JP2002304937A - Vacuum valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To break high current even in a high voltage circuit by utilizing permanent magnets and appropriately rotating an arc in the peripheral direction of a contact to prevent the accumulation of the arc in the specific portion. SOLUTION: Permanent magnets 21a, 21b are arranged on the back side of a fixed side contact, 19 so as to locate a fixed side power supply shaft 15 between them, and permanent magnets 22a, 22b are arranged on the back side of a moving side contact 20, so as to locate a moving side power supply shaft 16 between them. Magnetic poles of the permanent magnets 21a, 21b, 22a, 22b are arranged so as to form N poles on the outer circumferential side and S poles on the center side, for example, so that the outside in the diameter direction of the fixed side contact 19 or the moving side contact 20 coincides with the center part side, and a magnetic flux along the diameter direction is generated between the contacts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum valve having improved shutoff performance.

[0002]

2. Description of the Related Art As three basic characteristics required for a vacuum valve, there are a breaking performance, a withstand voltage performance, and a welding resistance performance. Among these, as a means for improving the breaking performance, there is a means for rotating the arc in the circumferential direction of the electrode so that the arc generated between the electrodes (or the contacts) does not stay at a specific location at the time of breaking. Here, an example of an electrode structure for rotationally driving the arc will be described with reference to FIG. In the figure, one end of each of a pair of conducting shafts 1 and 2 provided in a vacuum vessel (not shown) is
Cup-shaped electrodes 3 and 4 having a concave cross section are provided. Contacts 5 and 6 having holes in the center are attached to the opening sides of the cup-shaped electrodes 3 and 4, and the closed side is attached to one end of the conducting shafts 1 and 2. On the other hand, a plurality of inclined slits 7 and 8 are equally arranged on the side surfaces of the cup-shaped electrodes 3 and 4 with the inclined directions being opposite to each other, and the positions of the slits 7 and 8 in each electrode are set in the circumferential direction. It is provided so as to be located alternately. Here, in the energized state, an external operating force is applied to one energized shaft, for example, energized shaft 2 and contacts 5, 6
Is opened, an arc 9 is generated between the contacts 5 and 6,
The generated arc 9 has a circumferential electromagnetic force due to the interaction between the magnetic flux generated by the current flowing between the slits 7 in the cup-shaped electrode 3 and between the slits 8 in the cup-shaped electrode 4 at substantially the same inclination as the slits 7 and the arc current, and the arc current. Works. As a result, since the arc 9 rotates in the circumferential direction between the contacts 5 and 6 and does not stay at a specific location, the high-temperature arc 9 does not stay at the contacts 5 and 6. Therefore, damage to the contacts 5 and 6 is suppressed, so that a large current can be cut off.

[0003]

However, in the above-described vacuum valve, when the distance between the contacts is increased for application to a high voltage circuit, the slit between the slits 7 in the cup-shaped electrode 3 and the slit in the cup-shaped electrode 4 are increased. The magnetic flux generated by the current flowing between the slits 8 at substantially the same inclination as the slits 7 and 8 is small because it is inversely proportional to the distance between the contacts, and the electromagnetic force for driving the arc 9 in the circumferential direction is small. For this reason, the arc 9 stagnates at a specific location, and the stagnation location of the arc 9 at the contacts 5 and 6 is greatly damaged, so that a large current cannot be cut off. On the other hand, as another means that can prevent stagnation of an arc at a specific location, a vacuum valve that generates a vertical magnetic field or a vertical magnetic field and a horizontal magnetic field is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 9-115398.
That is, the arc is dispersed by providing a coil electrode for generating a magnetic flux parallel to the arc between the main electrodes (contacts) to generate a vertical magnetic field. In this case, the magnetic flux distribution of the vertical magnetic field generated by the coil electrode between the main electrodes is
The distribution has a substantially sinusoidal shape that becomes maximum at the radial center portion between the main electrodes and becomes smaller toward the radially outer peripheral side. Then
Since the arc has the property of concentrating in the region of strong magnetic flux, the arc concentrates at the radial center between the main electrodes, and the radial center of the main electrode is greatly damaged, cutting off large currents. Can not be done.

