JP2001033673A - Water cut-off structure for cable hole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make improvable the durability of a pressing mechanism for maintaining a compressed condition of a water-stop packing, in a water cut-off structure for a cable hole provided in an optical fiber storing body requiring water-proofness such as a closure. SOLUTION: In this water cut-off structure for a cable hole, a compressive packing 24 arranged in the periphery of an optical cable 6 inserted into a cable hole 21a penetrated through a wall part 21 of an optical fiber storing body such as a closure is pressed from an inside of the optical fiber storing body to the wall part 21 around the cable hole 21a by a pressing mechanism 22, and it is compression-deformed thereby to seal the cable hole 21a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water blocking structure for a cable hole.

[0002]

2. Description of the Related Art For example, in manholes and handholes, and when laying optical cables overhead, a closure provided at a connection portion between optical cables needs to be particularly waterproof against an environment exposed to groundwater or wind and rain. . Above all, it is important to ensure waterproofness of the cable hole into which the optical cable is drawn, and various configurations have been realized.

FIGS. 10 (a) and 10 (b) are views showing a so-called pot type closure 1, where (a) is a front view,
(B) is a diagram viewed from arrow a in (a), and is a diagram showing the end face plate 2. In FIGS. 10A and 10B, the closure 1
Is designed to secure the inside waterproofness by closing the opening 4 of the cylindrical closure sleeve 3 with a bottom with the end face plate 2. As shown in FIG. 11, the optical cable 6 drawn into the inside of the closure 1 from the cable hole 5 formed in the end face plate 2 is held and fixed by the holding component 1a arranged inside the closure 1, and is exposed to the terminal. The tension member 6c thus fixed is fixed by the tension member fixing tool 1b arranged inside the closure 1. Further, an optical connection portion (not shown) of the optical fibers 7 and an extra length of the optical fibers 7 output from the terminal of the optical cable 6 are stored in a tray or the like disposed inside the closure 1. In FIG. 11,
Reference numeral 6b is a slot. As shown in FIGS. 10 (a) and 10 (b), the end face plate 2 is often in the shape of an undivided disk, and the waterproofness of the cable hole 5 is ensured by a water stop structure described later. The closure sleeve 3 is often formed in a cylindrical shape with a bottom that is not divided from resin, but a split structure or the like is also employed. The closure sleeve 3 having any structure is secured with waterproofness by being fastened to the end face plate 2 by the band 8.

FIGS. 11 and 12 show a conventional water-stop structure applied to the closure 1. FIG. As shown in FIGS. 11 and 12, in the conventional waterproof structure, a ring-shaped sealing washer 9 inserted through the optical cable 6 penetrating the cable hole 5 of the end face plate 2 is screwed from the outside of the closure 1 into a screw 10. The ring-shaped rubber packing 11 inserted into the optical cable 6 is pressed into the cable hole 5 to be compressed and deformed, thereby sealing the cable hole 5. The rubber packing 11 is inserted from the outside of the closure 1 into a packing hole 5a having a shape in which a portion of the cable hole 5 located outside the closure 1 is expanded, and a bearing, which is a step between the packing hole 5a and the cable hole 5, is provided. The packing hole 5 a is sealed by being sandwiched between the wall 12 and the sealing washer 9 and compressed and deformed, so that the waterproofness of the cable hole 5 is ensured.

[0005]

