JP6958254B2 - Vacuum valve contacts and vacuum valves - Google Patents

Description

The present invention relates to a vacuum valve contact and a vacuum valve.

A vacuum circuit breaker is a device placed in the power receiving and distribution system, and plays a role of disconnecting a specific part from the power system. In particular, when an accident current occurs, it is responsible for cutting off the current and protecting the power system.
A vacuum valve is provided in the vacuum vessel of the vacuum circuit breaker to energize a current at normal times and shut off the current when an accident current occurs by connecting and disconnecting a pair of contacts.

The vacuum valve has a fixed side contact, a movable side contact, and a bellows that movably supports the movable side energizing shaft connected to the movable side contact and secures the airtightness inside the vacuum container. I have.
The fixed-side contact and the movable-side contact include a cup-shaped electrode and a disk-shaped contact plate that closes the opening of the electrode. Then, a plurality of slits that are inclined in the axial direction are provided in the cylindrical portion of the cup-shaped electrode, and a magnetic field in the electrode axial direction (hereinafter referred to as a longitudinal magnetic field) is applied between the contact plates of the fixed side contact and the movable side contact. Therefore, a longitudinal magnetic field method is adopted to improve the current cutoff performance.

The device of Patent Document 1 is known as a vacuum valve provided with a contact point for a longitudinal magnetic field type vacuum valve. In the vacuum valve of Patent Document 1, the arc generated when the current is cut off is diffused by the longitudinal magnetic field, so that the heat of the contact surface located at the electrode end is diffused, so that the metal vapor forming the arc can be supplied. Achieve limited current interruption.

Japanese Patent No. 6138601

By the way, in the vacuum valve of Patent Document 1 described above, metal vapor generated when a current is cut off, other plasma particles, and an arc spot generated between a pair of contact portions diffuse from the center of the contact plate to the outer peripheral end portion of the contact plate. After that, it moves from the cylindrical portion of the electrode to the fixed side electrode and the movable side current-carrying shaft.
If the arc spot moved to the movable electrode shaft moves to the bellows, the bellows may be damaged and the airtightness inside the vacuum vessel may be impaired.
Therefore, an object of the present invention is to provide a vacuum valve contact and a vacuum valve that eliminate the arc spot generated in the contact plate at an early stage and do not have a thermal effect on the airtight member of the vacuum valve.

In order to achieve the above object, the contact for a vacuum valve according to one aspect of the present invention includes an electrode having a cylindrical portion and a disk-shaped contact plate that closes an opening on one end side of the cylindrical portion, and is cylindrical. A plurality of electrode slits that are inclined in the axial direction are formed on the peripheral surface of the portion so as to be separated from each other in the circumferential direction, and an annular contact groove is formed on the outer peripheral side of the contact surface of the contact plate. ..
Further, the vacuum valve according to one aspect of the present invention is a device in which the above-mentioned vacuum valve contacts are mounted as a pair of contact parts that can be brought into contact with each other in a vacuum container.

According to the vacuum valve contact and the vacuum valve according to the present invention, it is possible to eliminate the arc spot generated at the contact portion by the time it moves to the airtight member of the vacuum valve and prevent the thermal influence on the airtight member. can.

It is sectional drawing which shows the internal structure of the vacuum valve of 1st Embodiment which concerns on this invention. It is a perspective view which shows the structure of the electrode which constitutes the movable side contact part of 1st Embodiment which concerns on this invention. It is a figure which showed the movable side contact part of 1st Embodiment which concerns on this invention in plan view. It is a perspective view which shows the movable side contact part of the 2nd Embodiment which concerns on this invention. It is sectional drawing which shows the movable side contact part of the 2nd Embodiment which concerns on this invention. It is a figure which shows the cross-sectional shape of the contact slit formed in the contact plate which constitutes the movable side contact part of the 2nd Embodiment which concerns on this invention, and FIG. FIG. 6B is a diagram showing a state in which an arc spot flows into the contact slit and the arc is in contact with the groove opening edge. It is a figure which shows the cross-sectional shape of the contact slit which is the 1st modification of the 2nd Embodiment which concerns on this invention, FIG. 7A is a state just before the arc spot flows into a contact slit, FIG. 7B is. It is a figure which shows the state which the arc spot flows into the contact slit, and the arc is in contact with the groove opening edge part. It is a figure which shows the cross-sectional shape of the contact slit which is the 2nd modification of the 2nd Embodiment which concerns on this invention, FIG. It is a figure which shows the state which the arc spot flows into the contact slit, and the arc is in contact with the groove opening edge part. It is sectional drawing which shows the internal structure of the vacuum valve of the 3rd Embodiment which concerns on this invention. It is a perspective view which shows the movable side contact part, the movable side energizing shaft and bellows of the 3rd Embodiment which concerns on this invention.