Therefore, in the vacuum valve disclosed in Japanese Patent Application Laid-Open No. Hei 9-115398, in addition to the longitudinal magnetic field, the energizing shafts of the pair of energizing shafts are arranged such that the permanent magnets on the side facing the permanent magnets are the same. In the axial direction of the main electrode, thereby generating a transverse magnetic field in the central portion in the radial direction between the main electrodes in the direction perpendicular to the axial direction. By driving to the side, the concentration of the arc at the radial center portion between the main electrodes is prevented. However, such a vacuum valve can be applied to a high voltage circuit, but it is necessary to separately provide a coil electrode to generate a vertical magnetic field, and furthermore, a hole is formed in an energized shaft to accommodate a permanent magnet. Therefore, the structure becomes complicated. In addition, even if the arc at the center in the radial direction between the main electrodes is driven to the outer periphery in the radial direction, basically, a vertical magnetic field electrode at which the arc tends to concentrate at the center in the radial direction between the main electrodes is used. For this reason, it is difficult to obtain sufficient blocking performance. Further, in some cases, the arc protrudes outside from between the fixed contact and the movable contact, and the arc stagnates to a specific location, causing damage, and improvement in this respect is also required. A first object of the present invention is to provide a vacuum valve capable of improving the breaking performance by driving the arc to rotate in the circumferential direction of the contact with a simple structure even when applied to a high-voltage circuit. It is in.

A second object of the present invention is to rotate an arc protruding outward from between a fixed contact and a movable contact in a circumferential direction with a simple structure even when applied to a high voltage circuit. It is to provide a vacuum valve that can be driven.

[0006]

SUMMARY OF THE INVENTION In order to achieve the first object, the present invention provides a vacuum vessel, a fixed-side current-carrying shaft and a movable-side current-carrying shaft penetrating through the vacuum vessel, and a fixed-side current-carrying shaft. The fixed-side contact and the movable-side contact which are attached to one end of each of the movable-side energized shafts and which can be separated and contacted in the vacuum vessel, and the contact are attached to at least one of the fixed-side contact and the movable-side contact. And a permanent magnet for generating a magnetic flux for rotating an arc generated between the fixed contact and the movable contact in the circumferential direction of the contact when the arc is cut off. According to such a configuration, the permanent magnet provided on at least one of the fixed-side contact and the movable-side contact generates a magnetic flux between the contacts in the radial direction of the contact, which is generated at the time of interruption. The arc can be driven to rotate in the circumferential direction of the contact. In addition, the present invention that achieves the second object is, in addition to the above-described invention, a shield provided in a vacuum vessel so as to cover the periphery of the fixed contact and the movable contact, and provided on the outer peripheral side of the shield. And a permanent magnet for generating a magnetic flux so that an arc which protrudes outside from between the fixed side contact and the movable side contact at the time of interruption is rotated in the circumferential direction of the shield.

According to such a configuration, the magnetic flux generated by the permanent magnet disposed on the outer periphery of the shield provided so as to cover the periphery of the fixed side contact and the movable side contact causes the fixed side contact and the movable side contact to be formed. The arc protruding outside from between can be driven to rotate in the circumferential direction of the shield.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. (First Embodiment) FIG. 1 is a sectional view of a vacuum valve for explaining an embodiment of the present invention. In the figure, a vacuum vessel is formed by sealing both ends of a cylindrical insulating tube 10 with lids 11 and 12 and maintaining the inside at a high vacuum. Inside the vacuum vessel, a fixed-side electrode portion 13 and a movable-side electrode portion 14 are provided so as to be able to contact and separate from each other via respective contacts, and the fixed-side electrode portion 13 is attached to one end of a fixed-side energized shaft 15 and is movable. The side electrode portion 14 is attached to one end of the movable side conducting shaft 16. The movable-side energized shaft 16 is drawn out to the outside in a vacuum-tight manner so that it can be operated in the axial direction by a bellows 17 formed around the movable-side energized shaft 16. The fixed-side electrode portion 13 and the movable-side electrode 14 can be brought into contact with and separated from each other by a driving force from an operation mechanism (not shown) received at the other end of the movable-side energized shaft 16, and provided with a vacuum valve and an operation mechanism. Open and close the current flowing through the circuit. On the other hand, a shield 18 formed so as to cover the outer periphery of the fixed-side electrode portion 13 and the movable-side electrode portion 14 is attached to the insulating cylinder 10, and, for example, dust floating in the vacuum vessel or the like is formed on the inner surface of the insulating cylinder 10. Prevents sticking.

