JPS6312334B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum sheath breaker, and more particularly to a vacuum sheath breaker which enables uniform arc discharge in the absence of a magnetic field to cut a large current.

Conventionally, in order to achieve uniform arc discharge in the absence of a magnetic field to achieve high current breaker, a vacuum vessel was formed by airtightly closing both ends of an insulating cylinder with metal end plates, and the inside of this vacuum vessel was A pair of electrodes is provided so as to be able to move toward and away from each other through a pair of electrode rods that are introduced so as to be positioned on the axis so that they can move toward and away from each other, and each electrode and each electrode rod are arranged concentrically. A so-called rod array type vacuum shield breaker is known in which a plurality of axial rods surrounding the rod are properly spaced apart in the circumferential direction and are alternately fixed to opposing metal end plates. However, with rod array type vacuum shield breakers, arc discharge occurs in the circumferential direction between adjacent rods, so although it is possible to cut a large current of approximately 10 KA or more, the arc discharges at the ends of the rods. In order to prevent this from occurring in a concentrated manner, each rod is tapered so that the diameter becomes larger at the end, and the end is formed into an almost hemispherical shape, so it takes a considerable amount of man-hours to manufacture the rods. There are economic and other issues.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a discharge electrode for arc discharge which can be easily manufactured and which can further improve the arc discharge capacity. Our goal is to provide vacuum shields and disconnectors for large currents. Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a vacuum sheath disconnector according to the present invention. In the figure, generally indicated by 1 is a vacuum container, in which two insulating cylinders 2 formed in a cylindrical shape from an inorganic insulating material such as glass or ceramic are coaxially connected via sealing fittings 3 implanted at both ends of each insulating cylinder 2. The tube is joined to form a single insulating tube, both ends of which are hermetically closed via disk-shaped metal end plates 4, and the inside is evacuated to a high vacuum. Vacuum container 1
The fixed electrode rod 5 is inserted into the metal end plate 5 on the axis thereof, passing through the center of one (upper side in FIG. 1) of the metal end plate 4 and being airtightly fixed thereto. A movable electrode rod 6 is introduced into the center of the other metal end plate 4 via a bellows 7 so that it can move toward and away from the electrode rod 5 in the axial direction while maintaining airtightness by an operating device (not shown). , a pair of electrodes 8 and 9 are attached to the inner ends of the respective electrode rods 5 and 6, and are brought into contact and separated (contacted and separated) by movement of the movable electrode rod 6.

Inside the vacuum container 1, respective electrode rods 5,
Cylindrical first discharge electrodes 10 and 11 are arranged facing each other so as to concentrically surround the discharge electrodes 6 and the electrodes 8 and 9. Each of the first discharge electrodes 10 and 11 is used to perform arc discharge in the radial direction under a non-magnetic field in conjunction with a second discharge electrode, which will be described later. It is electrically connected and fixed, and is formed into a double cylindrical shape made of thin plate material with the end curved outward in an arc shape and extending parallel to the base side. Insulating cylinders 12 and 13 made of an inorganic insulator are interposed between the outer parts 10a and 11a and the outer parts 10b and 11b to prevent a short circuit between the two sides.

Note that the outer portion 10 of each first discharge electrode 10, 11
As shown in FIG. 2, a plurality of slits 10c, 11c are provided in the slits 10c, 11c parallel to the axis of the vacuum vessel 1 near the curved portion, as shown in FIG. Yes, each insulating cylinder 1
2 and 13 are appropriately attached to the inner surface of each metal end plate 4.

Further, in the vacuum container 1, each first
A second discharge electrode 14 is arranged so as to concentrically surround the discharge electrodes 10 and 11. The second discharge electrode 14 has an intermediate outer side sandwiched between sealing fittings 3, 3 that join the two insulating tubes 2 to form the vacuum vessel 1, and has both ends curved inward and near the intermediate portion. It is formed into a double cylindrical shape made of thin plates facing each other and extending parallel to the inner part 14.
a and the outer part 14b, each of the first discharge electrodes 1
Similarly to Nos. 0 and 11, an insulating tube 15 made of a non-insulating material is interposed, which is supported by the sealing fittings 3, 3 via a support member (not shown) in order to prevent a short circuit between both sides. As shown in FIG. 3, each of the first discharge electrodes 10, 1
A plurality of slits 14c are provided across the curved portion, facing the first slits 10c and 11c and parallel to the axis.

