JP2833982B2 - Submarine cable - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a submarine cable for communication and power use, which is laid on the sea floor, one end of which is pulled up on land and stopped at a shore by a stopper.

[0002]

2. Description of the Related Art Conventionally, a submarine cable pulled up from the seabed to land is moored and fixed to a stopper driven into the seashore so that the submarine cable is not drawn into the sea due to a change in the seafloor topography. . In addition, a submarine cable from the coast to a depth of 500 to 1000 m is buried in the seabed because the submarine cable may be caught by fishing or the like and may be injured. However, on the seabed near the coast, particularly on sandy land, the movement of sand due to tides and the like easily occurs, and the phenomenon that the buried submarine cable is sometimes exposed is likely to occur.

Regarding the exposure of the submarine cable, it has been found that the conventional method of anchoring the submarine cable at the coast itself may be defective. FIG. 3 is a side view showing the submarine cable buried and retained by the conventional method. When the submarine cable 1 fixed by the first stopper 2 moves due to the movement of sand, the original position shown by the broken line. The tension increases with the deviation. When the tension of the cable 1 increases, the cable moves in the vertical direction, and the submarine cable 1 moves from the original state shown by the broken line to the position shown by the dashed line (the moved cable 8), and as a result, is exposed on the sea floor. Will be.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent such undersea movements from increasing the tension of a submarine cable and thereby exposing buried cables to the seabed. It is in.

[0005]

A submarine cable according to the present invention is laid on the seabed, at least one end of which is pulled up on the shore at the seashore, and has a communication or power supply stopped by a first stopper installed on the shore. In a submarine cable for use, a cable surplus portion which is stopped by a second stopper installed on the seabed and has a meandering shape is provided between the first and second stoppers. .

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the present invention.
FIG. 2 shows a side view thereof. The submarine cable 1 is first stopped by the second stopper 3 from the deep sea, and keeps the tension from the deep sea part direction. Usually, it is effective to install the second stopper 3 at a depth of 10 m or less, at which the main cable laying ship approaches the shore. Next, the submarine cable 1 rises from the seabed to land via an S-shaped extra cable portion, and is again stopped by the first stopper 2. Finally, it enters Beach Manhole 5 and enters a nearby submarine cable office.

In this embodiment, it is assumed that the submarine topography has moved and the submarine cable 1 has moved to the position indicated by the dashed line in FIG. At this time, the extra cable length 4 indicated by the solid line is completely extended, and the tension of the submarine cable 1 hardly increases.
Accordingly, in FIG. 2, the submarine cable 1 is buried in the state shown by the broken line. Further, when the submarine topography moves and tension is applied to the submarine cable 1, the submarine cable 1 moves to the position indicated by the one-dot chain line in FIG. 2 (the moved cable 8). Nevertheless, since the first stopper 3 is buried at a position lower than the sea level at low tide, the possibility of being exposed upward from the sea floor is extremely reduced.

[0009]

As described above, according to the present invention, in addition to the first land stopper, the second stopper is installed on the seabed, and the extra cable length is provided between the first and second stoppers. By burying the first stopper below the sea level at low tide together with the provision of the first stopper, it is possible to prevent the buried submarine cable from being exposed to the sea floor even when the cable moves along with the movement of the seabed terrain.

[Brief description of the drawings]

FIG. 1 is a plan view of one embodiment of the present invention.

FIG. 2 is a side view of one embodiment of the present invention.

FIG. 3 is a side view showing a state where a conventional submarine cable is laid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Submarine cable 2 First stopper 3 Second stopper 4 Extra cable length 5 Beach manhole 6 Land section 7 Submarine section 8 Cable after moving

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-51-125896 (JP, A) JP-A-5-209969 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02G 9/00-9/12

Claims (2)

(57) [Claims] 1. A first cable laid on the seabed, at least one end of which is lifted up on the seashore and installed on the land.
A submarine cable for communication or electric power stopped by a stopper, wherein the cable surplus length is stopped by a second stopper installed on the seabed, and has a meandering shape between the first and second stoppers. Submarine cable characterized by having a section. 2. The submarine cable according to claim 1, wherein the second stopper is buried at a submarine location lower than the sea level at low tide.