JP3844293B2 - Optical cable grounding unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical cable grounding unit used for grounding a metal tension member of an optical cable in the middle in the longitudinal direction of the optical cable.
[0002]
[Prior art]
In an optical communication network, an optical cable with a small number of optical fibers wired to a subscriber's house is generally provided with tension members made of steel wires or the like on both sides of the optical fiber core, and a jacket is collectively applied to these members. It has a structure. When an optical cable having such a metal tension member is wired, it is necessary to ground the induced current from lightning, power lines, etc. to the ground.
[0003]
Conventionally, when grounding a tension member of an optical cable, it is common to introduce the end of the optical cable into a junction box or the like, peel off the jacket to expose the tension member, and ground at the place where the tension member is held. It was.
[0004]
[Problems to be solved by the invention]
However, when the cable connection box is grounded, there is a problem that the optical cable introduction part of the cable connection box becomes complicated. Further, since there is a case where the cable connection box does not need to be grounded, in that case, the grounding structure becomes an excessive structure and the cost is increased.
[0005]
In view of the above problems, an object of the present invention is to provide an optical cable grounding unit capable of easily grounding a tension member in the middle in the longitudinal direction instead of the end of the optical cable.
[0006]
[Means for Solving the Problems]
The optical cable grounding unit according to the present invention is used for grounding the tension member in the middle in the longitudinal direction of the optical cable in which the optical fiber core wire and the metal tension members arranged on both sides thereof are embedded in the jacket. An optical cable grounding unit,
It consists of a grounding bracket and a cable holding member
The ground metal fitting includes a first upright plate having a first edge portion that contacts one tension member exposed in the middle of the longitudinal direction of the optical cable, and a second edge portion that contacts the other tension member. A second upright plate provided with,
The cable holding member includes a first cable holding portion that holds an optical cable outside the first upright plate by applying an external force in a direction in which the one tension member is pressed against the first edge portion, and the second cable holding portion. A second cable holding portion that holds the optical cable on the outside of the upright plate by applying an external force in a direction in which the other tension member is pressed against the second edge portion.
It is characterized by this.
[0007]
In the optical cable grounding unit of the present invention, the first edge portion of the ground metal fitting is constituted by the upper end edge of the first upright plate, and the second edge portion is a hook portion formed on the upper end side of the second upright plate. It is preferable that it is comprised inside.
[0008]
In the optical cable grounding unit of the present invention, it is preferable that the distance between the first edge portion and the second edge portion of the grounding metal be set smaller than the distance between the outer surfaces of the two tension members of the optical cable.
[0009]
Further, in the optical cable grounding unit of the present invention, the cable holding member has a first side wall outside the first upright plate of the ground metal fitting, and a second side wall outside the second upright plate,
A slot in which the optical cable is inserted into the first side wall with the alignment surface of the tension member and the optical fiber core line oriented in the depth direction, and the one tension member is connected to the first edge in the optical cable inserted in the slot. A first cable holding portion configured with a pressing piece that applies an external force in a direction to be pressed against the portion is formed,
A slot in which the optical cable is inserted into the second side wall with the alignment surface of the tension member and the optical fiber core line oriented in the depth direction, and the other tension member is connected to the second edge in the optical cable inserted in the slot. A second cable holding portion configured with a bottom surface of the slot for applying an external force in a direction to be pressed against the portion is formed,
It is preferable.
[0010]
Further, in the optical cable grounding unit of the present invention, the hook portion formed on the second upright plate of the grounding bracket, and the first and second cable holding portions formed on the cable holding member include the tension member and the optical cable. It is preferable that the position is shifted in a direction intersecting with the optical cable so as to give a deflection in a direction in which the arrayed surfaces of the optical fiber cores are curved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 6 show an embodiment of an optical cable grounding unit according to the present invention, and FIG. 7 shows an example of an optical cable grounded by this grounding unit. Reference numeral 10 denotes an optical cable, and 18 denotes an optical cable grounding unit.
[0012]
As shown in FIG. 7B, the optical cable 10 has a structure in which an optical fiber core wire 12 and two metal tension members 14A and 14B arranged on both sides thereof are embedded in a jacket 16. Yes. The cross-sectional shape is a flat shape in which the width W is larger than the thickness T. In order to establish grounding in the middle in the longitudinal direction of such an optical cable 10, as shown in FIGS. 7A and 7C, the outer portions of the tension members 14A and 14B of the jacket 16 are removed as necessary sections, The tension members 14A and 14B are partially exposed.
[0013]
As shown in FIGS. 1 and 2, the optical cable grounding unit 18 includes a grounding metal 20 and a cable holding member 22. The ground metal fitting 20 is a pressed product of a metal plate, and the cable holding member 22 is a plastic molded product.