Here, of the above-described vacuum valve configuration, the fixed side electrode portion 13 and the movable side electrode portion 14 are:
This will be described with reference to FIG. Note that the same components as those in FIG. 1 are denoted by the same reference numerals. In the same figure, the disc-shaped fixed contact 19 in the fixed electrode 13 and the disc-shaped movable contact 20 in the movable electrode 14 are in an open state, and the movable contact of the fixed contact 19 is movable. A plurality of permanent magnets 21a and 21b each forming a rectangular parallelepiped as a magnetic flux generating means are provided on a surface (hereinafter, referred to as a back surface) opposite to a surface facing the contact 20 so as to sandwich the fixed-side energizing shaft 15 and extend in the radial direction. It is provided in such a manner. Furthermore, each permanent magnet 21a, 2
1b is arranged such that the magnetic pole located on the radially outer peripheral side of the fixed side contact 19 and the magnetic pole located on the central part side respectively match, for example, such that the outer peripheral side is an N pole and the central part is an S pole. . Similarly, a plurality of permanent magnets 22a and 22b each forming a rectangular parallelepiped are provided on a surface of the movable contact 20 opposite to the surface facing the fixed contact 19 (hereinafter referred to as a back surface).
Are provided so as to sandwich the movable-side energized shaft 16 and extend in the radial direction, respectively. Furthermore, each permanent magnet 22
a and 22b are arranged such that the magnetic pole located on the outer peripheral side in the radial direction of the movable side contact 20 and the magnetic pole located on the central part side respectively match, for example, such that the outer peripheral side is an N pole and the central part is an S pole. Is done.

In such a configuration, the permanent magnet 21a
21b and 22a and 22b repel each other at the center in the radial direction, and repel each other between the contacts 19 and 20, so that the permanent magnets 21a and 21b fix the fixed contact 19 and the movable contact 20 between them. Magnetic fluxes 23 a and 23 b are generated along the radial direction of the side contact 19, and the permanent magnets 22 a and 22 b
b, the magnetic flux 24a along the radial direction of the movable contact 20;
24b occurs. These magnetic fluxes 23a, 23b, 24
a and 24b are orthogonal to the arc 25 generated between the fixed contact 19 and the movable contact 20. Thus, the arc 25 and the magnetic fluxes 23a, 23b, 24a,
When the angle 24b is orthogonal, the magnetic flux density B of the magnetic fluxes 23a, 23b, 24a, 24b orthogonal to the current I flowing through the arc 25
As a result, an electromagnetic force proportional to B × I is applied to the arc 25 in FIG.
Of the fixed side contact 19 and the movable side contact 20 in the circumferential direction around the conducting shafts 15 and 16 of the fixed side contact 19 and the movable side contact 20. Is driven to rotate in the circumferential direction. As described above, according to the present embodiment, the arc 25 rotates between the fixed contact 19 and the movable contact 20 in the circumferential direction of the contact with a simple structure in which the permanent magnet is provided on the back surface of the contact. This prevents the arc 25 from stagnating at a specific point of the contact. Therefore, damage to the fixed side contact 19 and the movable side contact 20 is reduced, and a large current can be cut off. Moreover, even if the opening distance between the contacts is increased, the generation of magnetic flux by the permanent magnet is not impaired, so that application to a high-voltage circuit is also possible.