However, in the above waterproof structure, the end plate 2 is fixed with the screws 10 from the outside of the closure 1, so that the screws 10 exposed on the outside of the closure 1 are easily corroded. This has led to a shortened life of the closure 1 and a shortened maintenance and inspection cycle. In order to prevent corrosion of the screw 10, measures such as attaching a waterproof cap to the screw 10 are conceivable. However, a cap which does not easily separate from the screw 10 and which can ensure the waterproofness can be provided individually. If this is done, the cost will increase and the time required for assembling the closure 1 will be prolonged. The above problem is not limited to the pot type closure, but is common to various closures to which the above-described water blocking structure is applied. Also, besides closures,
For example, various optical fiber containers such as an optical connection box and an optical branching box need to be solved because the same problem occurs in the water blocking structure of the cable hole.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and is an optical fiber container provided in a manhole, a handhole, an optical cable laid overhead, etc., which can reliably maintain excellent waterproofness for a long period of time. It is intended to provide a water blocking structure for holes.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a water blocking structure for a cable hole in an optical fiber housing for housing an optical connection portion between optical fibers drawn from an optical cable and an optical component such as an extra length. A compressible packing disposed around an optical cable inserted into a cable hole passing through a wall of the optical fiber container, and pressing the packing against the wall around the cable hole from inside the optical fiber container. And a pressing mechanism for compressing and deforming the cable hole to seal the cable hole. According to this water stopping structure, since the compressive deformation of the packing by the pressing mechanism is performed from the inside of the optical fiber housing, the pressing mechanism has no portion exposed to the outside of the optical fiber housing. As the pressing mechanism,
In order to generate the pressing force of the packing, there is a demand to use a metal part having excellent strength, for example, but there is no need to worry about corrosion of the constituent parts if the structure is not exposed to the outside of the optical fiber container as described above. It is not necessary to take measures such as the use of components made of a material having excellent corrosion resistance, and it is possible to use components made of a general material such as steel.

In the present invention, it is more preferable to adopt the following configuration. According to a second aspect of the present invention, in the water blocking structure for a cable hole according to the first aspect, the pressing mechanism includes a screw screwed to a cable gripping part that grips and fixes the optical cable near the cable hole. And a pressing member driven by a rotation operation of the screw to press the packing toward a wall around the cable hole. According to a third aspect of the present invention, in the water blocking structure of the cable hole according to the second aspect, the rotation operation of the screw can be performed from a side substantially orthogonal to an axial direction of the optical cable gripped and fixed to the cable gripping component. It is characterized by having become.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A water blocking structure for a cable hole according to an embodiment of the present invention will be described below with reference to FIGS. In the drawings, the same components as those in FIGS. 10 to 12 are denoted by the same reference numerals, and description thereof will be simplified.

FIG. 1 shows a closure 20 which is an optical fiber housing to which a water blocking structure for a cable hole according to the present invention is applied.
FIG. 4 is a view showing the internal structure of a (pot-shaped closure),
(A) is a plan view and (b) is a front view. FIG. 1 (a),
In (b), the disc-shaped end face plate 21 is disposed so as to close the opening 4 of the closure sleeve 3, and the band 8 (FIG. 1) is provided near the opening 4 of the closure sleeve 3.
Not shown in (a) and (b). It is fixed by tightening according to FIG. The band 8 can be tightened and fixed and the tightening force can be released by operating the tying tool 8a. When the tightening force of the band 8 is released, the end face plate 21 can be removed from the closure sleeve 3. The end face plate 21 corresponds to the wall of the optical fiber container, which is the closure 20, and has a cable hole 21 a through which the optical cable 6 is drawn through the closure 20.

1 (a) and 1 (b), a waterproof structure for a cable according to the present embodiment comprises a packing 24 disposed around the optical cable 6 inserted into the cable hole 21a.
And a pressing mechanism 22 that presses the packing 24 from the inside of the closure 20 to the end face plate 21 (specifically, the supporting wall 26) around the cable hole 21 a and compresses and deforms the packing 24. The packing 24 is brought into close contact with the periphery of the optical cable 6 so that the cable hole 21 is formed.
a is sealed. Specifically, FIG.
As shown in (a) and (b), the packing 24 is housed in a packing hole 25 in which a portion of the cable hole 21a facing the inside of the closure 1 is expanded.
It is compressed and deformed by being sandwiched between the supporting wall 26 which is a step between the cable hole 21a and the pressing member 23 (sealing washer). Packing 24 outer diameter is packing hole 2
Since the packing 24 substantially matches the inside diameter, the packing 24 comes into close contact with the inner surface of the packing hole 25 and the periphery (outer surface) of the optical cable 6 due to compression deformation, and seals the cable hole 21a.

