JP5123695B2 - Optical fiber drop box and its mounting method - Google Patents

Description

  The present invention relates to an optical fiber dropping box for drawing an optical fiber into a house and a mounting method thereof.

The optical cable protruding from the station is pulled up at a certain point and is pulled into the house through a plurality of closures provided at the poles. As a closure for drawing an optical cable into a house, for example, the one described in Patent Document 1 below is known.
JP 2008-26388 A

  However, since the closure described in Patent Document 1 is large, it is installed at the side of a utility pole, and the closure is not installed at every side of a utility pole. Therefore, when drawing the optical fiber into the house, it is necessary to pass a drop cable from the closure installation point via a plurality of utility poles. For this reason, many drop cables are required, and the time required for laying the drop cables increases.

  The present invention has been made in order to solve the above-mentioned problems, and while reducing the size of the box, an optical fiber dropping box capable of drawing an optical fiber from the vicinity of the house into the house by a simple operation and the box An object is to provide an attachment method.

  An optical fiber dropping box according to the present invention is taken out from a box main body, a guide portion for guiding the first optical cable so as to penetrate the box main body, and the first optical cable housed in the box main body and guided by the guide portion. A connecting portion that connects the first optical fiber core wire and the second optical fiber core wire of the second optical cable, and a connecting portion fixing portion that is accommodated in the box body and fixes the connecting portion at an arbitrary position in the box body. And comprising.

  According to such an optical fiber dropping box (hereinafter, also simply referred to as “dropping box”), the box body accommodates a connecting portion for connecting two optical cables and a connecting portion fixing portion for fixing the connecting portion. About the size is enough. As a result, the size of the drop-down box can be kept small, and the drop-down box can be installed at an arbitrary position between the power poles as well as the utility pole. In addition, according to this drop-down box, the connection portion can be fixed at an arbitrary position in the box body, so that the operator needs to strictly adjust the lengths of the two optical fiber core wires taken out for connection. There is no. Therefore, it is possible to reduce the size of the box and to draw the optical fiber from the vicinity of the house into the house with a simple operation.

  In the optical fiber dropping box of the present invention, it is preferable that the connection portion fixing portion fixes the connection portion at an arbitrary position along the direction in which the first optical cable guided by the guide portion extends.

  In this case, since the connection portion can be positioned along the direction in which the first optical cable extends, it is not necessary to strictly adjust the length of the first optical fiber core wire to be taken out. Therefore, the worker can draw the optical fiber into the house from the vicinity of the house with a simple work.

  In the optical fiber drawing box of the present invention, a plurality of connecting portion fixing portions are provided at predetermined intervals along the direction in which the first optical cable guided by the guide portion extends, and is a rod-like member extending in a direction orthogonal to the direction. Are provided near both ends in the direction in which the first optical cable guided by the guide portion extends, and engages with the rod-like member. It is preferable to include a connection portion accommodating portion having a U-shaped protrusion.

  In this case, since the connection portion is fixed by engaging the protrusion of the connection portion housing portion with the rod-shaped member of the base portion, the connection portion can be more easily fixed.

  In the optical fiber dropping box according to the present invention, the connection portion accommodating portion can be rotated within a predetermined angle or less with respect to the base portion in a state where one of the protrusions is engaged with the rod-shaped member. Preferably there is.

  In this case, in a state where one protrusion is engaged with the rod-shaped member, the rotation range of the connection portion accommodating portion is limited to a predetermined angle or less, so that the connected optical fiber core wire is inadvertently bent. Therefore, it is possible to easily attach and detach the optical fiber to and from the connection portion.

  In the optical fiber dropping box of the present invention, it is preferable that the end of one of the protrusions is curved in the direction of the opening of the one protrusion.

  In this case, since the end portion of the one protrusion is curved so as to narrow the opening, the rotation range of the connection portion accommodating portion can be limited when the protrusion is engaged with the rod-shaped member. Thereby, it becomes possible to easily attach and detach the optical fiber core to and from the connection portion without inadvertently bending the connected optical fiber core wire.

  In the optical fiber drawing box of the present invention, it is preferable that a plurality of holes are formed in the box body.

  In this case, the moisture that has entered the box body volatilizes through the holes, so that the deterioration of the connection portion, the optical fiber core wire, and the like housed in the box body can be more reliably prevented.

