upward, so that when the second metal member is melted, the inner side of the ring-shaped second metal member is surely secured. Melt to fill. Therefore, it is possible to prevent the second metal member from melting in the outer peripheral direction of the sleeve.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a step of an optical fiber introduction portion sealing method according to Embodiment 1 of the present invention.
2 is a cross sectional view taken along a section line II-II in the step shown in FIG. 1 in the embodiment. FIG.
3 is a longitudinal sectional view showing a process performed after the process shown in FIG. 1 in the embodiment. FIG.
4 is a longitudinal sectional view showing a process performed after the process shown in FIG. 3 in the embodiment. FIG.
FIG. 5 is a perspective view showing an example of a low melting point metal member in the embodiment.
FIG. 6 is a longitudinal sectional view showing one step of the optical fiber introduction portion sealing method according to Embodiment 2 of the present invention.
7 is a transverse sectional view taken along a section line VII-VII in the step shown in FIG. 6 in the embodiment. FIG.
FIG. 8 is a longitudinal sectional view showing one step of an optical fiber introduction portion sealing method according to Embodiment 3 of the present invention.
9 is a transverse sectional view taken along a sectional line IX-IX in the step shown in FIG. 8 in the embodiment. FIG.
FIG. 10 is a perspective view showing an example of a low melting point metal member in the embodiment.
11 is a cross-sectional view of the low melting point metal member taken along a cross-sectional line XI-XI shown in FIG. 10 in the embodiment.
FIG. 12 is a cross-sectional view of an optical submarine repeater.
FIG. 13 is a longitudinal sectional view of a conventional optical fiber introduction sealing portion used for an optical submarine repeater.
FIG. 14 is a longitudinal sectional view showing one process of a conventional optical fiber introduction portion sealing method.
15 is a transverse sectional view in the step shown in FIG. 14. FIG.
16 is a longitudinal sectional view showing a step performed after the step shown in FIG.
FIG. 17 is a longitudinal sectional view showing one process for explaining a problem of a conventional optical fiber introduction portion sealing method.
FIG. 18 is a longitudinal sectional view showing another process for explaining a problem of the conventional optical fiber introduction portion sealing method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pressure-resistant housing, 2 Cylinder, 3 Heat sink, 4 Relay circuit, 5 End face plate, 6 Feed through, 7 Tail cable, 11 Optical fiber, 12 Fiber guide, 13 Sleeve, 14 Sealing member, 18 Metal coating part, 30, 31, 32, 33 Low melting point metal member, 40 heating device, 50 burn-off prevention ring member.

Claims (6)

Aligning and holding the optical fiber along the circumference of the fiber guide having a circumference; and
A step of surrounding the optical fiber held by the fiber guide and the fiber guide from a circumferential direction, and disposing a cylindrical sleeve in which the upper end side is opened and the lower end side is closed in the enclosed state;
Disposing a first metal member having a predetermined length along the peripheral portion of the fiber guide in a region where the optical fiber is disposed between the sleeve and the fiber guide;
Disposing a ring-shaped second metal member at the upper end of the sleeve so as to surround the fiber guide and the optical fiber held by the fiber guide from the circumferential direction;
The first metal member and the second metal member are melted by performing a heat treatment and filled in a region sandwiched between the sleeve and the fiber guide, and the upper end portion of the sleeve is extended from the upper end portion. Forming a sealing member for sealing the portion of the optical fiber located between the sleeve and the fiber guide by extending in a ridge shape toward the portion of the fiber guide located above; ,
An optical fiber introduction part sealing method comprising:   2. The optical fiber introduction portion sealing method according to claim 1, wherein in the step of arranging the second metal member, a ring-shaped second metal member having an outer diameter shorter than an outer diameter of the sleeve is used.   The method according to claim 1, further comprising a step of arranging a ring-shaped member for surrounding the second metal member in a circumferential direction at the upper end portion of the sleeve before the step of forming the sealing member. The optical fiber introduction part sealing method as described.   4. The optical fiber according to claim 1, wherein in the step of arranging the second metal member, a ring-shaped second metal member having a tapered shape whose outer diameter decreases upward is used. Introduction part sealing method. For an optical fiber positioned in a region sandwiched between a fiber guide and a cylindrical sleeve disposed so as to surround the fiber guide from the circumferential direction, and aligned and held along the circumference of the fiber guide, An optical fiber sealing member for sealing the optical fiber by melting,
A first metal member disposed between the fiber guide and the sleeve and disposed in a region where the optical fiber is located;
A ring-shaped second metal member disposed on the upper end side of the sleeve so as to surround the fiber guide and the optical fiber from the circumferential direction ;
The optical fiber sealing member, wherein the first metal member is fixed to the second metal member.   The optical fiber sealing member according to claim 5, wherein the second metal member has a tapered shape with an outer diameter decreasing upward.

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