JPS6257965B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a retaining structure for retaining an aluminum feed line type submarine optical cable to a coupling part of a connecting box or a repeater.

[Background technology and its problems]

FIG. 1 is a cross-sectional view showing an example of a submarine optical cable in which aluminum or aluminum alloy can be used as a power supply line, in which 1 is an optical fiber unit formed by collecting optical fiber cores 1a, and 2 is the optical fiber unit. 1 is a pressure-resistant layer that protects the tensile strength members 3 and 4, and 5 is a pressure-resistant pipe that covers the tensile strength members 3 and 4. The pressure-resistant pipe 5 also serves as a power connection path. It is made of aluminum or aluminum alloy. 6 and 7 are PE (polyethylene) jackets forming an insulating layer.

FIG. 2 shows a restraining structure for connecting such an aluminum feed line type submarine optical cable to a connection box or a coupling of a repeater, and the same parts as in FIG. 1 are designated by the same reference numerals.

In this figure, 10 is a pressure-resistant tube that protects the connecting portion of the optical fiber, 11 is an insulating coating layer made of polyethylene, etc., 12 is a metal cover,
13 is an anchor disc. The through hole of this anchor disk 13 is formed in a tapered shape, and the tensile strength members 3, 4 are held back by a taper pin 14, as is well known.

Reference numeral 15 designates a retaining part made of a conductive material that is electrically connected to the anchor disk 13, and this retaining part 15 is fixed to the pressure-resistant pipe 5 of the submarine optical cable, as will be described later.

Note that 16 indicates a rubber boot portion.

According to this anchoring structure, submarine optical cables are
The tensile strength members 3 and 4 are held in place by the anchor disk 13, and then the optical fiber core wire 1a drawn out inside the pressure tube 10 is connected to another optical fiber.

Then, the pressure-resistant pipe 5 and the retaining component 15 are connected to ensure a conductive path for supplying current to a repeater or the like.

In this case, normally, point A on the inner peripheral side of the retaining part 15 is first mechanically connected to the pressure-resistant pipe 5 using an adhesive or the like, and then the retaining part 15 and the pressure-resistant pipe 5 are further connected to each other in order to ensure conductivity. It is conceivable to make an electrical connection by soldering at point B.

However, this method of connecting the pressure-resistant pipes 5 has the following drawbacks.

When the retaining component 15 and the pressure-resistant pipe 5 are connected by soldering, the adhesive at point A is thermally degraded by the heat generated during the soldering process, resulting in a decrease in adhesive strength. Further, even when point A is fixed by mechanical compression, for example, the strength of this compression bonded portion is reduced due to the cycle of thermal expansion and contraction.

Incidentally, the above-mentioned anchor disk 13 is responsible for the tensile force applied during work such as laying and salvaging the submarine optical cable, but the pressure-resistant pipe 5 also receives a tensile force corresponding to the elongation rigidity of the cable. As mentioned above, when the mechanical holding force at point A decreases, a slip occurs between points A and B, and as a result, the soldered connection at point B breaks, causing a problem in which a good power supply path cannot be secured. do.

The use of flux is essential for aluminum soldering work at point B, but since it is difficult to completely remove the residue after soldering, the connection at point B may corrode over time and cause failures. cause it to happen.

The above-mentioned problem can be solved by keeping a sufficient distance between points A and B so that they are not affected by heat, but in this case, the length of the connecting box itself will inevitably become longer, and the length of the connecting box will increase. Bending performance deteriorates.
In addition, the amount of materials used increases, causing an increase in costs.

[Purpose of the invention]

This invention provides a detention structure for an aluminum power feed line type submarine optical cable that uses ultrasonic welding to solve the problem of such a detention structure and can ensure the reliability of the submarine optical cable feed path. .

〔Example〕

FIG. 3 shows the connecting part between the retaining part 15 and the pressure-resistant pipe 5, which are the main parts of the retaining structure of the present invention, and the same reference numerals as in FIG. 2 indicate the same parts.

In this figure, reference numeral 15 indicates a retaining part made of aluminum alloy, and a pressure-resistant pipe 5 made of aluminum or aluminum alloy is inserted into its through hole.

In this case, the mechanical connection means is the retaining part 15.
This is done by adhesive applied to the inner circumferential surface of the retaining part 15 and the outer circumference of the pressure-resistant pipe 5, and the electrical connection means is made by pressing an ultrasonic horn to several points P on the outer circumferential surface of the tip of the retaining part 15. Internal pressure-resistant pipe 5 and retaining parts 1
5 are connected by ultrasonic welding.

