JPS593832A - Vacuum interrupter - 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 The present invention relates to a vacuum interrupter, and more particularly to a vacuum interrupter that is integrally equipped with a coil electrode that generates a magnetic field parallel to an arc when interrupted.

This type of vacuum interrogator 1f'i is generally constructed as shown in FIG. That is, glass is a cylinder 11 made of an insulating material such as ceramics. The cylinder 11 is provided with end plates 12 and 13 made of metal that close both ends of the cylinder 11 and a bellows 14 to form a vacuum container 10 whose interior is kept under a high vacuum, and further penetrated through one end plate 12 in an airtight manner. It is configured to include a circuit conductor 2 and another circuit conductor 3 which is provided airtightly penetrating the other end plate 13 via a bellows 14 and is movable up and down in the figure.

The circuit conductors 2 and 3 are lead rods 21 and 31, respectively.
and electrodes 20 and 30 provided at the inner end of each lead rod. Further, these electrodes 20 and 30 are provided with a nose cap contact portion 22a, 32a, and a lead rod 21.
and arc electrodes 22 and 32 provided at the inner ends of 31 via high-resistance spacers (not shown) made of a material with low conductivity.
The current flowing through the lead rods 21 and 31, which are located at the backs of these arc electrodes 22 and 32 (on the side opposite to the contact portion), is changed to a roof current centered on the lead rods 21 and 31, respectively. It is constructed with a coil (M23 and 33) that generates a magnetic field parallel to the arc (axial direction - magnetic field in the 1 upper F direction in FIG. 1).

In addition, in FIG. 1, 15 is the main metal shield body,
The metal vapor generated from the arc electrodes 2 and 3 at the time of interruption is captured to prevent the inner wall surface of the cylinder 11 made of an insulating material from being contaminated.

By the way, in the vacuum interrupter l as described above, the arc heavy bodies 22 and 3 included in the circuit conductors 2 and 3
2 is usually made of a highly conductive material such as Ctb; in this case, the arc electrode 22.
There is a problem in that eddy currents are generated in the coils 4M23 and 33, and the magnetic flux density of the magnetic field parallel to the arc (axial magnetic field) generated by the coil turtles 4M23 and 33 is reduced.

To address this problem, a plurality of radially located slits 3 are usually provided in the arc electrode 32, as shown in FIG.
2b is provided. Although not shown, a similar slit is also provided in the other arc electrode 22.

However, although it is possible to prevent the generation of eddy current by providing a plurality of slits in each arc electrode, the provision of the slits causes a large number of edges to be formed on the surface of the arc electrode. Since each edge part of each arc electrode directly faces the other electrode through a vacuum space during opening (cutting), the electric field tends to concentrate, causing re-ignition and reducing withstand voltage. is new.

Also, on the outer periphery of the arc electrode and coil electrode.

There is an edge part formed by the slit 32 and the notch 33a for forming the coil, and this is the main metal shield body 1.
5, the electric field was concentrated in this area and the withstand voltage was lowered.

The present invention has been made in view of the above points, and includes providing an auxiliary metal shield body that individually surrounds a pair of electrodes,
It is an object of the present invention to provide a vacuum interrogator in which a pair of electrodes are respectively immersed into an auxiliary metal shield body at the time of shutoff, thereby improving the withstand voltage.

Next, one embodiment of the present invention will be explained based on FIG.
In these figures, the same reference numerals as those in FIGS. 1 and 2 described above indicate equivalent products, and detailed explanations thereof will be omitted.

That is, reference numerals 45 and 4b are thin, approximately cup-shaped auxiliary dust shield bodies, each of which has a ring-shaped contact 41 at its opening. These auxiliary metal shields 4α, 4b and the contact 41 are made of a material with low conductivity, such as stainless steel.

It consists of inoconel or beryllium.

One auxiliary metal shield 4α is located on the upper side in the figure and is installed on the circuit conductor 2, which is the fixed side, with its contact 41 facing downward, and the contact portion 22
G, electrode 2 consisting of arc electrode 22 and coil electrode 23;
0 and the coil electrode 2 via the elastic fitting 42.
It is fixed to the back (upper side in the figure) of 3.

The elastic fitting 42 is formed into a bellows or a coil spring, and is made of a material such as stainless steel or Inconel whose elastic force does not decrease due to brazing temperature or heating exhaust temperature. Also, as in the state shown in Figure 3 (when shut off),
When the auxiliary metal shield body 4G is in a free state without any upward force acting on it, the tip (lower end) of the contactor 41
is configured to protrude downward from the central contact portion 22a of the electrode 20. Furthermore, the auxiliary metal shield 4G is not limited to being fixed to the back of the coil electrode 23 via the elastic fitting 42, but may also be fixed to the lead rod 21.