FIG. 2 shows an example of the packing 24. FIG.
The packing 24 has a structure in which a ring-shaped packing body 24a made of an elastomer is sandwiched from both sides in the axial direction by a ring-shaped washer 24b made of an elastically deformable resin such as plastic. The packing body 24a and the washers 24b on both sides are arranged on the same axis, and the packing body 24a and the washer 24b are fixed by bonding or the like. The packing body 24
a and the washer 24b have the same outer diameter, and there is no step on the outer surface of the packing 24 between the packing body 24a and the washer 24b. Note that the packing body 24a itself also functions as a packing constituting the waterproof structure according to the first aspect. Various elastomers such as EPDM (a copolymer obtained by adding a small amount of a non-conjugated diene to ethylene-propylene rubber; DM is an abbreviation of a diene monomer) can be used as the elastomer constituting the packing body 24a.

The packing 24 is divided into two parts so that the packing halves 24d and 24e on both sides in the circumferential direction can be opened and closed around a thin connecting portion 24c formed on the washer 24b. Each packing half 24d,
The ring-shaped packing 24 is assembled by engaging the engaging portions 24f and 24g at the distal end farthest from the thin connecting portion 24c of 24e. Referring to FIG.
f and 24g are in the form of claws formed with a washer 24b. A number of ribs 24h are provided on the inner surface side of the washer 24b.
Is protruding. The protruding tips of the ribs 24h are substantially aligned with the inner surface of the packing body 24a. Since the ribs 24h serve a positioning function when the packing 24 is mounted on the optical cable 6 from outside, the packing 24 is arranged and mounted substantially coaxially without being unevenly distributed with respect to the optical cable 6. This packing 24 is
It is assembled in a ring shape around the optical cable 6 on the inner side of the end face plate 21 on the inside, and is inserted into the packing hole 24. It should be noted that the packing 24 having the split structure has excellent workability in mounting to the optical cable 6 as compared with a ring-shaped packing which cannot be divided in the circumferential direction. Also, in this water stop structure,
After inserting the optical cable into the cable hole, it is only necessary to place packing around the optical cable at a position inside the optical fiber housing, so even if it is a ring-shaped packing that cannot be divided in the circumferential direction, It can be easily attached by inserting from the end of the inserted optical cable,
There is no need to insert the packing into the optical cable before inserting it into the cable hole, and even after inserting the optical cable into the cable hole, it is easy to select and replace the packing to be used according to the cable diameter etc. Can be.

[0014] As shown in FIG.
The packing body 24a of the packing 24 sandwiched between the supporting wall 26 and the pressing member 23 is compressed and deformed so as to reduce the inner diameter, and the ribs 2 of the washers 24b on both sides are formed.
It protrudes inward from the front end for 4 h and closely adheres to the periphery of the optical cable 6 without any gap. In the vicinity of the optical cable 6, the packing body 24a deformed so as to reduce the inner diameter is pressed between the ribs 24h of the washers 24b on both sides, and the packing 2
Because the deformation that spreads to both sides in the axial direction of 4 is regulated,
The deformed packing body 24a can be efficiently brought into close contact with the periphery of the optical cable 6.

The pressing mechanism 22 includes a screw 28 screwed to a cable holding part 27 for holding and fixing the optical cable 6 in the vicinity of the cable hole 6, and the packing 24 is driven by rotating the screw 28. And a pressing member 23 for pressing the end face plate 21 (specifically, the supporting wall 26) around the cable hole 21a. The cable gripping component 27 is fixed to the end face plate 21 by a fixture such as a screw 29. The screw 28 can press the pressing member 23 toward the end face plate 21 by taking a reaction force to the cable gripping component 27. It has become. Further, when the screw 28 is rotated in the direction opposite to the case where the pressing member 23 is pressed in the direction of the end face plate 21, the screw 28 can be moved in the direction away from the end face plate 21 and the pressing force can be released. The pressing member 23 may be separated from the screw 28,
It is more preferable that the end plate 21 is integrally connected to the end plate 21 so as to be separated therefrom.