  The method for attaching the optical fiber dropping box according to the present invention includes the steps of preparing the optical fiber dropping box, the first optical cable, and the second optical cable, and a first optical fiber core having a predetermined length from the prepared first optical cable. A step of taking out the second optical fiber core wire of a predetermined length from the prepared second optical cable, and a step of connecting the taken out first optical fiber core wire and the second optical fiber core wire by the connecting portion And, after connecting the first optical fiber core wire and the second optical fiber core wire, determining the position of the connection portion in the box body and fixing the connection portion by the connection portion fixing portion, and prepared A step of guiding the first optical cable by the guide portion, and a step of accommodating the connection portion fixing portion to which the connection portion is fixed in the box body.

In such an optical fiber dropping box mounting method, the position of the connecting portion in the box body is determined after connecting the two optical fiber core wires, and the connecting portion is fixed by the connecting portion fixing portion. It is not necessary to strictly adjust the lengths of the two optical fiber core wires taken out for connection. In addition, the size of the drop-down box can be reduced because the optical fiber drop-down box to be attached is small enough to accommodate the connection portion that connects the two optical cables and the connection portion fixing portion that fixes the connection portion. Can be suppressed. Therefore, the operator can install the drop box at any position between the utility poles, not limited to the case of the utility pole. As described above, the worker can draw the optical fiber into the house from the vicinity of the house with a simple work.

  According to such an optical fiber drawing box and its mounting method, it is possible to reduce the size of the box and to draw the optical fiber from the vicinity of the house into the house with a simple operation.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

  First, the structure of the optical fiber dropping box according to the embodiment will be described with reference to FIGS. FIG. 1 is a perspective view of an optical fiber dropping box. FIG. 2 is a diagram illustrating an open state of the box body illustrated in FIG. 1. FIG. 3 is a side view of the main cable guided to the optical fiber drawing box. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a perspective view of the connecting portion fixing portion indicated by a broken line in FIG. FIG. 6 is an enlarged perspective view of a main part of the connection portion fixing portion shown in FIG. FIG. 7 is a perspective view of the connecting portion accommodating portion shown in FIG. 6 as viewed from below. FIG. 8 is a perspective view showing a state after the connection portion accommodating portion is rotated.

  An optical fiber dropping box 1 includes a main cable (first optical cable) 2 that is pulled up through a plurality of utility poles, and a drop cable (for pulling an optical fiber network constituted by the main cable 2 into a home) This is a housing for housing the connecting portion 20 for connecting the second optical cable 3.

  Before describing the optical fiber dropping box 1, the configuration of the main cable 2 will be briefly described. As shown in FIGS. 3 and 4, the main cable 2 includes a cable body portion 211, a support wire portion 212, and a plurality of connecting portions 213 that partially connect the cable body portion 211 and the support wire portion 212. It consists of The cable main body 211 is arranged on both sides of a plurality of optical fiber core wires (first optical fiber core wires) 214 (four in FIG. 4) arranged side by side and the alignment of these optical fiber core wires 214. A pair of tension members 215 and a jacket 216 that collectively covers the optical fiber core wire 214 and the tension member 215 are configured. The support line portion 212 includes a support line 217 and a jacket 218 that covers the support line 217. The connecting portion 213 is formed of the same material as the outer cover 216 and the outer cover 218.

  The configuration of the drop cable 3 is the same as that of the main cable 2, but the number of optical fiber core wires (second optical fiber core wires) may be different from that of the main cable 2, for example, one or two.

  Next, the configuration of the optical fiber dropping box 1 will be specifically described. The optical fiber drawing box 1 includes a box body 10, a connection part 20, and a connection part fixing part 30. The material of the optical fiber dropping box 1 (in particular, the material of the box body 10 and the connecting portion fixing portion 30) is plastic. The optical fiber dropping box 1 (box body 10) has an elongated shape, and its lower surface 16 is formed such that the center portion swells downward from the end portion in the longitudinal direction. As an example, the length of the optical fiber dropping box 1 is 334 mm, the height is 31 mm at the end in the longitudinal direction, and 37.6 mm at the center. Is not limited to these.

  The box body 10 includes an accommodating portion 11 having an elongated accommodating space 13 formed therein, a lid portion 12 capable of opening and closing the accommodating space 13, and guide portions formed at both longitudinal ends of the accommodating portion 11. 14 and the guide part 15 formed similarly (refer FIG. 2). A plurality of holes (not shown) are formed in the box body 10, and the diameter of the holes is about 100 μm. Although the formation location of a hole is not limited, For example, it can be provided in the upper surface (not shown) and the lower surface 16 of the box main body 10. FIG. The box body 10 has a symmetrical shape when viewed from one side surface 17 thereof. These holes are preferably fine holes having a diameter of 1 mm or less.

