JP2934091B2 - Hanging connection box for optical cables wound around overhead transmission lines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension type connection box for accommodating a connection portion of an optical cable wrapped around an overhead transmission line.

[0002]

2. Description of the Related Art As a method of laying an optical cable for optical communication along an overhead transmission line, a method of storing an optical cable inside an overhead ground wire and a method of wrapping and laying an optical cable around the outer circumference of an overhead ground wire are conventionally known. Is common. In each case, an overhead ground wire at the ground potential is used, so when connecting an optical cable on the way, fix the connection box directly to the steel tower and store the connection part of the optical cable in it. I have.

[0003]

On the other hand, recently, it has been studied to lay an optical cable around an overhead transmission line instead of an overhead ground line in a DC overhead transmission line or the like. When wrapping and laying an optical cable around an overhead transmission line where voltage is applied, fixing the connection box of the optical cable directly to the tower is
Transmission voltage is applied to the optical cable from the overhead transmission line to the junction box, which is dangerous.

In order to prevent a voltage from being applied to the optical cable, it is conceivable to fix a rod-shaped insulator to a steel tower and install an optical cable connection box at the end of the rod-shaped insulator.
This method has a disadvantage that the supporting structure of the optical cable connection box becomes large and the cost is increased.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a suspension type connection box suitable for storing a connection portion of an optical cable wound and laid on an overhead power transmission line. In this configuration, an attachment portion to the suspension support is integrated with an upper portion of the optical cable extra length storage portion having an annular concave groove for storing the end portion of the optical cable wrapped around the overhead power transmission line in a loop shape. And an optical cable connection part storage box detachably mounted with the optical cable introduction part positioned on the annular concave groove on the front surface of the extra cable length storage part of the case main body. It is assumed that.

[0006]

The connection box can be easily suspended and supported by attaching the mounting portion provided at the upper portion of the extra length storage portion of the optical cable to the lower portion of the suspension clamp or the like of the overhead transmission line. As a result, the connection box has the same potential as the overhead transmission line, and no voltage is applied to the optical cable.

When connecting an optical cable wrapped around an overhead power transmission line, the optical cable connection portion storage box is removed from the case body, the end of the optical cable is pulled in, and the extra length is used as the extra length storage portion. And store it in a loop. After that, the connection portion storage box is attached to the case body, the end of the optical cable is drawn into the case body, the coating is stripped off in the same manner as a normal optical cable, and the optical fiber is connected.

The connection portion storage box is made detachable and attached to the front of the extra length storage portion of the case main body.
This is because the whole is downsized to reduce the wind pressure load.
The reason why the optical cable introduction portion of the connection portion storage box is positioned on the annular groove of the extra length storage portion is that the end portion of the optical cable can be easily introduced into the detachable connection portion storage box. .

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIGS. 1 to 6 show an embodiment of a suspension type connection box according to the present invention, and FIGS. 7 and 8 show a use state thereof. FIG. 1 shows a connection box 11 of the present embodiment suspended from a clamp.
FIG. 2 is a front view showing a state in which the connection box 11 is suspended and supported, FIG. 2 is a partially cutaway front view showing the internal structure of the connection box 11, FIG. 3 is a side view of the connection box 11, and FIG. FIG. 5 is a sectional view taken along line AA of FIG. 4, and FIG. 6 is a side view taken along line BB of FIG.

The connection box 11 comprises a case body 15 as shown in FIGS. 4 to 6, and an optical cable connection portion storage box 17 mounted on the front surface thereof as shown in FIGS.

The case main body 15 has an optical cable extra length storage portion 21 having an annular concave groove 19 for accommodating an end portion of the optical cable in a loop shape, and optical cable protection tube fixing members located on both upper sides of the optical cable extra length storage portion 21. A part 23 and a mounting part 25 for attaching to a suspension support located above the optical cable extra length storage part 21 are integrally provided. The optical cable connection section storage box 17 is detachably attached to the front surface of the extra length storage section 21, and is removed from the connection section storage box 17 when the optical cable 27 is stored in the extra length storage section 21.

The optical cable 27 is connected to a protective tube 29 as shown in FIG.
Through the case body 15. The protective tube 29 has a gourd-shaped cross section, has a hole for passing the optical cable 27 on one side, and has a tensile strength member 31 embedded on the other side. The end of the protection tube 29 is fastened and fixed to the protection tube fixing portion 23 of the case body 15 by a clamp piece 33, and the end of the strength member 31 is further fixed to the case body 15 by a fastening piece 35.