Note that the slits 10c, 11c, 14c of each of the first discharge electrodes 10, 11 and the second discharge electrode 14
may be omitted if arc discharge is uniform. Also, in Figure 1, 16
is a flexible lead wire for improving electrical connection between the other metal end plate 4 and the outer end of the movable electrode rod 6;
17, 17 are shields arranged around the outer periphery of the second discharge electrode 14 in order to prevent the inner surface of each insulating cylinder 2 constituting the vacuum container 1 from being contaminated by metal vapor.

In order to disconnect the electrodes 8 and 9 from the state where they are in contact and a large current is being applied with the above configuration, move the movable electrode rod 6 downward in FIG. , 9 are released. electrode 8,
9 separates, an initial arc is generated between the two, and metal vapor etc. diffused into the vacuum vessel 1 are triggered by this, and the outer parts 10b, 11b of each of the first discharge electrodes 10, 11 and the second Arc discharge is performed between the inner part 14a of the discharge electrode 14, and the arc current flows through the movable electrode rod 5, one metal end plate 4, one first discharge electrode 10, and the second discharge electrode 1.
4, it flows through the other first discharge electrode 11, the other metal end plate 4, the flexible lead wire 16, and the movable electrode rod 6. And the first discharge electrodes 10, 11
When an arc discharge occurs between the electrode 8 and the second discharge electrode 14, the initial arc between the electrodes 8 and 9 disappears immediately.
This is the first discharge electrode 10, 11 and the second discharge electrode 1.
This is because the arc discharge between the electrodes 8 and 4 occurs over the entire circumference, and the sum of the arc voltages is much lower than the arc voltage of the initial arc generated between the electrodes 8 and 9. And the electrode rod 6 on the movable side
is separated from the fixed electrode rod 5 as shown in FIG. The large current is completely terminated by spontaneous extinction.

As described above, in the present invention, a vacuum container is formed by hermetically closing both ends of an insulating cylinder with metal end plates, and the insulating cylinder is introduced into the vacuum container so as to be positioned on the axis thereof so as to be able to approach and separate from the cylinder. A pair of electrodes is provided so as to be able to come and go freely through a pair of electrode rods, and the base part is fixed to each metal end plate in the vacuum container, and the end part is curved outward and parallel to the base side. Extended cylindrical first discharge electrodes are arranged facing each other so as to concentrically surround each electrode rod, and the middle portion is supported by an insulating tube within the vacuum container, and both ends are directed inward. Since the cylindrical second discharge electrodes are curved and extend parallel to each other near the middle portion and are opposed to each other, they are arranged so as to concentrically surround each of the first discharge electrodes. It can be easily manufactured by machining, and since arc discharge occurs on the entire circumferential surface, it has the advantage of further increasing the thermal capacity.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a vacuum sheath disconnector according to the present invention, and FIGS. 2 and 3 are half-cut cross-sectional views of essential parts of the present invention. 1... Vacuum container, 2... Insulating cylinder, 4... Metal end plate, 5, 6... Electrode rod, 8, 9... Electrode, 10,
11...first discharge electrode, 14...second discharge electrode.

Claims (1)

[Claims] 1. Both ends of an insulating tube are airtightly closed with metal end plates to form a vacuum container, and a pair of electrode rods are introduced into the vacuum container so as to be able to approach and separate from each other while being positioned on the axis of the vacuum container. A pair of electrodes are provided in the vacuum container so as to be able to come into contact with and separate from the electrodes, and a cylindrical shape having a base fixed to each metal end plate, an end curved outward, and extending parallel to the base side is provided in the vacuum vessel. First discharge electrodes are arranged facing each other so as to concentrically surround the respective electrode rods, and the middle part is supported by an insulating cylinder in the vacuum container, and both ends are curved inwardly and near the middle part. A vacuum shield breaker characterized in that cylindrical second discharge electrodes extending parallel to and facing each other are arranged so as to concentrically surround each first discharge electrode.