The permanent magnet 2 on the back of the fixed contact 19
Since the magnetic poles 1a and 21b and the magnetic poles of the permanent magnets 22a and 22b on the back of the movable contact 20 have the same polarity opposite to each other via the fixed contact 19 and the movable contact 20, they repel each other. The repulsive force acts on the fixed contact 19 and the movable contact 20 as a force in the opening direction. For this reason, the opening force of the fixed side contact 19 and the movable side contact 20 increases, and the opening speed increases, which also improves the large current interruption performance. In FIG. 2, the magnetic poles of the permanent magnets 21 a, 21 b, 22 a, and 22 b are N-pole on the radially outer side of the fixed-side contact 19 and the movable-side contact 20, and S-pole on the center side. Similar effects can be obtained by arranging the S pole on the side and the N pole on the center side. On the other hand, in FIG. 2, a permanent magnet 21a is provided on the back surface of each of the fixed contact 19 and the movable contact 20.
Although 21b, 22a, and 22b are arranged, a configuration in which the permanent magnets 21a and 21b are arranged only on one of them, for example, only on the back surface of the fixed contact 19 as shown in FIG. That is, the current I flowing through the arc 25 and the permanent magnet 2
Since the magnetic flux densities B of the magnetic fluxes 23a and 23b due to the magnetic fluxes 1a and 21b are orthogonal to each other, an electromagnetic force proportional to B × I is applied to the arc 25 in the vertical direction on the paper of FIG.
Acting in the circumferential direction between the fixed contact 9 and the movable contact 20, the arc 25 rotates in the circumferential direction between the fixed contact 19 and the movable contact 20 by this electromagnetic force. For this reason, the arc 25 does not stay at a specific portion of the contact, so that the fixed contact 19 and the movable contact 20 are less damaged, and a large current can be cut off.

Further, when the fixed contact 19 and the movable contact 20 are closed (closed), permanent magnets 21a,
In this case, the driving force to the movable-side energized shaft 16 may be small, since the repulsive force by 21b does not act.
Therefore, the operating mechanism for supplying the driving force may be small, which is advantageous for miniaturizing the vacuum circuit breaker.
Further, as shown in FIG.
1a and 21b, the movable contact 20 and the permanent magnet 22a,
For example, copper plates 26 and 27 may be arranged between 22b. According to such a configuration, the function of the contacts in the fixed side contact 19 and the movable side contact 20 is effective in maintaining good conduction characteristics. Further, when the magnetic flux of the permanent magnet penetrates, an eddy current is generated, and there is a concern that the magnetic flux due to the eddy current acts in a direction to cancel the magnetic flux generated by the permanent magnets 21a, 21b, 22a, 22b. It is not preferable to provide a slit for dividing the fixed contact 19 and the movable contact 20 in the circumferential direction in rotating the arc in the circumferential direction. Therefore, it is preferable to provide a slit for dividing the copper plates 26 and 27 in the circumferential direction. Thus, the generation of the eddy current may be suppressed. Also, as shown in FIG.
Instead of the fixed-side energizing shaft 15 and the movable-side energizing shaft 16, a fixed-side penetrating energizing shaft 15 a and a movable-side energizing energizing shaft 16 a penetrating a permanent magnet are provided.
The fixed-side contact 19 may be attached to one end of a through the permanent magnets 21a and 21b, and the movable-side contact 20 may be attached to one end of the movable through-current-carrying shaft 16a by penetrating the permanent magnets 22a and 22b.

In such a configuration, due to the structure of the electrode portion, in the above-described embodiment, the current path of the fixed-side conducting shaft 15, the fixed-side contact 19, the arc 25, the movable-side contact 20, and the movable-side conducting shaft 16 is long. Therefore, the force acting on the arc 25 increases, and the probability that the arc 25 protrudes from the outer peripheral portions of the fixed side contact 19 and the movable side contact 20 increases, thereby adversely affecting the breaking performance. 25
Therefore, the probability that the arc 25 protrudes outside from between the fixed contact 19 and the movable contact 20 can be reduced. (Second Embodiment) FIG. 6 is an enlarged sectional view showing a second embodiment of the present invention, in which the fixed side electrode portion 13 and the movable side shown in FIG. 4 in the first embodiment are shown. Instead of the electrode section 14, at least one of the fixed-side energized shaft 15 side and the movable-side energized shaft 16 side is provided with a hole extending from the contact point to the energized shaft. In this embodiment, the hole 28 extending from the fixed contact 19 to the fixed energizing shaft 15 and the hole 29 extending from the movable contact 20 to the movable energizing shaft 16 are provided. Or just According to such a configuration, in addition to the effects of the above-described first embodiment, the following effects are also achieved.