The operation of rotating the screw 28 can be performed from a side substantially orthogonal to the axial direction of the optical cable 6 gripped and fixed to the cable gripping component 27. FIG. 3 shows an example of the screw 28. A screw 28 shown in FIG. 3 is attached to a tool engaging portion 28a formed at a tip exposed from the cable gripping component 27 to a portion inside the closure 20.
The rotation operation is performed by engaging 0, 31. Tool engaging part 28
a is formed with a groove 28b extending perpendicularly to the axial direction of the screw 28. A tool 30 can be inserted through a portion of the groove 28b which is opened through the side of the tool engaging portion 28a. The screw 28 can be rotated by operating the tool 30 inserted in the groove 28b around the screw 28 axis. Since the rotation operation of the screw 28 by the tool 30 is performed from the side substantially orthogonal to the axial direction of the optical cable 6 (see FIG. 8), various members in the closure 20 and the optical fiber drawn out from the end of the optical cable 6 are used. 7 (mainly a single-core or multi-core optical fiber) and the like can be performed efficiently. The tool 31 can also be inserted into the groove 28b from outside in the axial direction of the screw 28, and the screw 28 can be rotated by rotating the tool 31 inserted into the groove 28b. Since the rotation operation of the screw 28 by the tool 31 can be continuously and rapidly performed, the closure 20
In the case where there is no problem of interference with the various members therein, the optical fiber 7 exiting from the end of the optical cable 6, and the like, rotating the screw 28 with the tool 31 can shorten the working time.

In FIG. 3 and the like, a tool engaging portion 28a formed with a groove 28b for inserting a tool is illustrated, but the tool engaging portion is not limited to this. And at least one pair of flat surfaces that can be engaged with each other, and a hole into which a rod-shaped tool can be inserted from the outside in the screw axis direction can be adopted. Further, the formation position of the tool engagement portion in the screw is not limited to the axial end portion as shown in FIG. 3 and may be any portion that can be exposed in a state where the closure sleeve 3 is not attached. Alternatively, the position may be such that it is exposed in a gap between the cable gripping component 27 and the end face plate 21.

On the other hand, as the pressing member 23, in FIG. 5 and the like, a rhombic plate-shaped sealing washer is employed. The pressing member 23 is housed in a pressing member housing hole 35 having an expanded end facing the inside of the closure 20 of the packing hole 25. Note that various shapes can be adopted as the shape of the pressing member, and the pressing member is not limited to the plate shape, and may be a block shape or the like. When a pressing member having a shape that can be inserted into the packing hole is employed, it is not necessary to provide a separate pressing member insertion hole in addition to the packing hole, and both the packing and the pressing member may be housed in the packing hole.

As shown in FIGS. 6 and 7, the cable gripping part 27 is a plate having a split structure with a demon part 32. A pair of cable gripping parts 27 arranged on both sides of a protrusion 33 protruding from the end face plate 21
When the optical cable 6 is fastened and integrated with a screw 29 penetrating through the cable 3, the optical cable 6 inserted into the cable hole 21 a and protruding toward the inner surface of the end face plate 21 is connected to the detent parts 3 of the two cable gripping parts 27.
The screw holes 34 formed in the projections 33 are shown in FIG. FIG. 1 (a),
As shown in (b), the tension member 6c exposed at the end of the optical cable 6 is fixed by a tension member fixing tool 37 installed at a distance from the cable gripping component 27 to the inside of the closure 20. . 1 (a) and 1 (b), the tension member fixing member 37 is provided around a fixing block 37a supported by a support member 36 (support rod) projecting from the end face plate 21 toward the inside of the closure 20. It is provided at a plurality of locations, and each is almost positioned on the center axis of the cable hole 21a of the end face plate 21.

The optical fiber 7 led out to the optical cable 6 terminal passes around the tension member fixing portion 37,
The extra length is bent and stored by being drawn from the tension member fixing portion 37 into one of a plurality of extra length storage trays 38 installed on the side opposite to the end face plate 21. In the extra length storage tray 38, an optical connection portion (optical connector, fusion splicing portion, etc.) of the optical fibers 7 is stored together with the extra length. The extra length of the optical fiber 7 housed so as to pass through the inside of the closure 20 is also curved and housed. The optical connection portion and the extra length correspond to optical components housed in the closure 20.
When the optical fiber 7 is output from the end of the optical cable 6 which is separately drawn into the closure 20 from the plurality of cable holes 21a of the end face plate 21, the number of optical connection portions and the excess length of the optical fibers 7 are plural as described above. Extra length storage tray 38
It is stored in the one selected from. On the other hand, when the optical fiber 7 is taken out from the curved portion 6a by inserting both sides of the curved portion (the virtual line 6a in FIG. 1A) formed in the optical cable 6 into the cable holes 21a, respectively, Is cut and connected to another optical fiber via the optical connection portion and stored in the extra length storage tray 38, but the other part of the optical fiber 7 is not cut and the extra length is stored in the extra length storage tray 38. There is also a case where processing is performed by storing in a curved state.