Next, the first to third embodiments of the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the plane dimensions, the ratio of the thickness of each layer, etc. are different from the actual ones. Therefore, the specific thickness and dimensions should be determined in consideration of the following explanation. In addition, it goes without saying that the drawings include parts having different dimensional relationships and ratios from each other.
Further, the first to third embodiments shown below exemplify devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is based on the material of the component parts. The shape, structure, arrangement, etc. are not specified as follows. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

[First Embodiment]
FIG. 1 shows an outline of the vacuum valve 1 of the first embodiment.
In the vacuum valve 1, a fixed-side sealing metal fitting 3 is sealed to one end of a cylindrical vacuum insulating container 2, and a movable-side sealing metal fitting 4 is sealed to the other end. The fixed-side energizing shaft 5 penetrates and is fixed to the fixed-side sealing metal fitting 3, and the fixed-side contact portion 6 is provided at the end of the fixed-side energizing shaft 5 in the vacuum insulating container 2.
Further, the movable side contact portion 7 which faces the fixed side contact portion 6 and is freely contactable and detachable is provided at the end of the movable side energizing shaft 8 which movably penetrates the movable side sealing metal fitting 4.

Further, the movable side contact portion 7 is provided with a bellows 9 which is connected to the movable side sealing metal fitting 4 to movably support the movable side energizing shaft 8 and secure the airtightness of the vacuum insulating container 2.
The movable side contact portion 7 is a cup-shaped electrode 10 fixed to the end of the movable side energizing shaft 8 in the vacuum insulating container 2 and a disk-shaped contact plate fixed by closing the opening of the electrode 10. 11 and.

As shown in FIG. 2, the electrode 10 is a member provided with a cylindrical portion 12 and a bottom portion 13 formed at one end of the cylindrical portion 12 in the axial direction.
A plurality of electrode slits 14 that cross diagonally with respect to the axial direction are formed in the cylindrical portion 12 of the electrode 10 at predetermined intervals in the circumferential direction.
As shown in FIG. 3, the contact plate 11 of the movable side contact portion 7 is formed with two curved inner contact slits 15 and two outer contact slits 16 at positions surrounding the central portion.

The inner contact slit 15 and the outer contact slit 16 coincide with the radial center P provided in the central portion of the contact plate 11, and the outer contact slit 16 is formed with a longer radius than the inner contact slit 15.
The two inner contact slits 15 are formed at positions symmetrical with respect to the center of radius P. Further, the two outer contact slits 16 are formed at positions rotated 90 degrees with respect to the inner contact slits 15 and at positions that are point-symmetrical with respect to the center of radius P.

Further, both ends of the inner contact slit 15 and the outer contact slit 16 in the longitudinal direction are set to have lengths so as to overlap each other in the radial direction.
Further, the fixed side contact portion 6 provided at the end of the fixed side energizing shaft 5 also has the same structure as the movable side contact portion 7.
The vacuum valve contact described in the present invention corresponds to the fixed side contact portion 6 and the movable side contact portion 7, and the vacuum container described in the present invention is fixed to the tubular vacuum insulating container 2. It corresponds to the side sealing metal fitting 3 and the movable side sealing metal fitting 4.

Next, the operation of the vacuum valve 1 of the first embodiment will be described.
When an arc is generated between the fixed side contact portion 6 and the movable side contact portion 7 when the current is cut off, the cylindrical portion 12 of the cup-shaped electrode 10 of the fixed side contact portion 6 and the movable side contact portion 7 is axially On the other hand, since a plurality of electrode slits 14 that cross diagonally are formed, a current in the circumferential direction flows through the cylindrical portion 12. As a result, a magnetic field (vertical magnetic field) parallel to the arc generated between the contact plate 11 of the fixed side contact portion 6 and the movable side contact portion 7 is applied. In this way, when a longitudinal magnetic field is applied to the arc, the arc is diffused and stabilized, and the arc voltage between the contact plate 11 of the fixed side contact portion 6 and the movable side contact portion 7 is reduced.