That is, if the arc 25 is fixed to the fixed contact 1
Assuming that the ignition occurs near the center of the fixed-side energizing shaft 15 and the movable-side energizing shaft 16 at the radial center portion between the contact 9 and the movable-side contact 20, the first embodiment described above. In the configuration shown in FIG. 4, the permanent magnets 21a, 21b, 22a, 22
Since the magnetic fluxes 23a, 23b, 24a, and 24b due to b hardly interlink with the arc 25, the arc cannot be driven to rotate in the circumferential direction of the contact. There is a possibility that damage to the side contact 20 may increase. According to the present embodiment, holes 28 and 2
By providing 9, the distance between the fixed-side energized shaft 15 and the movable-side energized shaft 16 in the vicinity of the center of the axis becomes longer, so that it is possible to prevent the arc 25 from being ignited in this vicinity. Therefore, the arc 25 is composed of the fixed contact 19 and the movable contact 20.
And the permanent magnets 21a, 21b, 22a, 22
The magnetic fluxes 23a, 23b, 24a, and 24b are generated at positions where they sufficiently act, and the arc 25 can be reliably driven to rotate in the circumferential direction of the contact. Also, as shown in FIG. 7, the fixed contacts 1 are inserted into the holes 28 and 29 shown in FIG.
9 and the same material as the contact material of the movable contact 20, for example, a material 30, 3 containing CuCr as a main component which hardly emits metal vapor
1, the fixed contact 19 and the movable contact 2
When the arc 25 is ignited near the center in the radial direction of 0, the generation of metal vapor can be suppressed, which is advantageous in preventing a decrease in withstand voltage performance.

(Third Embodiment) FIG. 8 is an enlarged sectional view showing a third embodiment of the present invention. In the figure, the fixed side contact 19 and the movable side contact 20 are in an opened state, and permanent magnets 32 a and 32 b are provided on the back surface of the fixed side contact 19 as magnetic flux generating means so as to sandwich the fixed side conducting shaft 15. . The permanent magnets 32a and 32b are arranged such that the magnetic poles are arranged along the axial direction of the fixed-side energizing shaft 15, and the magnetic poles located on the movable contact 20 side and the magnetic poles located on the opposite contact side (the lid 11 side in FIG. 1). Are arranged so that, for example, the contact side is an N pole and the opposite contact side is an S pole. Similarly, permanent magnets 33 a and 33 b are provided on the back surface of the movable contact 20 so as to sandwich the movable conduction shaft 16. The permanent magnets 33a and 33b are arranged such that the magnetic poles are arranged along the axial direction of the movable-side energized shaft 16, and the magnetic poles located on the fixed-side contact 19 side and the counter-contact side (lid 1 in FIG. 1).
2) so that the magnetic poles located on
For example, they are arranged such that the contact side has an N pole and the opposite contact side has an S pole. In such a configuration, the permanent magnets 32a and 32b generate magnetic fluxes 34a and 34b along the radial direction of the fixed contact 19 between the fixed contact 19 and the movable contact 20, and the permanent magnets 33a and 33b generate the magnetic flux 34a and 34b. Movable contact 20
The magnetic fluxes 35a and 35b are generated along the radial direction of.