The extra-length storage tray 38 is thin in appearance.
An extension of the support member 36 or another support member fixed to the support member 36 (another support member 41 in FIGS. 1A and 1B).
A plurality of extra length storage trays 38 are stacked on the extra length storage tray 38 supported by the above, and adjacent extra length storage trays 38 are connected to each other by hinges 39 and engagement claws 40. All the extra length storage trays 38 are supported by a support member 41. The extra-length storage tray 38 has a shape in which a projecting wall is protruded substantially all around the outer peripheral portion of the bottom plate 38a. Each extra-length storage tray 38 faces the bottom plate 38a toward the support member 41, and Lamination is performed with the opening facing 38a facing in the opposite direction to the support material 41. The opening of each extra-length storage tray 38 is closed by the bottom plate 38a of the extra-length storage tray 38 that is stacked adjacent to the side opposite to the support member 41 and functions as a lid. In order to open the opening of the extra length storage tray 38, the engagement of the engaging claw 40 with the extra length storage tray 38 stacked adjacent to the side opposite to the support material 41 is released. The storage tray 38 is rotated via the hinge 39. At this time, together with the extra length storage tray 38 adjacent to the extra length storage tray 38 to be opened, all the extra length storage trays stacked from the extra length storage tray 38 on the side opposite to the support material 41. 38 is also integrally rotated. Only the extra-length storage tray 38 stacked farthest from the extra-length storage tray 38 directly supported by the support member 41 has its opening closed by the removable lid 38b. The support leg 38c attached to the lid 38b is pulled out of the lid 38b and engaged with, for example, the engaging portion 37b of the fixed block 37a, thereby rotating one or more of the plurality of rotating trays 38 with respect to the opened extra length storage tray 38. This is for supporting the extra length storage tray 38 and maintaining the open state of the target extra length storage tray 38 (FIG. 4).
reference).

In order to assemble the closure 20, before attaching the end face plate 21 to the opening 4 of the closure sleeve 3, assembling of the cable gripping part 27, insertion of the optical cable 6 into the cable hole 21a,
The optical cable 6 is fixed by a tension member fixing tool 37, the pressing mechanism 22, the pressing member 23 and the packing 24 are installed, the cable hole 21a is sealed by the packing 24 compressed and deformed by the pressing mechanism 22, and the optical fiber 7 drawn out from the optical cable 6 is formed. After that, the surplus length processing by the extra length storage tray 38 is performed, and then the end face plate 21 is attached to the opening 4 of the closure sleeve 3 to hermetically seal the whole to ensure waterproofness.

As shown in FIG. 5, the pressing member 23 and the packing 24 are housed in the packing hole 25 and the pressing member housing hole 35 before assembling the cable gripping component 27.
Next, as shown in FIG. 6, a pair of cable gripping parts 27 are installed such that the projections 33 on both sides of the cable hole 21a (the packing hole 25 and the pressing member storage hole 35) are sandwiched from both sides. The grip part 27 is attached to the protrusion 3
The optical cable 6 is gripped and fixed between the two cable gripping parts 27 by fixing with the screw 29 penetrating into the third screw hole 34. The cable gripping part 27 has a pressing member storage hole 35.
Are arranged so as to straddle. The cable gripping part 27 is fixed integrally with the end face plate 21 by screws 29. The optical cable 6 is, specifically, the cable gripping component 2
7 is sandwiched between the seven onion parts 32, so that displacement in each direction such as pulling out or pushing in is fixed so as not to be possible.