  The accommodating space 13 is large enough to accommodate a connecting portion 20 and a connecting portion fixing portion 30 described later. The guide part 14 is provided to guide the main cable 2 so as to penetrate the box body 10 and includes a guide part 14a and a guide part 14b. The guide portions 14 a and 14 b guide the cable main body portion 211 and the support wire portion 212 of the main cable 2, respectively, and are both formed in a cutout shape on the short side of the opening portion 18 of the housing portion 11. The guide portion 15 is provided to guide the drop cable 3 into the box body 10, and is formed in a cutout shape on the short side of the opening 18 of the housing portion 11.

  The connection unit 20 is a field-attached connector that connects the optical fiber core 214 extracted from the main cable 2 guided into the box body 10 by the guide unit 14 and the optical fiber core of the drop cable 3. This connection part 20 is accommodated in the box main body 10 in a state of being fixed to a connection part fixing part 30 described later. In addition, the member used as the connection part 20 is not limited to the on-site connector described in this embodiment, For example, a mechanical splice can be used as the connection part 20 and is not limited to the on-site connector.

  The connection portion fixing portion 30 is a member for fixing the connection portion 20 at an arbitrary position in the box body 10 and is accommodated in the box body 10. The connection part fixing | fixed part 30 is provided with the base part 31 and the connection part accommodating part 32 (refer FIG. 5).

  The base portion 31 is a member having a substantially plate shape and an elongated shape similar to that of the accommodation space 13. The base portion 31 includes a main cable fixing portion 33, a drop cable fixing portion 34, a support claw 35, and a rod-like member 36. Since each component of the base part 31 is integrally formed, it is possible to realize high strength and cost reduction during manufacturing. The base portion 31 is fixed in the accommodation space 13 by locking means (not shown). The base portion 31 has a symmetrical shape when viewed from one side surface 37 thereof.

  The main cable fixing portion 33 is provided at both ends in the longitudinal direction of the base portion 31 and has a function of fixing the cable main body portion 211 of the main cable 2 extending along that direction. That is, the direction in which the main cable 2 extends substantially coincides with the longitudinal direction of the base portion 31. The main cable fixing portion 33 includes a substantially U-shaped fixing member 33a formed so as to sandwich the cable main body portion 211, and a receiving hole (not shown) into which the fixing member can be fitted. It is configured. The support line portion 212 of the main cable 2 is fixed to the base portion 31 using means such as a fixing band.

  The drop cable fixing portion 34 is substantially U-shaped, and is provided at both ends of the base portion 31 in the longitudinal direction. The drop cable fixing unit 34 has a function of fixing the drop cable 3 connected to the connection unit 20 by gripping it.

  A plurality of support claws 35 are provided on the line connecting the two main cable fixing portions 33 (along the longitudinal direction of the base portion 31) at a predetermined interval, and the cable main body portion 211 fixed to the base portion 31 is provided. It has a function of supporting the (optical fiber core wire 214).

  A plurality of rod-shaped members 36 are provided at predetermined intervals on the line connecting the two drop cable fixing portions 34 (along the longitudinal direction of the base portion 31). Each bar-shaped member 36 extends in a direction orthogonal to the longitudinal direction of the base portion 31.

  The connection part accommodating part 32 is comprised including the accommodating part 38 which accommodates the connection part 20, and the protrusion 40 provided in the lower surface of the accommodating part 38 (refer FIG. 7). The accommodating part 38 is comprised including the substantially rectangular support stand 38a and a pair of side wall 38b connected to each long side part of this support stand 38a.

  Two protrusions 40 are provided near both ends in the longitudinal direction of the lower surface 39 of the support base 38a. Each protrusion 40 is formed in a U shape so as to be able to engage with an arbitrary rod-shaped member 36. This is because the protrusion 40 can fix the connection portion accommodating portion 32 to the base portion 31 at an arbitrary position along the longitudinal direction of the base portion 31, in other words, the connection portion 20 can be arbitrarily fixed along the longitudinal direction of the box body 10. It means that it can be fixed in position. Of the four protrusions, two protrusions (hereinafter also referred to as “protrusions 41”) provided near one end in the longitudinal direction of the lower surface 39 are two protrusions (hereinafter also referred to as “protrusion 41”). Hereinafter, it is also referred to as “protrusion 42”. Further, the end 41a of the protrusion 41 is curved in the direction of the opening 41b.

