JPH0727957A - Optical cable manufacturing method - Google Patents

Abstract

(57) [Summary] [Objective] There is a proposal that an optical fiber 20 is housed in the spiral grooves 16 and 18 of a two-groove groove 10 to form a unit 24, and the unit 24 is assembled to form an optical cable. While this cable has many advantages, it requires high-precision spiral groove dimensions and is difficult to manufacture. It is difficult to control because the optical fibers are gathered while detecting spiral grooves, and the manufacturing equipment becomes large. was there. Solve this. [Structure] Central tension member 1 in a twisted state
2 is sent out, and the groove main body 14 having the straight grooves 16 and 18 is extruded thereon. The straight groove can be easily formed, the dimensional accuracy is high, and the optical fiber can be easily housed in the straight groove. After that, the twist of the tension member 12 is released, and the groove body 14 is twisted to deform the straight groove and the optical fiber therein in a spiral shape. This idea can be applied to a known slot type optical cable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical cable, and more particularly to a process for manufacturing a unit in a two-groove groove type optical cable described later. However, the present invention can also be applied to manufacture of a known slot type optical cable (see FIG. 5).

[0002]

2. Description of the Related Art A two-groove groove type optical cable illustrated in FIG. 3 has been proposed. [Structure] Reference numeral 10 in FIGS. 1A and 1B indicates a two-groove groove. This is a slender cylindrical body 14 having a tension member 12 in the center, and two back-to-back grooves 16, 1.
8 is provided in a spiral shape. Note that (b) is (a)
It is a B section. The optical fiber 20 is housed in the spiral grooves 16 and 18, and the holding tape 22 is wound to form the unit 24 (c). Collect this unit 24,
The optical cable 26 is used (d).

[Manufacture of 2-groove groove 10] A plastic such as polyethylene is extruded around the center tension member 12. At this time, by rotating the die, the main body 14 having the spiral grooves 16 and 18 having a predetermined pitch is obtained. [Assembly of Optical Fibers 20] Generally, as shown in FIG.
Using the delivery-winding rotary type gathering machine, while detecting the position of the spiral groove of the groove 10, the optical fiber 2 is inserted into them.
Store 0.

[0004]

[Problems to be Solved by the Invention]

(1) Usually, a large number of tape-shaped optical fibers 20 are laminated in the grooves 16 and 18. In order to maintain the arrangement of these tape fibers, the groove dimensions are required to have high precision. However, it is extremely difficult to form a highly accurate spiral groove by the above extrusion molding. Therefore, the manufacturing linear velocity does not increase, the yield also deteriorates, and the cost increases. (2) As described above, by the delivery-winding rotary type collecting machine,
In order to store the optical fiber 20 while detecting the position of the spiral groove, it is necessary to increase the size of the manufacturing apparatus and increase the accuracy of control, which leads to an increase in the cost of manufacturing equipment.

(3) These problems also apply to the slot type optical cable shown in FIG. Again, the slot 11 is made by extruding the body 17 with the spiral groove 15 over the central tension member 13.
While detecting the spiral groove 15, the optical fiber 20
Are stored to form a unit 19, and the units 19 are assembled to form an optical cable 21. Therefore, the same problem as in the two-groove groove type becomes a problem.

[0006]

As illustrated in a model in FIG. 1, (1) a central tension member 12 is continuously fed in a twisted state, and a straight (not a spiral, The groove 10 or slot body 14 having grooves 16, 18 (parallel to the groove axis) is extruded, (2) after which the twisting of the tension member 12 is released to impart a twist to the groove or slot body 14. Then, the straight grooves 16 and 18 are spirally deformed.

[0007]

[Work]

(1) When a groove or slot body having a straight groove is extruded on the center tension member 12, it is not necessary to rotate the die as in the conventional case, and the groove or slot body is easily manufactured. .
Further, the groove dimension accuracy is improved and the manufacturing speed is increased. (2) The optical fiber can be stored in the straight groove. (3) The main body of the groove or slot is extruded onto the twisted central tension member, and the twist is released later, so that the main body of the groove or slot is easily and comfortably twisted. The straight groove is spirally deformed.

