JPS61221508A - Method and section for connecting communication cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a communication cable connection method and a connection unit used, for example, to connect communication cables containing gas sealed with pressurized gas.

[Prior art and its problems]

In communication cables that require gas maintenance, pressurized air or nitrogen gas is sealed inside the cables, so it is necessary to prevent gas leakage from the connections. Conventionally, methods for constructing the above-mentioned double-pull connections include airtight construction methods such as the auxiliary lead pipe construction method that uses heat, the GS cable construction method, the heating wire fusion construction method, the see-through fusion construction method, or purely mechanical methods. Airtight construction methods using sealing tape are used.

However, these conventional airtight cable connection methods require complicated methods such as using heat or winding multiple layers of highly adhesive sealing tape, resulting in poor workability. Moreover, it is impossible to dismantle the sealing part for reconnection, or it is extremely complicated. Furthermore, there are construction methods that use non-adhesive rubber backing to compensate for these drawbacks of the conventional method, but in both cases, the flow of the sealing material and the expansion of the auxiliary lead pipe can cause sealing failures, so the connection may become damaged over a long period of time. There were disadvantages such as a lack of reliability, such as poor airtightness and gas leaks.

[Purpose of the invention]

This invention was made in view of the above circumstances, and has a simple structure, easy connection, and highly reliable communication that does not deteriorate airtightness due to flow of sealing material or expansion of auxiliary lead pipes. The object of the present invention is to provide a cable connection method and a connection part.

[Structure of the invention]

When connecting a cable such as a gas-filled cable filled with pressurized gas, the present invention provides an end surface member made of an elastic material at both ends of a connection case that covers the conductor connection point of the cable, and Expanding the end member with gas pressure inside the box and pressurizing the sealing material to bring it into close contact with at least one of the cable jacket and the connection box 1
．． 1: The connection case is characterized in that the inside of the connection case is hermetically sealed.

〔Example〕

FIGS. 1 and 2 show an example of a communication cable connection section of the present invention.

1 and 2, each conductor 2, 2, . . . of the communication cable 1 to be connected is connected to each conductor of a mating cable (not shown) at a conductor connection point 3, respectively. A pair of end face members 5 (the one on the other cable jacket is not shown) are disposed facing each other on the jacket 4 of the cable 1 with the conductor connection point 3 in between.

The end member 5 has a substantially disk-like appearance and is formed by integrally bonding semi-disc-shaped half bodies 6.6 made of an elastic material having a large amount of elastic deformation such as rubber or plastic. Here, a through hole 7 having an inner diameter slightly larger than the outer diameter of the cable 1 is bored along the axial direction in the center of the facing surface of the half body 6.6 located at the center of the end face member 5. It is set up.

Further, a plurality (four in the figure) of annular full portions 8 are formed along the circumferential direction on the inner circumferential surface of the through hole 7 of the half bodies 6, 6. Further, at both peripheral edges of the through hole 7 of the half body 6.6, half small cylindrical flanges 9 extend outward along the axial direction by a predetermined length and face each other.
are formed respectively. The half bodies 6, 6 are each disposed oppositely on the outer sheath 4 of the cable 1 via an adhesive sealing material 10 such as an unvulcanized rubber tape wound around the outer sheath 4 of the cable 1, They are integrally connected by bolts 11 and nuts 12 provided on the respective flanges 9.

Moreover, on the surface 13 of the half body 6.6 of the end face member 5,
Four parts each having a predetermined depth and having a sector-shaped cross-section are formed along the surface 13, and the recessed parts form thin-walled parts 23 on the inner and outer peripheries of the half-split body 6. Furthermore, a thickened portion 24 is formed on one end surface of the half body 6. In addition, due to these recesses, there is a hollow space (hollow part) 1 inside each part.
4°14 is formed. Further, a plurality (four in the figure) of annular protrusions 15 are formed along the circumferential direction on the outer circumferential surface of the half bodies 6, 6 of the end face member 5.

Here, the end face member 5 on which the protrusions 15 are formed
A sealing material 16 similar to the sealing material 10 described above is also wound around the outer periphery. A connection case 17 is provided on the outer periphery of the end face member 5 with the sealing material 16 interposed therebetween.

The connection box 17 has a substantially cylindrical appearance, and is divided into two halves 18 along the axial direction by bolts 19.
. . . and nuts 20, . . . At the end of the connection box 17 and at a position slightly longer than the width of the end member 5 along the longitudinal direction from this end, an annular shape protruding radially inward is provided. Locking protrusions 21, 21 are formed. The connection case 17 is connected to the locking protrusion 2.
It is attached to the outer circumference of the end face member 5 so that the outer circumference of the end face member 5 is sandwiched between 1 and 21. Further, the other end (not shown) of the connection case 17 is similarly attached to the outer periphery of an end member provided on the other cable jacket. As a result, the connection case 1
A space 22 closed by the connection case 17 and the end face member 5 is formed around the conductor connection point 3 covered by the conductor connection point 3 .

In the communication cable connection section configured in this manner, when gas for gas maintenance is pressurized and sealed into the cable 1, the outer sheath 4 is peeled off and the above-mentioned space 22 is also connected to the above-mentioned space 22 through the exposed conductor connection section 3. Since it is filled with gas, the connection box 1
The inside of the cable 7 is pressurized to the same pressure as the inside of the cable 1. Then, the gas pressure inside the connection box 17 acts on the end member 5 from the space 14 in the end member 5 as shown by the arrow in FIG. Expand towards the direction. For this reason, the protrusions 8..., 15... formed on the inner and outer circumferential surfaces of the end face member 5 have sealing materials 10, 16, respectively.
The cable 1 is tightly attached to the outer sheath 4 of the cable 1 and the inner peripheral surface of the connection case 17 through the cable 1, so that the inside of the connection case 17 is kept airtight.