The optical cable 27 drawn into the case body 15
The extra length part is rounded into a loop shape and the annular concave groove of extra length storage part 21
Stored in 19. Thereafter, the connection portion storage box 17 is attached to the front surface of the extra-length storage portion 21 by the bolt 37. The optical cable introduction section 39 of the connection section storage box 17 is located on the annular groove 19 in a state where the connection section storage box 17 is attached to the extra length storage section 21. Therefore, the end of the optical cable 27 in the annular groove 19 can be easily pulled into the connection portion storage box 17. In FIG. 2, the optical cable introduction section 39 can be seen only in the lower left portion of the connection section storage box 17, but the optical cable introduction section is similarly provided in the lower right section. The structure of the connection portion storage box 17 is substantially symmetric.

The optical cable 27 drawn into the connection portion storage box 17 is stripped of the coating, separated into an optical fiber 41 and a tension member 43, and connected to the optical fiber 41, and the tension member 43 is fixed by a grip metal 45. I do.

The connection storage box 17 is a box body.
After the connection work of the optical cable 27 is completed inside, the cover 49 is covered, and the cover 49 is fixed to the box body 47 with the bolt nut 51. Thereby, the inside of the connection portion storage box 17 is kept airtight and watertight.

Thereafter, in order to protect the extra length of the optical cable 27, an upper cover 53 is attached to the upper part of the case body 15 by bolts 55.
, And a semicircular lower cover 57 is fixed to the lower half of the extra length storage section 21 with bolts 59.

The above is the structure of the connection box 11 and how to assemble it.
This connection box 11 is normally used by being suspended below a suspension clamp 13 by a connection fitting 61 as shown in FIG. 7 and 8 show the state of use. FIG. 7 shows the case where the connection box 11 is supported by the tension portion of the overhead transmission line, and FIG. 8 shows the case where the connection box 11 is supported by the suspension portion.

7 and 8, reference numeral 63 denotes an overhead power transmission line, 65 denotes an anchoring clamp, 67 denotes a tension insulator series, 69 denotes a jumper wire, 71 denotes a suspension insulator series, 13 denotes a suspension clamp, and 27 denotes an overhead transmission line. Optical cable wrapped in a spiral around 63,
29 is an optical cable protection tube, 73 is a fixture for the optical cable protection tube 29, and 11 is a connection box.

[0019]

As described above, the connection box according to the present invention can be easily suspended and supported on the tension portion or the suspension portion of the overhead transmission line, and the connection portion of the optical cable can be safely and reliably provided. Can be protected. In addition, since it is extremely compact, the wind pressure resistance is small, and since it is a suspended support system, it is not necessary to make the support structure so large and the cost is low.

[Brief description of the drawings]

FIG. 1 is a front view showing a connection box according to one embodiment of the present invention attached to a suspension clamp.

FIG. 2 is a partially cutaway front view of the connection box of FIG. 1;

FIG. 3 is a side view of the connection box shown in FIG. 1;

FIG. 4 is a front view of a case main body constituting the connection box of FIG. 1;

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is a side view taken along the line BB in FIG. 4;

FIG. 7 is a front view showing a state where the connection box of FIG. 1 is attached to a tension portion of the overhead transmission line.

FIG. 8 is a front view showing a state where the connection box of FIG. 1 is attached to a suspension portion of an overhead transmission line.

[Explanation of symbols]

11: Suspension type connection box 13: Suspension clamp 15: Case body 17: Optical cable connection part storage box 19: Annular groove 21: Optical cable extra length storage part 23: Protection tube fixing part 25: Mounting part to suspension support 27: Optical cable 29: Optical cable protection tube 31: Tensile member 33: Clamp piece 35: Tightening piece 39: Optical cable introduction part 41: Optical fiber 43: Tension member 47: Box body 49: Lid body 53: Upper cover 57: Lower cover 63: Imaginary power line

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tadashi Ujino 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (56) References JP-A-61-83504 (JP, A) JP-A-Hei 2-125203 (JP, A) JP-A 1-71704 (JP, U) JP-A 61-38602 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02B 6/46 G02B 6/24

Claims (1)

(57) [Claims] 1. An optical cable extra length storage portion having an annular concave groove for looping and storing an end portion of an optical cable wound and laid on an overhead power transmission line, and an attachment portion to a suspension support is integrally provided. And an optical cable connection portion storage box detachably mounted on the front surface of the extra cable length storage portion of the case body with the optical cable introduction portion positioned on the annular groove. Hanging connection box for optical cables wound around overhead transmission lines.