JP2536490Y2 - Cable air termination - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention relates to an air termination portion of a cable used for a lead wire or the like for a power application test to an electric device.

2. Description of the Related Art A detachable slip-on type cable head is used to connect a cable and a high-voltage electric device at the time of an electrical characteristic test or the like of the high-voltage electric device. Generally, an insulator type and an epoxy type are known as this type of cable head.

FIG. 6 shows an aerial terminal using an insulator type cable head.

In the figure, the cable terminal 1 is set up and terminated inside the insulator tube 40. The porcelain tube 40 is fixed on a bottom plate 41 or the like of the device, and a shield ring 42 is attached to a top portion thereof for electrical protection. Also, in order to protect the terminal processing section of the cable terminal 1, a protective fitting 43 is provided.
Is attached so as to cover the bottom of the insulator tube 40. Insulation pipe
Numeral 40 is placed in an insulating gas atmosphere (not shown) filled in the device.

However, as shown in FIG. 6, the cable aerial end portion having such a configuration is configured such that the cable terminal 1 is bent and raised on the floor surface 44 and inserted into the insulator 40. There is a space problem that the height H between the bottom plate 41 and the floor surface 44 of the device cannot be reduced below a certain level. In such a case, it is preferable to employ a T-branch air terminal portion as shown in FIG.

The aerial terminal portion shown in FIG. 7 uses an epoxy type cable head, and the body portion 60 and the bushing 63 are integrally formed by epoxy molding. That is, in the figure, the cable 50 is stripped off at its end,
51 and conductor 52 are exposed. In addition, a mold stress cone 53 is put on the outer periphery of the insulator 51 for insulation reinforcement, and a constant pressing force is applied by a press fitting 54. Further, a protective case 55 is provided to cover and protect the cable terminal.

On the other hand, the left side of the main body 60 is hermetically sealed by a blind line 56 in this example. The conductor 52 of the cable is fitted into the female base 61a of the guide rod 61. Further, a bell mouth 62 is provided at the base of the bushing 63 to alleviate the electric field in a portion surrounding the guide rod 61.

The aerial end portion having such a configuration is provided with a bushing 63 in a direction perpendicular to the direction of the cable 50 and can be attached to a device or the like, so that the space problem described with reference to FIG. 6 is solved. be able to.

(Problems to be Solved by the Invention) However, since the T-branch air terminal section as shown in FIG. 7 is manufactured by using an epoxy resin mold, it can be used outdoors or a relatively high voltage is applied. If it is used for a part that has a problem, there is a problem in insulation properties. That is, a bushing made of an epoxy resin is inferior in tracking resistance as compared with an insulator tube made of an insulator, so that it is difficult to use it outdoors.

The present invention has been made in consideration of the above points, and it is possible to sufficiently reduce the distance between the device and the floor surface, and also, in terms of electrical characteristics, use a cable which can withstand outdoor use. It is intended to provide a middle termination.

(Means for Solving the Problems) The cable end portion of the cable according to the present invention is a resin-molded branch bushing into which the end of a cable for branch connection is inserted, and is formed integrally with the branch bushing. A male base extending in a direction perpendicular to the cable insertion direction, and a guide rod embedded in the branch bushing, electrically connected to the cable terminal, and protruding by a length dimension connectable from the male base. A porcelain air-termination insulator tube having a receiving portion in which the male base is disposed, and a conductor pull-out bar disposed in the insulator tube and electrically connected to the conductive rod, wherein the branch bushing is It is characterized in that it is directly fixed to the porcelain tube via fixing means.

(Operation) The above-described cable aerial terminal section realizes the same configuration as the conventional epoxy type T-branch aerial terminal section by a resin mold type branch bushing. On the other hand, by fitting the male base of the branch bushing into the receiving portion of the porcelain insulator tube for aerial termination, an aerial termination with good tracking resistance is formed. By the combination of the two, the distance from the floor surface can be kept relatively small, and a cable aerial terminal having good electric characteristics can be formed.