According to such communication cable connection portion and connection method, the thin wall portion 23 of the end face member 5 expands due to the gas pressure inside the connection case 17, thereby airtightly sealing the inside of the connection case 17. Therefore, high airtightness can be maintained. In addition, the structure is extremely simple and it is easy to remove, so that the cable 1 can be easily reconnected. Furthermore, annular protrusions 8..., 1 are formed on the inner and outer circumferential surfaces of the end face member 5.
5..., the sealing effect between the contact surface and the contact surface is increased, and therefore higher airtightness can be obtained.

(Experimental Example) FIG. 3 is a graph showing the results of an experiment conducted to confirm the effects of the present invention.

In this experiment, an aluminum pipe with a pressure sensor built into its surface was used instead of a cable, and a cable connection using the conventional auxiliary lead pipe construction method and a cable connection according to the present invention were simulated on the outer circumference of the aluminum pipe. The degree of adhesion to the outer periphery of the aluminum pipe at each of the connecting portions was measured as a pressure value using the pressure sensor.

In FIG. 3, the horizontal axis represents the passage of time, and the vertical axis changes according to the passage of time. This shows the measured value of the F pressure distribution sensor.

However, A in the figure shows the conventional auxiliary lead pipe construction method, and the pressure change at the outer periphery of the pipe after the auxiliary lead pipe is crimped with a sealing tape on the outer periphery of the pipe with an initial crimping force of about 15 kgf/aI. This shows that.

In addition, B in the figure shows the connection part according to the present invention, point b1 indicates the time of bolt tightening of the end face member, point b2 indicates the time of bolt tightening of the connection case, and point b3 indicates the time of bolt tightening of the connection case. is the maintenance gas (approximately 1Kg f/ci) into the connection case.
The figures show the times when the samples were encapsulated under pressure.

As is clear from the graph shown in Figure 3, in the conventional connection shown in the figure, the adhesion pressure to the outer circumference of the pipe gradually decreases over time due to fitting in of the lead pipe, etc. Maintaining airtightness within the joint must rely solely on the adhesive strength of the sealing tape. On the other hand, in the case of the present invention, even if the bolt tightening force decreases due to the fitting of the bolt tightening part, the maintenance gas pressure in the connection part expands the end face member toward its inner and outer periphery. It can be seen that in order to press the pipe, the end face member always comes into close contact with the outer circumferential portion of the pipe at a pressure P substantially corresponding to the maintenance gas pressure, so that the airtightness does not deteriorate over time.

In the above embodiment, the end face member 5 is provided with four parts to form the cavity (cavity part) 14, but the invention is not limited to this. For example, as shown in FIG.
The cavity (cavity part) 27 may be formed by providing an arc shape along the outer periphery of the cable piece.

Further, protrusions 8 and 1 formed on the inner and outer circumferential surfaces of the end face member 5
The cross section 5 is not limited to a semicircular cross section, but may be a V-shaped cross section or an opening-shaped cross section.

〔Effect of the invention〕

As explained above, in the communication cable connection method and connection part of the present invention, the thin inner and outer circumferential parts of the end face member expand in the radial direction due to the gas pressure inside the connection case, thereby making the inside of the connection case airtight. Since the airtightness is sealed, high airtightness can be maintained without deterioration of airtightness. Furthermore, the structure is extremely simple, and since it is easy to remove as well as remove, cables can be easily reconnected. Furthermore, if an annular protrusion along the circumferential direction is provided on the inner circumferential surface or outer circumferential surface of the end face member, the sealing effect can be further increased.

[Brief explanation of drawings]

1 and 2 show an embodiment of the connection part of the communication cable of the present invention, FIG. 1 is a side sectional view of the main part, and FIG. FIG. 3 is a graph showing the results of an experimental example to confirm the effects of the present invention, and FIG. 4 is a side sectional view showing another example. 1...Cable, 3...Conductor connection point, 4...Outer cover, 5...End member, 8,
15... Protrusion, 10° 16... Sealing material, 14... Hollow space (cavity), 17...
- Connection box, 23...thin wall part.

Claims (4)

[Claims] (1) A connection box is provided covering the conductor connection points of the cables to be connected to each other, and end members made of an elastic body are attached to both ends of the case, and the pressure of the gas supplied into the connection case is and the end face member is expanded primarily in the radial direction to bring it into close contact with at least one of the outer sheath of the cable and the connection case, thereby airtightly sealing the space between the connection case and the cable sheath. A communication cable connection method characterized by: (2) A sealing material is interposed between the cable sheath and the end member or between the end member and the connection box, and the sealing material is pressed by expansion of the end member. How to connect the communication cable described in Section 1. (3) It has a cylindrical connection box that covers the conductor connection point of the cable, and an end face member made of an elastic body attached to both ends of the connection box, and the end face member includes a connection box. A connection part for a communication cable, characterized in that a hollow part communicating with the inside of the communication cable is formed. (4) The communication cable connection portion according to claim 2, wherein the end face member has an annular protrusion along the circumferential direction of at least one of an inner circumferential surface and an outer circumferential surface.