JPS6332210B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for fixing a terminal connected to a movable contact for a vacuum valve of a vacuum shield breaker.

Generally, two conductors for each phase of a high-pressure part of a vacuum shield/breaker are led from the outside into the shield/breaker frame, and, for example, the conductor located at the top is directly connected to a fixed electrode of a vacuum valve. On the other hand, the conductor located at the bottom is connected to the movable electrode portion of the vacuum valve via the connecting terminal and the flexible conductor in this order.

By the way, a conventional fixing mechanism between a conductor and a connecting terminal connected to a movable electrode portion of the vacuum valve is as shown in FIG. That is, in FIG. 1, reference numeral 1 denotes an insulating member for supporting a conductor, which corresponds to, for example, a part of the frame of a vacuum shield or disconnector. A conductor 2 is fixed to the insulating member 1 by means of bolts and nuts which will be described later, and a main circuit disconnecting finger 3 is provided at its outer end. Reference numeral 4 denotes a connection terminal, which is connected via a flexible conductor 5 to a movable electrode of a vacuum valve (not shown). 6 is a bolt,
It is loosely fitted into a series of through holes 1a, 2a, and 4a formed in the insulating member 1, conductor 2, and terminal 4, and the spring washer 7 and nut 8 are sequentially fitted into the protruding portion on the side opposite to the head. In this way, the insulating member 1, the conductor 2, and the terminal 4 are integrally fixed between the head of the bolt 6 and the nut 8.

However, in the conventional configuration shown in FIG. 1, thermal expansion also occurs in the thickness direction each time the temperature rises due to the current flowing through the conductor 2 and the terminal 4.
This results in the insulating member 1 being strongly compressed. In the process of repeating such operations, the conductor supporting insulating member 1 contracts slightly, and this contracted state continues without change. Therefore, the bolt 6 and nut 8 are not sufficiently tightened, and the pressure force between the conductor 2 and the terminal 4 is weakened. This, of course, has the disadvantage that the resistance between the conductor 2 and the terminal 4 increases, which tends to impede the flow of current from the movable contact of the vacuum valve to the finger 3.

For this reason, for example, a method of fixing the conductor 2 and terminal 4 by embedding a metal insert in the insulating member 1 and forming a bolt-fitting tap therein is considered, but this is difficult to put into practical use due to the complicated structure. There's a problem.

An object of the present invention is to provide a structure in which a terminal and a conductor electrically connected to a movable contact of a vacuum valve are tightened and fixed to an insulating frame member using bolts and nuts. The purpose is to continuously maintain the press-contact state between the terminal and the conductor by fitting them together.

The illustrated embodiment will be specifically described below. FIG. 2 is a sectional view of a main part showing an embodiment of the present invention. In FIG. 2, 11 is a vacuum valve. Reference numeral 12 denotes a movable electrode portion connected to the movable contact of the vacuum valve 11. Reference numeral 13 denotes a frame which surrounds the entire vacuum chamber and disconnector including the vacuum valve 11. Reference numeral 14 denotes an insulating member for supporting a conductor, which is formed integrally with the frame. A conductor 15 is supported in a groove 14a formed in the insulating member 14, and a main circuit disconnection finger 16 is attached to its outer end. 17 is a bolt whose leg 17a is fitted into a U-shaped opening 14b formed in the insulating member 14;
In addition, the head 17b is located below the opening 14b. On the other hand, a screw 17c formed on the bolt leg 17a is fitted into a female screw 15a formed on the conductor 15. A connecting terminal 18 is connected to the movable electrode portion 12 of the vacuum valve 11 via a flexible conductor 19, and the bolt leg portion 17a is loosely fitted into a through hole 18a formed in the connecting terminal 18. 2
0 is a spring washer, and 21 is a nut, each of which is fitted in order into the portion of the bolt leg 17a that extends from the through hole 18a of the terminal 18. 22 is a bolt and conductor 1
5 and the connection terminal 18 from changing relative positions.

In the above configuration, when the vacuum valve 11 is in the closed state, the fixed electrode part of the vacuum valve 11 is electrically connected to the movable electrode part, and the flexible conductor 1
A current flows through terminal 18 and conductor 15 through terminal 9 .
Note that the connection between the conductor 15 and the insulating member 14 is as follows:
This is achieved by fitting the head 17b of the bolt 17, the thread 17c formed on the bolt leg 17a, and the female thread 15a formed on the conductor 15. On the other hand, the connection between the terminal 18 and the conductor 15 is achieved by the nut 21 and the fitting between the screw 17c and the female screw 15a.

Note that even if the positions of the head 17b of the bolt 17, the nut 21, and the spring washer 20 are reversed, the same operation and effect can be obtained. Further, the leg portion 17a of the bolt of the conductor 15 and the terminal 18
The portion that is loosely fitted in may be either a through hole or an opening, and is not limited to the embodiment.

As described above, the terminal fixing mechanism of the vacuum shield disconnector according to the present invention has a terminal connected to the movable electrode part of the vacuum valve by a flexible conductor, and a conductor that fixes the finger responsible for disconnecting the main circuit to the outer end. As a means of joining and fixing the two to the insulating member, the bolt is fitted into the head of the bolt and the leg of the bolt, centering on the fitting part between the screw formed on the leg of one bolt and the female thread formed on the conductor. The supporting insulating member and the terminal are loosely fitted between the bolt leg and the bolt leg. Based on this configuration, the vacuum valve movable electrode is always used because there is no room for the terminal and the conductor to be connected via an insulating member that undergoes stress and undergoes some permanent shrinkage without complicating the structure. It has a feature that the pressure contact force between the terminal connected to the part and the conductor fixing the finger can always be strongly maintained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional structure, and FIG. 2 is a sectional view showing a structure according to the present invention. DESCRIPTION OF SYMBOLS 12... Movable electrode part of a vacuum valve, 14... Insulating member for support, 14b... Opening, 15... Conductor, 15a...
Female thread formed on the conductor, 16...Finger, 17
...Bolt, 17c...Male thread, 18...Terminal, 18a
...Through hole, 19...Flexible conductor, 21...Nut.

Claims (1)

[Claims] 1. In a configuration in which a terminal connected to the movable electrode part of a vacuum valve via a flexible conductor and a conductor provided with a main circuit disconnection finger at the outer end are bonded and then fixed to a supporting insulating member, the fixing bolt A female thread is formed on the conductor to fit into the screw formed on the leg of the bolt, an opening into which the leg of the bolt loosely fits is formed on the insulating member and the terminal, and a female thread formed on the bolt and the conductor is formed. A vacuum shield with one of the opening of the terminal and the opening of the insulating member arranged between the fitting part and the bolt head and between the fitting part and the nut fitted into the bolt, respectively. Dexterity terminal fixing mechanism.