Here, the arc spot generated at the center position of the contact plate 11 of the fixed side contact portion 6 and the movable side contact portion 7 diffuses to the outer peripheral side of the contact plate 11.
Since the contact plate 11 is formed with two inner contact slits 15 and two outer contact slits 16 over the entire circumference of the contact plate 11 so as to surround the central position, it is formed on the outer peripheral side of the contact plate 11. The diffused arc spot flows into either the inner contact slit 15 or the outer contact slit 16 and disappears.
Then, when the arc spot generated at the center position of the contact plate 11 of the fixed side contact portion 6 also diffuses to the outer peripheral side of the contact plate 11, any of the inner contact slits 15 and two formed in the contact plate 11 It flows into the outer contact slit 16 of the above and disappears.

Next, the effect of the vacuum valve 1 of the first embodiment will be described.
According to the vacuum valve 1 of the first embodiment, when an arc is generated between the fixed side contact portion 6 and the movable side contact portion 7 when the current is cut off, the fixed side contact portion 6 and the fixed side contact portion 6 in which a plurality of electrode slits 14 are formed are formed. When a current flows in the circumferential direction through the cylindrical portion 12 of the electrode 10 of the movable side contact portion 7, a longitudinal magnetic field is applied to the arc generated in the fixed side contact portion 6 and the movable side contact portion 7. As a result, the arc is diffused, and the arc voltage between the contact plate 11 of the fixed side contact portion 6 and the movable side contact portion 7 is reduced, so that the arc blocking property can be improved.

At the same time, the arc spot generated at the center position of the contact plate 11 of the fixed side contact portion 6 and the movable side contact portion 7 diffuses to the outer peripheral side of the contact plate 11, and the inner contact slit 15 and the inner contact slit 15 formed in the contact plate 11 It disappears early by flowing into the outer contact slit 16.
Therefore, by extinguishing the arc spot on the contact plate 11 at an early stage, the bellows 9 is not thermally affected and the airtightness inside the vacuum insulating container 2 is not impaired.
Further, by forming the inner contact slit 15 and the outer contact slit 16 so that both ends in the longitudinal direction of each other overlap each other in the radial direction, the contact slits are provided over the outer periphery of the contact plate 11. The arc spot generated at the center position of the contact plate 11 can be surely extinguished.

[Second Embodiment]
Next, FIGS. 4 to 6 show the movable side contact portion 7 constituting the vacuum valve 1 of the second embodiment. The same components as those shown in the vacuum valve 1 of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.
As shown in FIG. 4, the movable side contact portion 7 of the second embodiment has a cup-shaped electrode 10 fixed to the end of the movable side energizing shaft 8 in the vacuum insulating container 2 and an opening of the electrode 10. It is provided with a disk-shaped contact plate 20 which is closed and fixed.

An annular contact groove 21 is formed on the outer peripheral side of the contact plate 20.
As shown in FIG. 5, the annular contact groove 21 is a groove formed by forming the upper surface of the contact plate 20 as a rectangular (square or rectangular) recess, and the inner peripheral side groove opening edge 21a and the outer circumference of the contact groove 21. The gutter opening edge 21b is formed as a right-angled corner. A groove bottom opening 21c is formed in a part of the bottom of the contact groove 21, and the groove bottom opening 21c and the upper ends of the plurality of electrode slits 14 formed in the electrodes 10 are in communication with each other. , The contact plate 20 is fixed to the opening of the electrode 10.

Further, the fixed side contact portion 6 of the second embodiment provided at the end of the fixed side energizing shaft 5 also has the same structure as the movable side contact portion 7.
Next, the operation when an arc spot is generated at the center position of the contact plate 20 of the movable side contact portion 7 of the second embodiment will be described.
As shown in FIG. 6A, the arc spot 22 generated at the center position of the contact plate 20 diffuses to the outer circumference of the contact plate 20, and the arc voltage of the arc 23 immediately before flowing into the contact groove 21 is maintained. Has been done.

