JPH08275368A - Y-forked joint - Google Patents

Abstract

PURPOSE: To miniaturize an inner conductor both in length direction and in width direction so as to miniaturize a joint by providing an approximately triangular inner conductor with a recess in the vicinity of the top of the triangular prism. CONSTITUTION: A Y-forked joint J1 for connecting the conductor 1a, 2a, and 3a of power cables 1, 2, and 3 is one in which the conductor 1a is to be inserted from one side and the conductor 2a and 3a is to be inserted from the other side, and this is equipped with connectors 17, where the conductors 1a, 2s, and 3a are inserted, respectively, and an inner conductor 19 which has recesses 18 with which to engage each connector 17. The inner conductor 19 is roughly in the shape of a triangular prism, and the recesses 18 with which to egage the connectors 17 wherein the conductors 1a, 2a, and 3a of the power cables to be connected are inserted, respectively, are provided in the vicinity of the top of the triangular prism. Therefore, the width in diametrical direction of the cable of the inner conductor 19 can be shortened less than conventional width. What is more, the length will do so long as it is as long as before. Therefore, the cable of an epoxy mold unit 21 wherein the inner conductor 19 is buried can be shortened both in longitudinal direction and in diametrical direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Y-branch joint, and more particularly to a miniaturized Y-branch joint.

[0002]

2. Description of the Related Art Conventionally, CV cables using crosslinked polyethylene as an insulator have been used for high voltage power cables of 66 kV or more because they have improved heat resistance and excellent corona resistance. A prefabricated joint is used to connect such a CV cable. If a prefabricated joint is used, the work at the site is only the work of combining the parts, the work efficiency is good, and the stable connection with less variation is made, so that it is applied to the straight connection, the branch connection, the unprocessed end, etc.

Of these, the Y-branch joint J is a joint for connecting the power cables 1, 2 and 3 as shown in FIG. 6, and the conductors 1a and 2a are exposed by peeling off the coating at the ends of the cables. The conductors 4a and 3a are connected to each other through the connector 4 inserted from one surface of the conductor 1a and the other surface of the conductors 2a and 3a, respectively. Then, the stress cone 7 into which the end of each cable is inserted is fitted to the fitting portion 9 of the epoxy mold unit 8 in which the internal conductor 6 is embedded. The inner diameter of the stress cone 7 through which the end portion of the cable penetrates is smaller than the outer diameter of the coating of the cable, and the taper portion of the outer periphery of the stress cone 7 is formed larger than the fitting portion 9 of the epoxy mold unit 8. It is designed to press the interface between the stress cone 7 and the coating of the cable and the interface with the epoxy mold unit 8 by being pressed by 10 to adjust the stress of the interface, prevent dielectric breakdown and fix the cable. It is supposed to do. The stress cone compression device 10 is protected by a protective fitting 11, and the epoxy mold unit 8 is housed and protected in a case 12.

[0004]

However, such Y
As shown in FIG. 7, the AA cross section of the inner conductor 6 that connects the conductors of the cables of the branch joint is shown in FIG.
The recesses 5 into which the connectors 4 into which a and 3a are respectively inserted are inserted are arranged in one row, and the width a of the inner conductor 6 is equal to that of the conductor 1.
It is necessary to have a length in which a, 2a, and 3a are arranged in parallel, and further, it is necessary to fix each cable from both left and right directions, and a predetermined length 1 (FIG. 6) is necessary. Therefore, the epoxy mold unit 8 in which such an internal conductor 6 is embedded also becomes large in the radial direction of the cable, and the length of the length d becomes large due to the fixation of the stress cone 7 which is fitted from both left and right directions. .

Therefore, as shown in FIG.
There was one in which 3 had an M-shaped cross section. Even if the recessed portion 5 for fitting the connector 4 into which the conductor is fitted is formed from the left and right by making the inner conductor 13 have the M-shaped section, the length of the inner conductor 13 is such that the recessed portion 5 is formed in only one direction. The length l ₁ of the inner conductor 13 can be made shorter than the conventional one. As the length of the inner conductor 13 becomes shorter, the thickness of the epoxy mold unit necessary for insulation becomes thinner. Therefore, the length of the epoxy mold unit is shortened, and some joints are shortened in the length direction.

However, such an internal conductor 13
Had the same width a as the inner conductor 6 shown in FIG. 7, and it was not possible to shorten the cable in the radial direction. Therefore,
The radial direction of the epoxy mold unit was not shortened either. The present invention has been made to solve the above-mentioned drawbacks, and can reduce the size of the joint in the length direction and the width direction of the internal conductor, and can reduce the size of the joint.
The purpose is to provide a branch joint.

[0007]

In order to achieve the above object, a Y-branch joint of the present invention includes a mold unit and a conductor that is embedded in the mold unit and is exposed by peeling off the coating of the end portions of the three cables. In a Y-branch joint provided with an internal conductor having a recessed portion for inserting and connecting each and a stress cone penetrating a cable and fitted into a mold unit, the internal conductor is a substantially triangular prism, and the recessed portion Is provided near the apex of the triangular prism.