The other auxiliary metal shield 4b is located on the lower side in the figure and is provided on the circuit conductor 3, which is the movable side, with the contact 41 provided on the upper side, and the contact part 32α, the arc electrode 32, and the coil A contact 41 surrounding the electrode 30 consisting of W4 poles 33 is fixed to the lead rod 31 and protrudes upward from the contact 'VA32α at the center of the electrode 30.

In addition, this auxiliary metal shield body 4661! J-do rod 31
Not only can it be installed fixedly, but it can also be installed via an elastic fitting, or it can be installed with a coil. There is no problem even if it is fixed to the back of the electrode 33.In the vacuum interrogator IK having the configuration as explained above, when the VC is in the state shown in FIG. Arc′ electrode 22
．． 32 is recessed into each of the auxiliary metal shields 4cL and 46, and these auxiliary metal shields 4a and 4b directly span the circuit conductors 2 and 3, so that when the circuit is cut off (opened) The pair of auxiliary metal shield bodies 4a and 4h bear the burden of the withstand voltage during extreme conditions.

On the other hand, at the time of closing (at the time of closing), when the circuit conductor 3 moves upward, the auxiliary metal shield 4b provided on this circuit conductor 3
However, the other (upper) auxiliary metal shield body 4G is pushed up to form a pair of contact portions 22a.

32g comes into contact with it.

Note that since the auxiliary metal shields 4α and 46 are made of a material with low conductivity and are thin and thick, almost no current flows therethrough, and the problem of arcing does not occur.

As is clear from the above description, the vacuum interrupter of the present invention can achieve various effects as described below. 4゜(1) Auxiliary metal shields 4m and 44 were provided to surround the electrodes 20 and 30 forming a pair of circuit conductors 2 and 3 that can be freely connected and separated, and to have the same potential as each of these circuit conductors 2 and 3. Therefore, the withstand voltage between each circuit conductor 2.3 and the main metal shield body 15 is improved, and the vacuum interrupter 1 can be made smaller (reduced in diameter).

(2) At least one of the auxiliary metal shields 4α or 4b of the pair of auxiliary metal shields 4 (L, 46) is provided so as to be movable in the axial direction, so that the pair of opposing electrodes 20 and 4b are movable in the axial direction. 30 yen each can be immersed in the auxiliary metal shield bodies 4α and 4b.

(3) Due to this, the auxiliary metal shields 4a and 4b made of a low-conductivity material with a small dimension between the opposing sides 1iItf bear the withstand voltage at the time of interruption.As in the conventional case, the arc electrode 22.32 bears the burden. The withstand voltage can be significantly improved compared to those with

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional vacuum interrupter, FIG. 2 is a perspective view of the electrode portion, and FIG. 3 is a cross-sectional view of a vacuum interrupter according to an embodiment of the present invention. 11 is a vacuum ink cleaner;
10 is a vacuum container, 2゜3e is a circuit conductor, 20.30 is an electrode, 21.31 is a keeled rod, 22.32 is an arc electrode,
23. 33 is a coil electrode, 4α, 46 is an auxiliary metal shield, 41 is a contact, and 42 is an elastic fitting. Figure 2 WJ 3 Ward

Claims (8)

[Claims] (1) A vacuum container comprising an insulator is provided with a pair of circuit conductors that can be connected and separated by passing through the vacuum container in an airtight manner, each circuit conductor consisting of a lead rod and an electrode provided at its inner end, and In a vacuum interrupter, the electrode is composed of an arc electrode provided with a half-umbrella contact portion, and a coil electrode located at the back of the arc electrode for generating a magnetic field parallel to the arc, in which each of the pair of electrodes is Auxiliary metal shields that individually surround each of the circuit conductors are fixedly provided so that the pair of auxiliary metal shields can come into contact with each other, and at least one of the auxiliary metal shields is provided via an elastic fitting. ,
A vacuum interrupter characterized in that each electrode is immersed in each auxiliary metal shield body when the contact is opened. (2) The vacuum interrupter according to claim 1, characterized in that an auxiliary metal shield is fixedly provided on the back of the coil electrode. (3) The vacuum ink converter according to claim 1, wherein the auxiliary shield body is fixed to the lead rod. (4) The vacuum interrupter as set forth in claim 1, 2, or 3, wherein the auxiliary metal shield body is made of a metal having low conductivity. (5) The auxiliary shield body is provided with a ring-shaped contact at the part that contacts the mating auxiliary metal shield body, or the N-circle paragraph 1 or 2 or 3 of the patent claim. The vacuum interrupter according to item 4. (6) The vacuum interrupter according to claim 5, wherein the contact included in the auxiliary metal shield body is made of a material with low conductivity. (7) The vacuum interaffeter according to any one of claims 1 to 6, wherein the elastic fitting is a coil spring. (8) The vacuum interrupter 1 according to any one of claims 1 to 6, wherein the elastic fitting is a bellows;