Next, as shown in FIG. 7, the screw 28 of the pressing mechanism 22 is turned from the side closer to the inside of the closure 20 than the cable gripping part 27, that is, the extra length storage tray 3
8, the screw 28 is screwed into the screw hole 27 a of the cable gripping component 27, and the screw 28 is rotated and screwed toward the end face plate 21 as shown in FIG. 8. This allows
As shown in FIG. 9B, a screw 28 that has taken a reaction force on the cable gripping component 27 is
Will be pressed. The packing 24 is compressed and deformed by being sandwiched between the supporting wall 26 of the end face plate 21 and the pressing member 23. Since the inner diameter of the packing hole 25 is substantially equal to the outer diameter of the packing 24 before the compression deformation, the pressed packing 24 eventually undergoes a deformation to reduce the diameter, and comes into close contact and pressure contact with the periphery of the optical cable 6. Thereby, the packing hole 25
And the cable hole 21a is sealed by the packing 24, and the waterproof property is secured. Note that, in FIG.
Although the cable gripping component 27 having only one 7a is illustrated, the invention is not limited to this, and a cable gripping component having a plurality of screw holes 27a and capable of screwing a plurality of screws 28 can also be employed.

The sealing of the cable hole 21a and the optical cable 6
When the excess length processing of the optical fiber 7 drawn out of the closure sleeve 3 is completed, the vicinity of the opening 4 of the closure sleeve 3 is moved to the end face plate 21
And fixed with a fixing tool such as a band 8. Thereby, the assembly of the closure 20 is completed.

According to this water stopping structure, the compressing deformation of the packing 24 by the pressing mechanism 22 is performed from the position inside the closure 20, so that when the closure 20 is assembled, the pressing mechanism 22 is exposed to the outside of the closure 20. There is no part to do. Therefore, the pressing mechanism 22 is protected from the wind and rain, as in the case where the pressing mechanism 22 is installed in a place where there is a possibility of being affected by flooding, such as a manhole or a handhole in which the closure 20 is installed, or when applied to an optical cable laid overhead. Even when installed in an exposed environment, it does not come into contact with water unless the inside of the closure 20 is flooded, so that it is difficult to corrode and the waterproofness of the cable hole can be stably maintained for a long time.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made. The optical fiber container to which the present invention is applied is not limited to a pot-shaped closure, and is a closure having a structure in which both ends of a cylindrical sleeve are closed with an end plate having a cable hole, an optical connection box other than the closure,
Various configurations can be adopted as long as they have a cable hole that needs to be sealed with waterproofness, such as an optical branch box.
As the configuration of the pressing mechanism, various configurations can be adopted as long as the packing is pressed against the wall around the cable hole to be compressed and deformed. In the above-described embodiment, the pressing mechanism has been exemplified in which the packing is pressed into the packing hole formed in the end face plate of the closure and is compressed and deformed so that the packing is brought into close contact with the optical cable periphery and the outer surface to seal the cable hole. However, the present invention is not limited to this, and it is also possible to adopt a configuration in which the packing is compressed and deformed in the packing hole formed in the member on the pressing mechanism side pressed toward the end face plate and pressed against the periphery of the optical cable. That is, it is only necessary to provide a structure in which the packing pressed by the pressing mechanism is compressed and deformed so that the cable hole can be sealed in either the wall around the cable hole or the member on the pressing mechanism side.

[0028]

As described above, according to the water blocking structure of the cable hole, the compression deformation of the packing for sealing the cable hole by the pressing mechanism is performed from the inside of the optical fiber housing. Further, the pressing mechanism can be housed in the optical fiber housing so that the pressing mechanism is not exposed outside the optical fiber housing. The pressing mechanism is corroded even if the optical fiber container is installed in places where there is a possibility of inundation such as manholes and handholes, or in environments exposed to the weather such as optical fiber containers applied to optical cables laid overhead. Therefore, the waterproofness of the cable hole can be maintained stably, and the life of the optical fiber container can be extended, and the maintenance and inspection cycle can be extended. In addition, since there is no need to take measures such as using an expensive material having excellent corrosion resistance for the components of the pressing mechanism, the use of an inexpensive material provides an excellent effect that the cost can be reduced.