Then, as shown in FIG. 6B, when the arc spot 22 flows into the contact groove 21 and the arc 23 comes into contact with the inner peripheral gutter opening edge 21a, it is between the arc spot 22 and the inner gutter opening edge 21a. Since they have the same potential, the arc 23 cannot maintain the arc voltage and disappears.
As a result, the arc spot 22 disappears on the outer peripheral side of the contact plate 20.
Further, in the fixed side contact portion 6 having the same structure as the movable side contact portion 7 of the second embodiment, the generated arc spot 22 disappears on the outer peripheral side of the contact plate 20.

Next, the effect of the vacuum valve 1 of the second embodiment will be described.
The arc spot 22 generated at the center position of the contact plate 20 of the fixed side contact portion 6 and the movable side contact portion 7 diffuses to the outer peripheral side of the contact plate 20 and forms an annular contact on the outer peripheral side of the contact plate 20. It disappears early by flowing into the groove 21.
Therefore, also in the second embodiment, since the arc spot 22 is extinguished on the contact plate 20 at an early stage, the bellows 9 is not thermally affected and the airtightness inside the vacuum insulating container 2 is not impaired.

[Modified example of the second embodiment]
Here, as another shape of the contact groove formed in the contact plate 20, there are those shown in FIGS. 7 and 8.
The annular contact groove 24 formed on the outer peripheral side of the contact plate 20 shown in FIG. 7A is a groove formed by forming the upper surface of the contact plate 20 as a right-angled triangular recess, and is on the side where the arc spot 22 flows. The inner peripheral side opening edge portion 24a is formed by an obtuse-angled corner portion.

The groove opening edge portion located on the central side of the contact plate described in the present invention corresponds to the inner peripheral side opening edge portion 24a.
In the contact groove 24 shown in FIG. 7A, the electric field concentration is relaxed because the inner peripheral side opening edge 24a on the side where the arc spot 22 flows is formed at an obtuse angle. As a result, the arc spot 22 can easily flow into the contact groove 24 immediately.

Then, as shown in FIG. 7B, when the arc spot 22 flows into the contact groove 24 and the arc 23 comes into contact with the inner peripheral side opening edge portion 24a, it is between the arc spot 22 and the inner peripheral side opening edge portion 24a. Since they have the same potential, the arc 23 cannot maintain the arc voltage and disappears. As a result, the arc spot 22 disappears on the outer peripheral side of the contact plate 20.
Further, the annular contact groove 25 formed on the outer peripheral side of the contact plate 20 shown in FIG. 8A is a groove formed with the upper surface of the contact plate 20 as a recess, and is an inner circumference on the side through which the arc spot 22 flows. The side opening edge portion 25a is formed in a shape that is rounded and projects outward.

The groove opening edge portion located on the central side of the contact plate described in the present invention corresponds to the inner peripheral side opening edge portion 25a.
Since the inner peripheral side opening edge 25a of the contact groove 25 shown in FIG. 8A is formed in a rounded shape so as to project outward, the electric field concentration is relaxed. As a result, the arc spot 22 can easily flow into the contact groove 25 immediately.

Then, as shown in FIG. 8B, when the arc spot 22 flows into the contact groove 25 and the arc 23 comes into contact with the inner peripheral side opening edge portion 25a, it is between the arc spot 22 and the inner peripheral side opening edge portion 25a. Since they have the same potential, the arc 23 cannot maintain the arc voltage and disappears. As a result, the arc spot 22 disappears on the outer peripheral side of the contact plate 20.
Therefore, by adopting the shape of the contact grooves 24 and 25 shown in FIGS. 7 and 8, the electric field concentration at the inner peripheral side opening edge portions 24a and 25a is relaxed, and the arc spot 22 is formed in the contact grooves 24 and 25 in a short time. Since it flows in, the extinction time of the arc 23 can be shortened, and the blocking property of the arc 23 can be further improved.

[Third Embodiment]
Next, FIGS. 9 and 10 show the vacuum valve 1 of the third embodiment.
The fixed-side contact portion 6 and the movable-side contact portion 7 of the vacuum valve 1 of the third embodiment have a cup-shaped electrode 10 and a disk-shaped contact plate 26 in which the opening of the electrode 10 is closed and fixed. I have.
As shown in FIG. 10, in the contact plate 26 of the movable side contact portion 7, a circular hole 27a is formed in the central portion, and a plurality of contact slits 27b are formed from the periphery of the hole 27a toward the outer peripheral side. ing.