  According to such an optical fiber dropping box 1, the box body 10 is sufficient to accommodate the connection part 20 and the connection part fixing part 30. As a result, the size of the optical fiber dropping box 1 can be reduced, and the optical fiber dropping box 1 can be installed not only at the utility pole but also at any position between the utility poles. Moreover, since the connection part 20 can be positioned along the direction where the main cable 2 is extended, the operator does not need to adjust exactly the length of the two optical fiber core wires taken out for connection. Therefore, it is possible to reduce the size of the optical fiber dropping box 1 and to draw the optical fiber from the vicinity of the house into the house with a simple operation.

  Moreover, since the connection part 20 is fixed by engaging the protrusion 40 of the connection part accommodating part 32, and the rod-shaped member 36 of the base part 31, a connection part can be fixed more easily.

  Further, since the end 41a of the protrusion 41 is curved so as to narrow the opening 41b, when the protrusion 41 is engaged with the rod-shaped member 36, the rotation range of the connection portion accommodating portion 32 can be limited. For example, when the protrusion 42 is rotated away from the rod-shaped member 36, the rotation range can be limited so that the connection portion accommodating portion 32 rotates with the state shown in FIG. As an angle which the base part 31 and the lower surface 39 of the connection part accommodating part 32 make, it is possible to limit to the range of 0-30 degree | times, for example. Thereby, it becomes possible to easily attach and detach the optical fiber core to and from the connecting portion 20 without inadvertently bending the connected optical fiber core (for example, the optical fiber cable 214 of the main cable 2) (see FIG. 8).

  In addition, since the moisture that has entered the box body 10 volatilizes through the holes, it is possible to more reliably prevent deterioration of the connecting portion 20 and the optical fiber core wire that are accommodated in the box body 10.

  Further, since the optical fiber dropping box 1 is made of plastic, it is lightweight, and even if the optical fiber dropping box 1 is attached to the main cable 2 between the power poles, the load applied to the main cable 2 is small. Therefore, the optical fiber dropping box 1 can be installed at an arbitrary position between the utility poles without worrying about loosening of the main cable 2 or the like.

  Next, a method for attaching the optical fiber dropping box 1 will be described. The optical fiber dropping box 1 is attached by fixing the connecting portion 20 where the optical fiber core wire 214 of the main cable 2 and the optical fiber core wire of the drop cable 3 are connected to the connecting portion fixing portion 30. This means a series of operations for accommodating the connection fixing portion 30 in the box body 10.

  First, an optical fiber dropping box 1, a main cable 2, and a drop cable 3 are prepared. Subsequently, the cable main body portion 211 and the support wire portion 212 are separated from a part of the main cable 2, and the optical fiber core wire 214 is formed by removing the outer sheath of a predetermined length in the separated cable main body portion 211. Take out. Subsequently, one of the exposed optical fiber core wires 214 is cut halfway, and the terminal of the cut optical fiber core wire 214 is processed and then connected to the connection unit 20.

  Subsequently, the support line is separated from the tip of the drop cable 3 by a predetermined length, and the support line is fixed to a fixture (not shown), and then the outer cover of the tip of the drop cable 3 is removed to remove the light of a predetermined length. Take out the fiber core. Subsequently, the exposed end of the optical fiber core is processed and then fixed to the connecting portion 20. Thereby, the optical fiber core wire 214 of the main cable 2 and the optical fiber core wire of the drop cable 3 are connected via the connection part 20.

  Subsequently, the connecting portion 20 connecting the main cable 2 and the drop cable 3 is accommodated and fixed in the connecting portion accommodating portion 32. Subsequently, the connecting portion accommodating portion 32 is aligned with the base portion 31 according to the length of the optical fiber core wire 214 connected to the connecting portion 20, and the protrusion 40 of the connecting portion accommodating portion 32 and the rod shape of the base portion 31 are aligned. The connection part accommodating part 32 is fixed to the base part 31 by engaging the member 36 (refer FIG. 6). Here, since the shape of the base portion 31 has an elongated shape similar to that of the accommodation space 13, the alignment of the connection portion accommodation portion 32 with respect to the base portion 31 is the position of the connection portion 20 in the box body 10. Is synonymous with determining. Further, the main cable 2 is fixed to the main cable fixing portion 33 and the drop cable 3 is fixed to the drop cable 3. Thereby, the connection part accommodating part 32, the main cable 2, and the drop cable 3 are fixed to the connection part fixing | fixed part 30 (refer FIG. 5).

  Then, the connection part fixing | fixed part 30 to which the connection part 20 was fixed is accommodated in the box main body 10 (accommodation space 13). At this time, the main cable 2 and the drop cable 3 fixed to the connecting portion fixing portion 30 are pushed into the guide portions 14 and 15, respectively. Subsequently, the lid 12 is closed and the accommodation space 13 is hermetically sealed, so that the connecting portion fixing portion 30 is completely covered with the optical fiber dropping box 1 as shown in FIG. Thus, the mounting of the optical fiber dropping box 1 is completed.