[0014]
As shown in FIGS. 1 and 3, the grounding metal 20 is one in which standing plates 26 </ b> A and 26 </ b> B are integrally provided on both sides of an elongated base plate 24, and a terminal 28 is integrally provided on one end of the base plate 24. A locking hole 30 for attaching the grounding metal fitting 20 to the cable holding member 22 is formed in the base plate 24, and a screwing hole 32 for connecting the grounding wire is formed in the terminal 28. The first upright plate 26 </ b> A has a first edge portion 34 </ b> A whose upper edge contacts with one tension member 14 </ b> A of the optical cable 10. The second upright plate 26B is higher than the first upright plate 26A, and hook portions 36 are formed at a predetermined pitch on the upper end side thereof as shown in FIG. As shown in FIG. 5E, the hook portion 36 accommodates the exposed portions of the tension members 14A and 14B of the optical cable 10 as indicated by arrows. In the case of the second upright plate 26B, the inner side of the hook portion 36 is a second edge portion 34B that contacts the other tension member 14B of the optical cable 10.
[0015]
The distance P (see FIG. 1A) between the first edge portion 34A and the second edge portion 34B is larger than the distance Q between the outer surfaces of the tension members 14A and 14B of the optical cable 10 (see FIG. 7C). It is set small.
[0016]
As shown in FIGS. 1, 2, and 4, the cable holding member 22 has a box shape, and a locking projection 40 is formed on the bottom plate portion 38 thereof. The grounding fitting 20 is attached to the cable holding member 22 by pushing the locking projection 40 into the locking hole 30 of the grounding fitting 20 as shown in FIG. As shown in FIG. 4A, a terminal block 42 in which a nut 44 is embedded is formed on one end side of the bottom plate portion 38. When the grounding metal fitting 20 is attached to the cable holding member 22, the terminal 28 rests on the terminal block 42 and is tightened with a screw 44 as shown in FIG. A ground wire (not shown) is connected to the terminal 28 by tightening a screw 44.
[0017]
Side walls 46A and 46B are integrally provided on both sides of the bottom plate portion 38 of the cable holding member 22. The first side wall 46A is located in parallel to the outside of the first upright plate 26A of the grounding metal 20, and the first side wall 46B is located in parallel to the outside of the second upright plate 26B. Slots 48A and 48B into which the optical cable 10 is inserted from the upper edge are formed at predetermined pitches on the first and second side walls 46A and 46B, respectively. The width of each slot 48A, 48B is set to be slightly larger than the thickness T of the optical cable 10 and narrower than the width W. As a result, the optical cable 10 is inserted into the slots 48A and 48B with the alignment surfaces of the tension members 14A and 14B and the optical fiber core wire 12 oriented in the depth direction of the slot, and the optical cable 10 faces in the slots 48A and 48B. Is constrained (cannot rotate).
[0018]
As shown in FIGS. 1 and 5, holding pieces 50 for holding the optical cable 10 in the slot 48 </ b> A are alternately formed at the entrance of the first slot 48 </ b> A. The presser piece 50 is formed so as to apply an external force in the direction of arrow D (the direction of pressing down) to the optical cable 10 in the slot 48A. Thus, the presser piece 50 functions to press one tension member 14A of the optical cable 10 against the first edge portion 34A. That is, the first slot 48A and the presser piece 50 constitute a first cable holding portion 52 that holds the optical cable 10 in a fixed position at a fixed position.
[0019]
On the other hand, as shown in FIGS. 1 and 6, the second slot 48B is formed shallower than the first slot 48A, and the bottom surface 54 of the second slot 48B is directed to the optical cable 10 in the slot 48B in the direction indicated by the arrow U (the direction of pushing up). It is formed at a position where an external force is applied. As a result, the bottom surface 54 of the second slot 48B functions to press the other tension member 14B of the optical cable 10 against the inside of the hook portion 36, that is, the second edge portion 34B. That is, the second slot 48B and its bottom surface 54 constitute a second cable holding portion 52B that holds the optical cable 10 at a fixed position and in a fixed posture. It should be noted that although the optical cable 10 is prevented from slipping out at the entrance of the second slot 48B, the slipping out preventing pieces 56 do not restrain the position of the optical cable 10.
[0020]
The optical cable 10 is assembled to the optical cable grounding unit 18 configured as described above as follows. First, both sides of the tension member exposed section of the optical cable 10 are inserted into the first slot 48A and the second slot 48B, and a part of the tension member exposed section is inserted inside the hook portion 36 as shown in FIG. . Further, the optical cable 10 is pushed in until it enters the lower side of the pressing piece 50 on the first slot 48A side. Then, as shown in FIG. 1A, the optical cable 10 is pushed down by the holding piece 50, pushed up by the first edge portion 34A, pushed down by the second edge portion 34B, and pushed up by the slot bottom surface 54. It will be in a wavy state. As a result, the two tension members 14A and 14B are pressed against the first and second edge portions 34A and 34B of the grounding metal 20, and a good grounding state can be obtained.
[0021]
By the way, in this optical cable grounding unit 18, the hook portion 36 of the grounding fixture 20 through which the same optical cable 10 passes and the first and second slots 48 </ b> A and 48 </ b> B of the cable holding member 22 are orthogonal to the optical cable 10 ( It is formed by shifting the position in the longitudinal direction of the grounding metal 20). In this case, the optical cable 10 passing through the grounding unit 18 is given a deflection in the direction in which the alignment surfaces of the tension members 14A and 14B and the optical fiber core wire 12 are curved (see FIG. 1B). There is no possibility that the optical cable 10 will fall on the grounding metal member 20, the contact between the tension members 14A, 14B and the edge portions 34A, 34B can be kept in a good state, and the grounding state can be kept more stably.