(Embodiment) Hereinafter, the present invention will be described in detail with reference to the embodiment shown in the drawings.

FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of a cable aerial terminal part of the present invention.

In the figure, the cable end portion has a branch bushing 2 made of resin such as epoxy for receiving the cable terminal 1 and a porcelain insulator tube 5 for air end receiving the male base 2a of the branch bushing 2. ing.

A guide rod 4 is embedded in the inside of the branch bushing 2, and its base has a T-branch configuration. The columnar portion penetrates through the male base 2 a of the branch bushing 2, and its tip is exposed to the outside. It is configured to be. Male base of branch bushing 2
2a is inserted into the receiving portion 6 of the insulator tube 5, and a shield ring 9 is attached to the top of the insulator tube 5. A conductor lead bar 7 is provided so as to penetrate the shield ring 9, and the conductor lead bar 7 is connected to the upper end of the guide rod 4 by compression at the lower end.

On the other hand, in the cable terminal 1, the sheath is peeled off, and the shielding tape 12 and the semiconductive layer 13 are exposed. The semiconductive layer 13
A semiconductive tape 14 of a predetermined length is wound from the end of the semiconductive tape 14 toward the outer periphery of the cable insulator 15. This cable terminal 1 is covered with a protective case 16 and the protective case
The left end of the cable terminal 1
Airtightly sealed. The right end of the protective case 16 is fastened and fixed to the side wall of the branch bushing 2 using a bolt 26.

On the other hand, a rubber mold stress cone 21 is mounted on the outer periphery of the cable insulator 15 and is fitted with a trumpet-shaped pressing fitting.
22 are arranged to press from left to right in the figure. The push fitting 22 is urged by a coil spring 25 that locks one end of the washer 24 engaged with the inner wall step of the protective case 16 and presses the push fitting 22 at the other end. The coil spring 25 is positioned by the bolt 23.

A wedge-shaped contact 18 is put on the cable conductor 20, and a male screw 27 fixed to the base of the branch bushing 2.
And the female screw 19 are tightened, gripped and fixed. As a result, an electrical and mechanical connection between the cable conductor 20 and the guide rod 4 is achieved.

The fixing between the branch bushing 2 and the porcelain pipe 5 is performed by a fixing member 8. This fixing member 8
For example, the configuration is as shown in FIG. 2 or FIG.

2 is a male base 2a of a branch bushing.
The base flange 8a is arranged so as to support the base of the porcelain tube 5 into which the base member 8 is inserted, and a mounting flange 8d is interposed between the shoulder of the male base 2a and the base flange 8a. The mounting flange 8d is provided with two through holes, the mounting flange 8d and the base flange 8a are integrated by a bolt 8c, and the mounting flange 8d and the male base 2a are integrated by a mounting bracket 8e and a bolt 8f. And are integrated. In addition, a packing 8g is inserted for an airtight seal therebetween.

Further, a conductive paint 10 is applied to the outer peripheral portion of the male base 2a to reduce electric stress. The conductive paint 10 is electrically connected to the mounting flange 8d, and is grounded via the base flange 8a.

In the case of adopting the above configuration, as shown in FIG. 1, there is no need to bend the cable terminal 1 below the insulator tube 5, and there is no space problem such as keeping the distance from the floor surface. . Further, since the porcelain insulator tube 5 is used for the aerial terminal itself, the withstand voltage characteristics are improved.

Further, in the case of such a configuration, it is possible to draw the cable in a π-type with one insulator, that is, to branch in the air, which is economical. Moreover, since the structure is not such that the cable is terminated inside the insulator tube, the processing length required for the terminal treatment of the cable can be extremely reduced.

Also, if a fixing member as shown in FIG. 2 is used,
The outer shape of the branch bushing 2 itself can be simplified, and molding can be facilitated. Therefore, electric characteristics are also easy. Of course, not only a T-type branch but also a plurality of branches such as a Y-type and an X-type are possible.

FIG. 3 shows a fixing member in which the mounting structure between the male base 2a and the insulator tube 5 is simplified.