  According to such an attachment method, since the position of the connecting portion 20 in the box body 10 is determined after connecting the two optical fiber core wires, and the connecting portion 20 is fixed by the connecting portion fixing portion 30, the operator can The optical fiber can be drawn into the house from the vicinity of the house by a simple operation without strictly adjusting the lengths of the two optical fiber core wires taken out for connection.

  The present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above embodiment. The present invention can be modified in various ways as described below without departing from the scope of the invention.

  In the above embodiment, the main cable 2 is shown in which the cable main body 211 and the support wire portion 212 are partially connected by the plurality of connecting portions 213, but the cable main body 211 and the support wire portion 212 are connected to each other. It may be connected continuously.

  In the above-described embodiment, the protrusion 41 is formed longer than the protrusion 42 and the protrusion 41a is curved. However, the protrusion 41 and the protrusion 42 may have the same length, or the end 41a of the protrusion 41 is curved. You don't have to. Moreover, in the said embodiment, although the hole (not shown) was formed in the box main body 10, it is not necessary to form a hole.

It is a perspective view of the box for optical fiber dropping concerning an embodiment. It is a figure which shows the open state of the box main body shown in FIG. It is a side view of the main cable guided to the optical fiber drawing box shown in FIG. It is the IV-IV sectional view taken on the line of FIG. It is a perspective view of the connection part fixing | fixed part shown with a broken line in FIG. It is the perspective view which expanded the principal part of the connection part fixing | fixed part shown in FIG. It is the perspective view which looked at the connection part accommodating part shown in FIG. 6 from the downward direction. It is a perspective view which shows the mode after the rotation of a connection part accommodating part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Optical fiber drop box, 2 ... Main cable (1st optical cable), 3 ... Drop cable (2nd optical cable), 10 ... Box main body, 14, 14a, 14b ... Guide part, 20 ... Connection part, 30 ... Connection Part fixing part, 31 ... base part, 32 ... connection part accommodating part, 36 ... rod-shaped member, 38 ... accommodating part, 39 ... lower surface of accommodating part, 40, 41, 42 ... projection, 41a ... end part of projection, 41b ... Opening of protrusion, 214... Optical fiber core wire of main cable.

Claims (5)

The box body,
A guide portion for guiding the first optical cable so as to penetrate the box body;
A connection part for connecting the first optical fiber core wire taken out from the first optical cable housed in the box body and guided by the guide part and the second optical fiber core wire of the second optical cable;
A connection portion fixing portion that is accommodated in the box body and fixes the connection portion at an arbitrary position in the box body;
Equipped with a,
The connection portion fixing portion fixes the connection portion at an arbitrary position along a direction in which the first optical cable guided by the guide portion extends,
The connecting portion fixing portion is
A base portion having a plurality of rod-like members extending in a direction perpendicular to the direction, provided in a plurality at predetermined intervals along a direction in which the first optical cable guided by the guide portion extends;
A U-shape that is provided in the vicinity of both ends in the direction in which the first optical cable guided by the guide portion extends among the accommodation portion that accommodates the connection portion and the lower surface of the accommodation portion, and engages with the rod-shaped member. A connection portion accommodating portion having a protrusion;
Comprising
Optical fiber drop box. The connection portion accommodating portion is rotatable within a range of a predetermined angle or less with respect to the base portion in a state where one of the protrusions is engaged with the rod-shaped member.
The optical fiber drawing box according to claim 1 . The end of one of the protrusions is curved in the direction of the opening of the one protrusion,
The optical fiber dropping box according to claim 1 or 2 . A plurality of holes are formed in the box body,
The box for optical fiber dropping according to any one of claims 1 to 3 . Preparing the optical fiber drop box according to claim 1, the first optical cable, and the second optical cable;
Extracting the first optical fiber core having a predetermined length from the prepared first optical cable;
A step of taking out the second optical fiber core having a predetermined length from the prepared second optical cable;
Connecting the taken-out first optical fiber core wire and the second optical fiber core wire by the connecting portion;
After connecting the first optical fiber core wire and the second optical fiber core wire, determining the position of the connection portion in the box body, and fixing the connection portion by the connection portion fixing portion;
A step of guiding the prepared first optical cable by the guide unit;
Accommodating the connection portion fixing portion to which the connection portion is fixed in the box body;
Mounting method of optical fiber drop box including

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