JP3333262B2 - Bending-resistant optical cable and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending-resistant optical cable and a method for manufacturing the same.

[0002]

2. Description of the Related Art In Japan, a so-called spacer type optical cable is mainly used for communication. It bored a circular cross section several not in the outer periphery of the spacer to 10 several spiral (helix) shaped grooves, summarizes several of fiber optic lines <br/> therein into a tape In this case, a plurality of tape cores are fitted in a laminated shape.

[0003] optical cable of this type impairs the transfer characteristic of the optical fiber I written excessive tensile stress in the ribbon 1 when bending it as shown in FIG. 5, the extreme case this is cut There is a drawback that it becomes a big accident.

[0004] The reason for originally forming the grooves 3 of the spacer 2 in a spiral shape is located inside and outside in the radial direction from the tension member 9 is groove 3 becomes a neutral plane of bending as demonstrated in Fig. 5 Therefore, during bending, a tensile stress is applied to the optical fiber 1 near the groove portion 3A located outside the neutral surface, but the optical fiber 1 near the groove portion 3B located inside the neutral surface is reversed. Is applied, and as a result , the tensile and compressive stresses applied to the optical fiber 1 are offset as a whole.

[0005]

However, if the bending of the spacer 2 occurs within a range shorter than the length of the half pitch (p / 2) of the spiral of the groove 3, the above-described principle of cancellation does not work sufficiently. Then, a situation occurs in which the characteristics of the optical fiber included in the tape core 1 are impaired. Especially recently communication line is congested as, or in a situation where when the communication device is Ru Tei forced optical cable laying set or Installing involves bending by a small radius of curvature and miniaturization has increased, the problem The solution is urgent.

[0006]

SUMMARY OF THE INVENTION The present invention was made to solve the problems described above, according to claim 1
Solution Kette stage of its the helix of the plurality of outer peripheral portions of the spacer
Each stack-like ribbon is dropped into linear monographs groove
Optical cable that is inserted and wrapped from the outside
In the material where the tape core wire is easily broken or stretched at appropriate intervals in the longitudinal direction of the spacer.
The bottom of each groove by the interposition of a winding ring
That the raised part is formed
And a flexure-resistant optical cable.

[0007] As a solution according to the invention of claim 2 has on its outer peripheral portion of <br/> spacer helixes shaped grooves of the plurality of are formed in the outer peripheral portion, suitable intervals in the longitudinal direction with, fracture, or a step of winding the winding ring of elongated material easily, darken the ribbon on the spacer, the winding position of the winding ring Sheng said ribbon from protruding outside the groove a step of providing a vanishing part Ri, the tape is subjected to winding pressing the outer periphery of said spacer
Pressing the core wire radially inward, and thereby
Floating on the groove bottom is pushed breaking the winding ring, or to extend the Sheng Riue <br/> rising section to the strip groove Te
Forming a flexure-resistant optical cable.

[0008]

1 is a side sectional view showing a spacer type optical cable according to the first aspect of the present invention. For simplicity, only one groove 3 is drawn on the spacer 2 and the tension member is omitted.
Oh Ru, but grooves 3 actually is what is conformally plurality of bored in the outer periphery of the spacer 2. The tape core wire 1 fitted into the groove 3 has a raised portion 1A as shown in the figure.
Therefore, the tape core wire 1 is longer than the actual length of the groove 3 in this portion, so that the tape core wire 1 is not subjected to an excessive tensile stress upon bending.

[0009] ribbon 1 as shown in FIG. 1 is groove 3
How we actually manufactured an optical cable having a floating portion 1A at the inner is performed by steps shown in FIGS.

[0010] That is, first, as shown in FIG. 2, wound around the winding ring 4 with a pre-applied <br/> Yichun intervals in the longitudinal direction of the spacer 2 to fit the ribbon 1. The winding ring 4 is made of a material that is easily broken or stretched, such as a thin narrow paper tape or rubber band, and has a size that is at least larger than the pitch p of the helix line of the groove .

[0011] As the normal to the scan pacer 2 as shown in the following Figure 3 dropped the ribbon 1. Then winding ring 4
The position from ribbon 1 extends the upper side of the winding ring 4, wherein the Sheng Ri vanishing part 1B of the ribbon 1 is formed.

After that, when the ordinary press winding 5 is applied, FIG.
The Sheng Ri vanishing part 1B of the ribbon 1, as shown by being pressed by the pressing winding 5 sink radially inward, fits inside the groove 3. In this case, the winding ring 4 or is disconnected, or is either extending only the necessary length, the winding ring 4 at this time in any event is not already finished serve, also wound ring described above There is no problem if a small amount of material such as thin paper 4 remains under the tape core 1 .

[0013]

According to the present invention, there is provided a spacer type optical cable.
The tape core dropped into the spacer in the longitudinal direction.
Has raised parts from the bottom of the groove at appropriate intervals
In order, I longer than the actual length along the helix of the groove
Ri, thus there is an advantage that not subjected to excessive tensile stress during flexing of the spacer.

According to a second aspect of the present invention, there is provided the manufacturing method of
Just insert the winding ring at an appropriate interval in the hand direction
Method, the current amount of tape core drop
Easy to add winding ring feeder to industrial machinery
No need to reduce production efficiency
And has the advantage of being a highly effective method.

[Brief description of the drawings]

FIG. 1 is a side sectional view along one groove showing one embodiment of the present invention.

FIG. 2 is a side view showing a state in which a winding ring is wound around an outer periphery of a spacer.

FIG. 3 is a side sectional view along one groove showing a state where a tape core is dropped from above a winding ring.

4 is a side sectional view of a presser winding the shaped <br/> state on the spacer in the state of FIG.

FIG. 5 is a side sectional view illustrating bending of the spacer type optical cable.

[Explanation of symbols]

 1 tape core 1ARiseDepartment1B swell  2 Spacer 3Groove  4 winding ring 5 holding roll

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-94211 (JP, A) JP-A-61-73914 (JP, A) JP-A-61-284712 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) G02B 6/00 G02B 6/44

Claims (2)

(57) [Claims] 1. A plurality of temples on an outer peripheral portion of a spacer (2).
A laminated tape core (1) is dropped into each of the wire-shaped grooves (3), and a holding roll (5) is formed from the outside.
An optical cable comprising:
(1) The spacers (2) at appropriate intervals in the longitudinal direction.
, A wound ring of material that is easily broken or stretched
(4) is interposed so that the bottom of each groove (3)
(1A) is formed, which is raised from
A bending-resistant optical cable, comprising: 2. A plurality of helix linear grooves on an outer peripheral portion.
On the outer peripheral portion of the spacer (3) is drilled (2), a step of having an appropriate spacing in the longitudinal direction and wound breaking or winding ring of elongated material that easily (4),
Drop the ribbon (1) into the spacer (2),
A step of providing said ribbon (1) is Sheng Ri vanishing part protruding outside the groove (3) (1B) in the winding position of the winding ring (4), pressing on the outer circumference of the spacer (2) Winding (5) and radiusing the tape core wire (1)
A step of pressing the inward, whereby the write Nde groove bottom press the take-ring (4) the Sheng Ri vanishing part breaks, or is extended by the the (1B) in the groove (3) in
Forming as a raised portion (1A) of the optical fiber cable .