According to the water stopping structure of the cable hole of the second aspect, the pressing mechanism includes a screw screwed to a cable gripping part for gripping and fixing the optical cable in the vicinity of the cable hole, and a rotation operation of the screw. And a pressing member that is driven by the device to press the packing toward the wall around the cable hole, and is configured using a cable gripping component. It has excellent effects such as downsizing and cost reduction.

According to the third aspect of the present invention, the operation of rotating the screw can be performed from a side substantially orthogonal to the axial direction of the optical cable gripped and fixed to the cable gripping component. Therefore, there is an excellent effect that the screw can be rotated efficiently without contacting other components in the optical fiber housing, the optical fiber, or the like.

[Brief description of the drawings]

FIG. 1 is a view showing a closure to which a water blocking structure for a cable hole according to the present invention is applied, wherein (a) is a plan view,
(B) is a front view.

FIG. 2 is a perspective view showing an example of a packing applied to a waterproof structure of a cable hole of the closure of FIG. 1;

FIG. 3 is a perspective view showing an example of a screw constituting a pressing mechanism of a water blocking structure of a cable hole of the closure of FIG. 1;

FIG. 4 is a side view showing a state in which an extra-length storage tray stored in the closure of FIG. 1 is opened.

FIG. 5 is a perspective view showing a method of assembling the water blocking structure of the cable hole according to the present invention, showing a step of housing the packing and the pressing member in the packing hole.

FIG. 6 is a perspective view showing a method of assembling the water blocking structure for a cable hole according to the present invention, showing a step of arranging a cable gripping component near a packing hole.

FIG. 7 is a perspective view showing a method of assembling the water blocking structure of the cable hole according to the present invention, and showing a process of fastening the cable gripping parts arranged near the packing hole to each other and fixing them to the end face plate. is there.

FIG. 8 is a view showing a method of assembling the water blocking structure of the cable hole according to the present invention, showing a step of compressing and deforming the packing in the packing hole by screwing a screw screwed into the cable gripping component. It is a perspective view.

9A and 9B are diagrams showing a water blocking structure of the cable hole according to the present invention, wherein FIG. 9A shows a state before the packing is compressed and deformed, and FIG. 9B shows a state when the packing is compressed and deformed.

FIG. 10 shows a pot-shaped closure,
(A) is a front view, (b) is an arrow view of (a), and shows an end face plate.

FIG. 11 is a cross-sectional view showing a water stop structure of a conventional example,
Shows before packing is pressed.

FIG. 12 is a cross-sectional view showing a state where the packing is pressed and deformed in the water stopping structure of FIG. 11;

[Explanation of symbols]

6 optical cable, 7 optical fiber, 20 optical fiber housing (closure), 21 wall (end face plate), 21a
Cable hole, 22: pressing mechanism, 23: pressing member (sealing washer), 24: packing, 24a: packing (packing main body), 27: cable gripping part, 28: screw.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kunihiko Jimbo, Inventor 1440, Mukurosaki, Sakura City, Chiba Prefecture Inside Fujikura Sakura Office (72) Inventor Yoshikazu Nomura 1440, Musaki, Sakura City, Chiba Prefecture F Inside Fujikura Sakura Office, Inc. Terms (Reference) 2H001 DD35 FF06 HH01 2H038 CA37 CA38 CA52 CA62

Claims (3)

[Claims] 1. A water blocking structure for a cable hole in an optical fiber housing (20) for housing an optical connection portion between optical fibers (7) drawn out from an optical cable (6) and an optical component such as an extra length. A compressible packing (24, 24a) disposed around an optical cable inserted into a cable hole (21a) penetrating the wall portion (21) of the optical fiber container; A water blocking structure for a cable hole, comprising: a pressing mechanism (22) for pressing the wall around the cable hole from inside to compress and deform the wall to seal the cable hole. 2. The cable holding component (2) for holding and fixing the optical cable in the vicinity of the cable hole.
7) a screw (28) screwed into the cable, and a pressing member (23) driven by a rotation operation of the screw to press the packing toward a wall around the cable hole. The water blocking structure for a cable hole according to claim 1, wherein 3. The cable hole according to claim 2, wherein the screw can be rotated from a side substantially orthogonal to an axial direction of the optical cable gripped and fixed to the cable gripping component. Waterproof structure.