The magnetic fluxes 34a, 34b, 35a, 35b are:
The magnetic fluxes 34a, 34b, 35a, and 35 are orthogonal to the arc 25 generated between the fixed contact 19 and the movable contact 20, and are orthogonal to the current I flowing through the arc 25.
Due to the magnetic flux density B of b, an electromagnetic force proportional to B × I acts on the arc 25 in the vertical direction on the paper of FIG. 8, in other words, in the circumferential direction of the fixed contact 19 and the movable contact 20, and the arc 25 With this electromagnetic force, the portion between the fixed contact 19 and the movable contact 20 is driven to rotate in the circumferential direction. Even if it is configured as in the present embodiment, the arc 25 stagnates at a specific position of the contact by rotating the arc 25 between the fixed contact 19 and the movable contact 20 with a simple structure. Disappears. Therefore, damage to the fixed side contact 19 and the movable side contact 20 is reduced, and a large current can be cut off. (Fourth Embodiment) FIG. 9 is an enlarged sectional view for explaining a fourth embodiment of the present invention. In the figure,
For example, a fixed-side electrode portion 13 and a movable-side electrode portion 14 as shown in FIG. 3 are provided, and a fixed-side contact 19 provided at one end of a fixed-side energized shaft 15 and a movable-side contact provided at one end of a movable-side energized shaft 16. A shield 18 formed so as to cover the periphery of 20
A plurality of permanent magnets 36
a and 36b are provided. Further, the permanent magnets 36a, 36
The magnetic pole b is arranged such that the fixed-side contact 19 and the movable-side contact 20 respectively correspond to each other.
The N side is the N pole, and the movable contact 20 side is the S pole.

In such a configuration, the magnetic fluxes 37, 38 from the permanent magnets 36a, 36b are provided inside the shield 18.
Is formed. Here, for example, if the arc 25 protrudes toward the shield 18 from between the fixed contact 19 and the movable contact 20, the arc 25 stagnates in a specific portion of the shield 18 in the past, causing damage such as opening a hole. In this embodiment, the electromagnetic force proportional to B × I is applied to the arc 25 by the magnetic flux density B of the component 37 perpendicular to the current I flowing through the arc 25 in FIG. It acts as a force along the vertical direction on the paper, in other words, the circumferential direction of the inner surface of the shield 18. For this reason, the arc 25
This electromagnetic force drives the inner surface of the shield 18 to rotate in the circumferential direction. According to the present embodiment, arc 25 is shield 1
Since the inner surface of the shield 8 is driven to rotate in the circumferential direction, the arc 25 does not stay at a specific position of the shield 18. Therefore, in addition to the effects of the permanent magnets 21a and 21b, damage to the fixed contact 19, the movable contact 20, and the shield 18 is reduced, so that a large current can be cut off. In FIG. 9, one permanent magnet is arranged on the outer periphery of the shield 18. However, as shown in FIG.
8, permanent magnets 39a and 39b and permanent magnets 39c and 3
For example, two permanent magnets such as 9d may be arranged. However, in this case, it is necessary to match the directions of the magnetic poles of the adjacent permanent magnets. For example, in FIG. 10, the opposite side is an S pole and the opposite side is an N pole.

Even in this case, for example, when the arc 25 protrudes from the fixed contact 19 and the movable contact 20 toward the shield 18, the arc 25 can be driven to rotate in the circumferential direction on the inner surface of the shield 18. The arc 25 includes the fixed contact 19 and the movable contact 20 and the shield 18.
Stagnation at a specific location. Therefore, the fixed side contact 19, the movable side contact 20, and the shield 18 are less damaged, so that a large current can be cut off.
On the other hand, in the configuration shown in FIGS.
Usually, Cu is often used as the material, but using a material mainly composed of CuCr suitable for breaking a large current is more advantageous in improving the breaking performance. More specifically, for example, when the arc 25 reaches the shield 18, the shield 18 becomes substantially an intermediate electrode, and the arc 25 passes from the fixed contact 19 through the shield 18 to the movable contact 2.
Since it is formed at 0, a cathode spot and an anode spot are formed on the shield 18, which is the same as the state where the fixed contact 19 and the movable contact 20 are exposed to the arc 25. For this reason, as a material of the shield 18, for example, a material mainly composed of CuCr for interrupting a large current is used, and the thickness of the intermediate portion of the shield 18 to which the arc 25 is attached is adjusted to the fixed contact 1.
9 and the movable contact 20, the distance between the fixed contact 19 and the shield 18 and between the shield 18 and the movable contact 2
An arc 25 can be generated between 0 and current can be interrupted at two gaps, leading to an improvement in interrupting performance. At this time, it is more effective if the contact material of the fixed contact 19 and the movable contact 20 is CuCr.