[0008]

[Description of Specific Example] An example of a two-groove type optical cable will be described. [Structure] FIG. 1 schematically shows an example of manufacturing the unit 24. 30 is a delivery device for the central tension member 12, 32 is an extruder, 34 is a cooling device, 36 is a delivery device for the optical fiber 20, 38 is a collecting device, 40 is a tape winding device, 42 is a take-up device, and 44 is a device. A winding device for the unit 24.

[Manufacture of Unit 24] (1) When the central tension member 12 is continuously fed from the feeding device 30, the feeding device 30 is rotated as indicated by an arrow 31 to give a twist to the central tension member 12. . For the central tension member 12, a material such as steel wire or FRP having a large tensile strength and a large elastic limit is used. (2) On the central tension member 12 which is given a twist,
The main body 14 of the two-groove groove 10 having the straight grooves 16 and 18 is formed by the extruder 32, and the cooling device 34 is passed through the main body 14. (3) In the assembling device 38, the optical fibers 20 are assembled into the straight grooves 16 and 18 of the two-groove groove 10.

The part of the collecting device 38 is enlarged and shown in FIG. (A) is a two-groove groove 1 with the groove 16 in the front
0 is a side view of the model as seen from the side, (b) is its B sectional view, and (c) is an assembling device 38 seen from the C direction (from a direction different from 90 ° from (a)). FIG. The main body 380 of the collecting device 38 has a disc shape, is stationary (does not rotate), and the two-groove groove 10 passes through the center thereof. The claw 382 protrudes inside the main body 380, and the two-groove groove 1
It fits in the grooves 16 and 18 of 0. 384 is a window,
The optical fiber 20 is guided to the grooves 16 and 18 through this.

(4) The optical fibers 20 are gathered and the holding tape 22 is wound to form a unit 24, and the take-up device 42 is used.
It winds up to the winding device 44 through (FIG. 1). At this time, the take-up device 42 and the take-up device 44 rotate in the direction of arrow 43. As a result, the twist of the tension member 12 is released, the groove body 14 is twisted, and the grooves 16 and 18 and the optical fiber 20 therein become spiral. (5) The range in which the groove main body 14 is twisted is such that the claws 382 are formed in the grooves 16 and 18 in the collecting device 38.
1 is on the right side of the collecting device 38 in FIG. 1 and does not extend to the left side.

[Case of Slot Type] In this case as well, the slot 11 having the spiral groove 15 can be manufactured in the same manner as in the case of the two groove groove type.

[0013]

【The invention's effect】

(1) Since the central tension member is continuously fed out in a twisted state and the main body of the groove or the slot having the straight groove is extruded thereon, it is not necessary to rotate the die unlike the conventional case. , Facilitating the manufacture of the groove or slot body. Further, the dimensional accuracy of the groove is improved and the manufacturing speed is increased. (2) Since the optical fiber can be housed in the straight groove, there is no need for high control of the device, and the equipment is inexpensive. (3) Since the two-groove groove 10 or the slot 11 can be manufactured and the optical fibers can be assembled in tandem, an inexpensive optical cable can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of an apparatus for manufacturing a unit 24 using the method of the present invention.

FIG. 2 is an explanatory view of a collecting device 38 of devices for manufacturing the unit 24 using the method of the present invention.

FIG. 3 is an explanatory view of a two-groove groove type optical cable (common to the present invention and the prior art).

FIG. 4 is an explanatory view of a conventional assembly of optical fibers.

FIG. 5 is an explanatory view of a slot type optical cable (common to the present invention and the prior art).

[Explanation of symbols]

 10 2 groove groove 11 slot 12 and 13 center tension member 14 and 17 main body 15, 16 and 18 spiral groove 19 and 24 unit 20 optical fiber 21 and 26 optical cable 22 holding tape 30 feeding device 32 extruder 34 cooling device 36 feeding Device 38 Collecting device 380 Main body 382 Claw 384 Window 40 Tape winding device 42 Pulling device 44 Winding device

Claims (1)

[Claims] 1. A method of manufacturing an optical cable, which comprises a step of forming an optical fiber unit by accommodating an optical fiber in the spiral groove of a groove or slot having a tension member in the center and having a spiral groove. In the above, the central tension member is continuously fed in a twisted state, and the main body of the groove or slot having a straight groove is extruded on the central tension member, and thereafter, the twist of the tension member is released and the groove or A method of manufacturing an optical cable, wherein a groove or slot having a spiral groove is formed by spirally deforming the straight groove while the body of the slot is twisted.