As is well known, ultrasonic welding is a method of welding by concentrating ultrasonic energy on the parts to be welded, but this ultrasonic welding generates almost no welding heat and can be done in a short time. be able to.

Therefore, there is almost no deterioration of the adhesive due to heat, as seen in soldered connections, and the mechanical strength of the connection does not decrease.

FIG. 4 shows still another embodiment of the present invention, in which the retaining member 15 has a structure in which the tip portion is separated into a plurality of pieces by slits S ₁ and S ₂ as shown in the figure.

Then, similarly to FIG. 3, the inner circumferential surface of the retaining part 15 and the outer circumferential surface of the pressure-resistant pipe 5 are mechanically connected with adhesive, and point P in the divided tip region is ultrasonically welded. It is electrically connected to the pressure-resistant pipe 5.

In this case, the slit-like part has a buffering effect, so even if a slip of about 5 to 6 mm occurs in the adhesive layer due to the tensile strength of the cable applied during installation or repair, the electrical connection will be maintained. It is possible to effectively prevent the ultrasonic weld from being destroyed.

5 and 6 show still another embodiment of the present invention, in which the buffering effect is achieved by corrugated thin metal wires.
m ₁ , and a spirally wound metal wire m ₂
This is a concrete example.

In this case, the buffering effect is further improved, so the mechanical and electrical connections can be completely separated, and the conductivity of the electrical ultrasonic weld remains even when subjected to cable tension. It will not be damaged.

In the above embodiments, the case where an adhesive is used as the mechanical connection means has been described, but a pressure bonding means such as caulking may also be used.

〔Effect of the invention〕

As explained above, the anchoring structure of the aluminum feed line type submarine optical cable of the present invention uses ultrasonic welding as both a mechanical connection means and an electrical connection means for connecting the pressure-resistant pipe and the anchoring parts of the submarine optical cable. This has the advantage that there is no reduction in mechanical adhesion due to heat, and at the same time, the reliability of electrical connections is improved.

In addition, when the mechanical connection points are separated via a buffer mechanism, the electrically bonded points will not be destroyed by ultrasonic welding even if the cable's tensile force is affected, which increases the reliability of the submarine optical cable network. This has the effect of improving.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of an aluminum feed line type submarine optical cable, Fig. 2 is a sectional view showing an example of connecting an aluminum feed line type submarine optical cable to a connection box or repeater coupling, Fig. 3 4 is a sectional view showing the main part of a restraining structure which is an embodiment of this invention, FIG. 4 is a sectional view of the main part which is another embodiment of this invention, and FIGS. FIG. 7 is a cross-sectional view of the main part of another embodiment. In the figure, 1 is an optical fiber unit, 2 is a pressure-resistant layer that protects the optical fiber unit, 3 and 4 are tensile strength members having a two-layer structure, 5 is a pressure-resistant pipe that covers the tensile strength members, 6, 7 is a polyethylene jacket forming an insulating layer, 10 is a pressure-resistant tube that protects the connecting portion of the optical fiber core, 11 is an insulating coating layer made of polyethylene, etc., 12 is a metal cover, and 13 is an anchor disc. , 14 is a taper pin,
15 is a retaining part, 16 is a rubber boot, P is an electrical bonding point on the outer peripheral surface of the tip of the retaining part, m ₁ is a corrugated thin metal wire, m ₂ is a spiral metal thin wire, S ₁ and S ₂ are the tips of the retaining part It is a slit.

Claims (1)

[Scope of Claims] 1. A submarine optical cable in which a tensile strength member is twisted around a pressure-resistant layer that protects an optical fiber unit, and a pressure-resistant pipe made of aluminum or aluminum alloy is coated around the outer periphery of the tensile strength member, which serves both as a pressure-resistant shell and a power supply path. In the retaining part that retains the connection box or the coupling part of the repeater, the connection between the retaining part coupled to the anchor disk retaining the tensile strength body and the pressure-resistant pipe is performed using electrical connection means using ultrasonic waves and adhesive. A restraining structure for an aluminum power feed line type submarine optical cable, characterized in that the connection is performed by mechanical connection means such as a chemical agent. 2. The aluminum feed line type according to claim 1, wherein the mechanical connection means and the position where the ultrasonic electrical connection means are applied are connected by a conductive buffer mechanism. Detention structure for submarine optical cables.