The fixing member 8 shown in FIG. 3 has an embedded ground electrode 8b provided on the male base 2a. A bolt 8c passes through the ground electrode 8b, and is screwed into the base flange 8a. By doing so, the number of bolts is reduced, and the number of packings 8g is also reduced, which has the effect of simplifying the configuration.

By the way, when the branch bushing as described above is molded, if the length of the guide rod 4 is pulled out to the top of the insulator tube 5, the size becomes large, and the molding operation becomes complicated.

Therefore, as shown in FIG. 1, it is preferable to use a relatively short conductive rod 4 and to attach a conductor lead-out rod 7 to the insulator tube 5 in advance, so that both are electrically connected.

FIG. 4 is a longitudinal sectional view of the vicinity of the compression connection portion 7a of the conductive rod 4 and the conductor lead rod 7 of FIG. It is preferable that the compression connection point as shown in the drawing has a smooth structure so that the electric field does not concentrate.

Further, as shown in FIG. 5, a contact 7c made of a so-called multi-lamb band or the like may be attached to the tip of the conductive rod 4 so as to be connected to the conductor pull-out rod 7 in a plug-in manner. The multi-ram band has a large number of claws on its outer peripheral surface that bite into the conductor pull-out bar 7, and when the tip of the conductive bar 4 is inserted into the tip of the conductor pull-out bar 7, both are mechanically and electrically driven. It is of a configuration that is connected with a single touch.

In addition to the above-described embodiment, the conductive rod 4 and the conductor lead-out rod 7 are connected by any method such as a screwing type, a soldering type, a blade type, and a brazing type, which is widely used for detachable or permanent connection type electric connection. You can do it.

In this way, as shown in FIG. 1, it becomes easy to manufacture the guide rod 4 having a complicated shape for receiving the cable conductor 20 and the like at the base.

That is, since the rod body 4 is usually manufactured by casting or the like, the shorter the columnar portion of the base portion 4a, the easier the processing. Also, in the case of epoxy molding work,
Although the branch bushing is housed in the casting pot, the casting pot can be made smaller. Also, depending on the voltage, the insulator 5
In this case, the branch bushing 2 can be used in common.

(Effect of the Invention) The cable end portion of the cable of the present invention described above is provided with a resin-molded branch bushing for receiving a cable terminal, and the male base of the branch bushing is connected to the receiving portion of the porcelain insulator tube for the air end. Since the male base of the branch bushing is erected substantially perpendicular to the cable laying direction, there is an effect that a curved portion of the cable is not required. In addition, the aerial terminal is composed of a porcelain tube, and has good withstand voltage characteristics. In addition, since the bushing guide rod is electrically connected to the conductor pull-out rod inside the insulator tube, the branch bushing can be reduced in size and the assembly work and the like can be simplified.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a cable aerial end portion of the present invention, FIGS. 2 and 3 are longitudinal sectional views of a main part of a fixing member, and FIGS. FIG. 6 is a side view showing an example of a conventional general insulator type aerial terminal box, and FIG. 7 is a longitudinal sectional view of a conventional epoxy type T-branch aerial terminal section. DESCRIPTION OF SYMBOLS 1 ... Cable terminal, 2 ... Branch bushing, 2a ... Male base, 4 ... Conducting rod, 5 ... Insulator tube, 6 ... Receiving part, 7 ...
... conductor pull-out rod, 8 ... fixing member, 9 ... shield ring.

Claims (1)

(57) [Scope of request for utility model registration] 1. A resin-molded branch bushing into which a terminal of a cable for branch connection is inserted, and a male formed integrally with the branch bushing and extending in a direction perpendicular to the cable insertion direction. A porcelain having a shaped base, a conductive rod embedded in the branch bushing, electrically connected to the cable terminal, and protruding by a length connectable from the male base, and a receiving portion on which the male base is disposed. A branch bushing is directly fixed to the insulator pipe via fixing means, the insulator bush being made of an air-terminated insulator pipe, and a conductor extraction rod disposed in the insulator pipe and electrically connected to the conductive rod. A cable aerial termination.