[0022]
【The invention's effect】
As described above, by using the optical cable grounding unit of the present invention, the tension member can be easily grounded in the middle in the longitudinal direction of the optical cable.
[Brief description of the drawings]
1A and 1B show an embodiment of an optical cable grounding unit according to the present invention, in which FIG. 1A is a cross-sectional view, and FIG.
2 is a plan view, FIG. 2 (B) is a front view, and FIG. 2 (C) is a side view.
3 shows a grounding metal fitting of the grounding unit of FIG. 2, (A) is a plan view, (B) is a front view, (C) is one side view, (D) is the other side view, (E) FIG.
4 shows a cable holding member of the grounding unit of FIG. 2, in which (A) is a longitudinal sectional view, and (B) is an enlarged view of a portion B of (A).
5 shows a first cable holding portion of the grounding unit of FIG. 2, (A) is a plan view, (B) is a sectional view taken along line BB of (A), (C) is an external view, (D ) Is an internal view.
6 shows a second cable holding part of the grounding unit of FIG. 2, (A) is a plan view, (B) is a sectional view taken along line BB of (A), (C) is an external view, (D ) Is an internal view.
7A and 7B show an example of an optical cable to be grounded, in which FIG. 7A is a front view, FIG. 7B is a cross-sectional view taken along the line BB of FIG.
[Explanation of symbols]
10: Optical cable
12: Optical fiber core
14A, 14B: Tension members
16: Jacket
18: Optical fiber grounding unit
20: Grounding bracket
22: Cable holding member
26A, 26B: Standing plate
28: Ground terminal
34A, 34B: Edge part
36: Hook part
46A, 46B: Side wall
48A, 48B: Slot
50: Presser piece
52A, 52B: Cable holder
54: Bottom of slot

Claims (5)

In the middle of the longitudinal direction of the optical cable (10) in which the optical fiber core wire (12) and the metal tension members (14A, 14B) arranged on both sides thereof are embedded in the jacket (16), 14A, 14B) an optical cable grounding unit used for grounding,
It consists of a grounding bracket (20) and a cable holding member (22).
The grounding bracket (20) includes a first upright plate (26A) having a first edge portion (34A) that contacts one tension member (14A) exposed in the middle in the longitudinal direction of the optical cable (10). And a second upright plate (26B) having a second edge portion (34B) in contact with the other tension member (14B),
The cable holding member (22) applies an external force in a direction to press the optical cable (10) outside the first upright plate (26A) and the one tension member (14A) against the first edge portion (34A). In addition, the first cable holding portion (52A) to hold, the optical cable (10) outside the second upright plate (26B), and the other tension member (14B) to the second edge portion (34B) A second cable holding part (52B) that holds and applies an external force in the direction of pressing to
An optical cable grounding unit. 2. The optical cable grounding unit according to claim 1, wherein the first edge portion (34 </ b> A) of the ground metal fitting (20) is configured by an upper end edge of the first upright plate (26), and the second edge portion (34 </ b> B). ) Is an optical cable grounding unit that is configured inside a hook portion (36) formed on the upper end side of the second upright plate (26B). The optical cable grounding unit according to claim 1 or 2, wherein a distance (P) between the first edge portion (34A) and the second edge portion (34B) of the grounding metal fitting (20) is equal to that of the optical cable (10). An optical cable grounding unit characterized by being set smaller than the distance (Q) between the outer surfaces of the two tension members (14A, 14B). The optical cable grounding unit according to any one of claims 1 to 3, wherein the cable holding member (22) has a first side wall (46A) on the outside of the first upright plate (26A) of the grounding metal fitting (20). ) Having a second side wall (46B) outside the second upright plate (26B),
A slot (48A) into which the optical cable (10) is inserted into the first side wall (46B) with the tension member (14A, 14B) and the optical fiber core wire (12) arranged in the depth direction, and this slot A first cable holding portion comprising a pressing piece (50) for applying an external force to the optical cable (10) inserted into the optical cable (10) in a direction to press the one tension member (14A) against the first edge portion (34A) (52A) is formed,
A slot (48B) into which the optical cable (10) is inserted into the second side wall (46B) with the tension member (14A, 14B) and the optical fiber core wire (12) arranged in the depth direction, and this slot A second cable holding portion comprising an optical cable (10) inserted into the slot and a slot bottom surface (54) for applying an external force in a direction in which the other tension member (14B) is pressed against the second edge portion (34B). (52B) is formed,
An optical cable grounding unit. The optical cable grounding unit according to any one of claims 2 to 4, wherein the hook part (36 and the cable holding member (22) formed on the second upright plate (26B) of the grounding bracket (20) are formed. The first and second cable holding portions (52A, 52B) that have been made give the optical cable (10) deflection in a direction in which the alignment surfaces of the tension members (14A, 14B) and the optical fiber core wire (12) are curved. As described above, the optical cable grounding unit is formed by shifting the position in the direction intersecting the optical cable (10).

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