[0008]

[Function] The inner conductor has a triangular prism shape. In the vicinity of each apex of the triangular prism, a recess is formed to connect the conductor exposed by peeling off the coating on the end of the cable. Therefore, it is possible to shorten the length and width of the inner conductor as compared with the conventional inner conductor in which the recesses for connecting the three cables are provided in one row, and the inner conductor can be downsized. Therefore, since the epoxy mold unit may be small, the joint can be downsized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment to which the Y-branch joint of the present invention is applied will be described with reference to the drawings. As shown in FIG. 1, the Y-branch joint J1 is a 66 kV CV power cable 1,
It is a prefabricated joint that connects a few conductors 1a, 2a, 3a. Here, the power cable 1 (same for 2, 3) is provided with an insulator 13 made of cross-linked polyethylene on a conductor 1a via a semiconductive layer, and a semiconductive tape for preventing corona discharge on the upper layer. A shield layer 15 made of a braided copper wire or the like is provided as an earth layer on the wound 14 layer, and an insulating coating 16 is further provided on the outer periphery thereof.

In the Y-branch joint J1 for connecting the conductors 1a, 2a, 3a exposed by peeling off the coating on the ends of the power cables 1, 2, 3 as described above, the conductor 1a is on one side and the conductors 2a, 3a are on the other side. Inserted from the surface, conductor 1
The inner conductor 19 is provided with the connectors 17 into which a, 2a, and 3a are respectively inserted, and the recesses 18 into which the respective connectors 17 are fitted. The connector 17 is the recess 1
It is fixed to the connector 8 by a connector tightening fitting 20 so as not to be pulled out. The inner conductor 19 is an epoxy mold unit 21.
It is formed by being molded inside. Further, the fitting portion 22 of the epoxy mold unit 21 has a through hole having an inner diameter smaller than the outer diameter of the insulator 13 from which the outer peripheral layers other than the semiconductive tape 14 of the power cables 1, 2, 3 are removed. A spindle-shaped stress cone 23 having a hole is fitted into the through hole through the insulator 13. Stress cone 23
Is pressed by the stress cone compression device 24 using the collar 25 provided at the end of the inner conductor 19 as a stopper to load the interface between the insulator 13 of the power cable and the epoxy mold unit 21 to prevent dielectric breakdown. ing. Further, a protective metal fitting 26 is provided to protect the portion of the power cable from which the coating has been peeled off, and is connected to the case 27 that covers the epoxy mold unit 21 to protect the connection portion and also a protective cover provided on the outer periphery thereof. To be fully prepared. The shield layer 15 is connected to the shield layer of another power cable via the stress cone compression device 24, the protective metal fitting 26, and the case 27.

As shown in FIG. 2, the inner conductor 19 of such a Y-branch joint J1 has a substantially triangular prism shape, and the connectors 17 into which the conductors 1a, 2a, 3a of the power cables to be connected are respectively inserted are fitted. The matching recessed portion 18 is provided near the apex of the triangular prism. Therefore, as shown in FIG. 3, the width a ₁ of the inner conductor 19 in the radial direction of the cable is the same as the conventional width a ₁ in which the three recessed portions 18 of the power cable are provided in one row.
(Fig. 7) It can be made shorter. Moreover, the length l ₂
Also, the length may be the same as the length l _{1 of the} conventional M-type inner conductor. Therefore, the longitudinal direction and the radial direction of the cable of the epoxy mold unit 21 in which the inner conductor 19 is embedded can be shortened, and the Y-branch joint J1 can be made smaller than the conventional Y-branch joint.

The Y-branch joint J1 having the above structure
In order to connect the CV power cable using, the conductor 1a exposed by peeling off the coating at the end of the cable from one direction,
The conductors 2a and 3a are respectively inserted into the connectors 17 from other directions, the connectors 17 are fitted into the internal conductors 19 embedded in the epoxy mold unit 21, and the connector fastening metal fittings 20 are tightened to fix the conductors. After that, the stress cone 23 in which the cable has been inserted in advance is arranged at the cable end, the stress cone compression device 24 is set, and the stress cone 23 is pressed so that the interface between the insulator 13 of the cable and the epoxy mold unit 21 is removed. Try to load. After that, the protective metal fitting 26, the case 27 and the protective cover are set. By doing so, the work at the site is easy and the connection with a constant electric property can be performed.

Although the above description has described connection of a single-phase power cable, in the case of laying multiple power cables, for example, three-core power cables, as shown in FIG. 4, a Y-branch joint J1 is provided for each three-core power cable. And the Y-branch joints J1 are arranged in a bale stack or arranged in a line as shown in FIG. Since the small Y-branch joint is used, the connecting portion can be made very compact.

[0014]

As is clear from the above description, according to the Y-branch joint of the present invention, the inner conductor is formed in a substantially triangular shape, and the recessed portions of the three conductors are provided near the apex of the triangular prism. Since the width of the cable in the radial direction can be reduced and the length in the longitudinal direction can also be reduced, the joint can be downsized.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a main part of the embodiment shown in FIG.

FIG. 3 is a side view showing a main part of the embodiment shown in FIG.

FIG. 4 is a sectional view showing another embodiment.

FIG. 5 is a sectional view showing another embodiment.

FIG. 6 is a sectional view showing a conventional example.

FIG. 7 is a sectional view showing a conventional example.

FIG. 8 is a sectional view showing a conventional example.

[Explanation of symbols]

1, 2, 3 ... Power cable 1a, 2a, 3a ... Conductor 18 ... Recessed portion 19 ... Inner conductor 21 ... Mold unit (epoxy mold unit) 23 ... Stress cone J1. ‥‥ Y branch joint

Claims (1)

[Claims] 1. A cable comprising: a mold unit; an internal conductor embedded in the mold unit; and an internal conductor having a recessed portion for inserting and connecting conductors exposed by peeling off coatings at the end portions of three cables. In a Y-branch joint having a stress cone that penetrates through the mold unit and is fitted into the mold unit, the internal conductor is a substantially triangular prism, and the recessed portion is provided near the apex of the triangular prism. Branch joint.