[0019]

As described in detail above, according to the present invention,
Even when applied to high voltage circuits, it has a simple structure,
Since the arc generated when the electrode is opened at the time of energization is reliably driven to rotate in the circumferential direction and the stagnation of the arc at a specific location can be prevented, the breaking performance can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a vacuum valve for describing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of the fixed-side electrode unit and the movable-side electrode unit of FIG. 1 showing the first embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing a modification of FIG. 2;

FIG. 4 is an enlarged sectional view showing another modification of FIG. 2;

FIG. 5 is an enlarged sectional view showing still another modification of FIG. 2;

FIG. 6 is an enlarged sectional view showing a second embodiment of the present invention.

FIG. 7 is an enlarged sectional view showing a modification of FIG. 6;

FIG. 8 is an enlarged sectional view showing a third embodiment of the present invention.

FIG. 9 is an enlarged sectional view showing a fourth embodiment of the present invention.

FIG. 10 is an enlarged sectional view showing a modification of FIG. 9;

FIG. 11 is an enlarged cross-sectional view for explaining a cup-shaped electrode in a conventional vacuum valve electrode structure.

[Explanation of symbols]

13: fixed-side electrode unit, 14: movable-side electrode unit, 18, 18
a, 18b: shield 19: fixed contact, 20: movable contact, 21a, 21
b, 22a, 22b, 32a, 32b, 33a, 33
b, 36a, 36b, 39a, 39b, 39c, 39
d, 44a, 44b, 44c, 44d ... permanent magnet

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Yoshimitsu Niwa 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu Office (72) Inventor Hiroshi 1 Toshiba-cho, Fuchu-shi Tokyo F term (reference) 5G026 CB02 DA10 HB05 5G027 AA03 BA02 BB03

Claims (6)

[Claims] A vacuum vessel, a fixed-side energized shaft and a movable-side energized shaft penetrating the vacuum vessel, and one end of each of the fixed-side energized shaft and the movable-side energized shaft; A fixed-side contact and a movable-side contact that can be separated and contacted within, and at least one of the fixed-side contact and the movable-side contact are provided so as to sandwich an energized shaft to which the contact is attached, and the fixed at the time of cutoff A vacuum valve having a permanent magnet for generating a magnetic flux for rotating an arc generated between the side contact and the movable side contact in a circumferential direction of the contact. 2. The permanent magnet according to claim 1, wherein a plurality of the permanent magnets are provided so as to sandwich the current-carrying shaft and the magnetic poles are located along a radial direction of the contact. 2. The vacuum valve according to claim 1, wherein the magnetic poles are arranged so as to coincide with the magnetic poles at the center in the radial direction. 3. A plurality of permanent magnets are provided so as to sandwich the energized shaft and to have magnetic poles located along the axial direction of the energized shaft, and the magnetic poles on the contact side of each of the permanent magnets and the anti-contact are provided. 2. The vacuum valve according to claim 1, wherein the magnetic poles on the side are arranged so as to coincide with each other. 4. The device according to claim 1, wherein at least one of the fixed-side energized shaft side and the movable-side energized shaft side is provided with a hole extending from a contact point to the energized shaft. Vacuum valve. 5. The vacuum valve according to claim 4, wherein a material similar to a contact material of the contact is coated on an inner surface of the hole. 6. A shield provided in the vacuum vessel so as to cover the periphery of the fixed-side contact and the movable-side contact, and a shield provided on an outer peripheral side of the shield, wherein the shield is provided when the fixed-side contact and the movable-side contact are cut off. The vacuum valve according to any one of claims 1 to 5, further comprising: a permanent magnet that generates a magnetic flux so as to rotationally drive an arc that protrudes outward from the space in a circumferential direction of the shield.