A conductive ring member 28 is fixed to the movable side energizing shaft 8 whose end is fixed to the electrode 10 of the movable side contact portion 7 at an outer peripheral position not covered by the bellows 9.
The ring member 28 includes a disc portion 28a extending radially outward from the outer circumference of the movable side energizing shaft 8 and a cylindrical folded portion 28b extending from the outer circumference of the disc portion 28a to the electrode 10 side. , Is equipped.

Further, the contact plate 26 of the fixed side contact portion 6 is also formed with a circular hole 27a and a plurality of contact slits 27b.
Next, the operation when an arc spot is generated at the center position of the contact plate 26 of the movable side contact portion 7 of the third embodiment will be described with reference to FIG.
The arc spot 22 generated in the contact plate 26 of the movable side contact portion 7 moves to the movable side energizing shaft 8 side along the outer peripheral surface of the electrode 10 (cylindrical portion 12).

The arc spot 22 that has moved to the movable side energizing shaft 8 moves toward the bellows 9, but enters the disk portion 28a of the ring member 28 provided on the outer circumference of the movable side energizing shaft 8. Then, even if the arc spot 22 that has entered the disk portion 28a of the ring member 28 moves to the outer peripheral side of the disk portion 28a, it cannot go out due to the cylindrical folded portion 28b, and the arc voltage can be maintained. It disappears without.

Next, the effect of the vacuum valve 1 of the third embodiment will be described.
The arc spot 22 generated at the center position of the contact plate 26 of the movable side contact portion 7 diffuses to the outer peripheral side of the contact plate 26, and goes from the outer peripheral surface of the electrode 10 toward the bellows 9 along the movable side energizing shaft 8. However, it enters the disk portion 28a of the ring member 28 provided on the outer circumference of the movable side energizing shaft 8, cannot go out, and disappears.
Therefore, also in the third embodiment, since the arc spot 22 is extinguished in the middle of the movable side energizing shaft 8, the bellows 9 is not thermally affected and the airtightness inside the vacuum insulating container 2 is not impaired. ..

1 Vacuum valve 2 Vacuum insulated container 3 Fixed side sealing metal fittings 4 Movable side sealing metal fittings 5 Fixed side energizing shaft 6 Fixed side contact part 7 Movable side contact part 8 Movable side energizing shaft 9 Bellows 10 Electrode 11 Contact plate 12 Cylindrical part 13 Bottom 14 Electrode slit 15 Inner contact slit 16 Outer contact slit 20 Contact plate 21 Contact groove 21a Inner peripheral groove opening edge 21b Outer peripheral groove opening edge 21c Groove bottom opening 22 Arc spot 23 Arc 24 Contact groove 24a Inner peripheral opening edge Part 25 Contact groove 25a Inner peripheral opening edge 26 Contact plate 27a Circular hole 27b Contact slit 28 Ring member 28a Disk 28b Folded part P Radius center

Claims (5)

An electrode having a cylindrical portion and a disk-shaped contact plate that closes an opening on one end side of the cylindrical portion are provided.
A plurality of electrode slits that are inclined in the axial direction are formed on the peripheral surface of the cylindrical portion so as to be separated from each other in the circumferential direction.
A contact for a vacuum valve, characterized in that an annular contact groove is formed on the outer peripheral side of the contact surface of the contact plate. The contact for a vacuum valve according to claim 1, wherein the contact groove is formed as a rectangular recess. The contact groove, together are formed as a triangular recess, groove opening edge which is located at the center side of the contact plate according to claim 1, characterized in that it is formed at an obtuse angle corner The contact for the vacuum valve described in. The claim is characterized in that the contact groove is formed as a concave portion, and the groove opening edge portion located on the central side of the contact plate is formed in a rounded shape so as to project outward. Item 1. The contact for a vacuum valve according to item 1. A vacuum valve according to any one of claims 1 to 4, wherein the vacuum valve contacts are mounted in a vacuum container as a pair of contact portions that can be brought into contact with each other .

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