JP2021048029A - Vacuum valve - Google Patents

Abstract

To provide a vacuum valve capable of preventing deterioration of a degree of vacuum in a vacuum container.SOLUTION: A vacuum valve includes: a vacuum insulation container (2); a pair of electrodes (51 and 52) housed in the vacuum insulation container and structured so as to enable contact and separation; current-carrying shafts (41 and 42) conducted to each electrode; and an arc shield (8) arranged so as to surround each electrode. One part corresponding to an opposite surface of at least the pair of electrodes in the arc shield is structured by any one of titanium, barium, and magnesium.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vacuum valve with an arc shield.

Conventionally, in a vacuum valve, in order to prevent a decrease in the degree of vacuum in the vacuum vessel and maintain the breaking performance, at least of Ti, Zr and ZuH2 having a thickness of 0.2 μm or more on the facing surfaces of the pair of electrodes. A method for manufacturing a vacuum valve has been proposed in which a thin film layer containing one type of main component is formed, and at least a part of the thin film layer is vapor-deposited on at least one of an insulating cylinder inner surface and an arc shield inner surface by applying current aging. (See, for example, Patent Document 1).

Patent No. 2859932

However, in the method for manufacturing a vacuum valve described in Patent Document 1 described above, a part of the thin film layer formed on the facing surface of the electrode is vapor-deposited on the inner surface of an insulating cylinder or the like by current aging, so that one of the thin film layers. It is difficult to evenly deposit the portion on the inner surface of an insulating cylinder or the like. Therefore, a situation may occur in which a decrease in the degree of vacuum in the vacuum container cannot be prevented.

The present invention has been made in view of such circumstances, and one of the objects of the present invention is to provide a vacuum valve capable of surely preventing a decrease in the degree of vacuum in a vacuum container.

The vacuum valve of the present embodiment surrounds the vacuum insulating container, a pair of electrodes housed in the vacuum insulating container and configured to be detachable, an energizing shaft that energizes the electrodes, and the electrodes. It has an arranged arc shield, and is characterized in that a part of the arc shield corresponding to at least the facing surfaces of the pair of electrodes is made of titanium, barium, or magnesium.

The vacuum valve of the present embodiment surrounds the vacuum insulating container, a pair of electrodes housed in the vacuum insulating container and configured to be detachable, an energizing shaft that energizes the electrodes, and the electrodes. It has an arranged arc shield, and at least a part of the arc shield corresponding to the facing surfaces of the pair of electrodes is plated with any of titanium, barium, and magnesium.

According to the present invention, it is possible to surely prevent a decrease in the degree of vacuum in the vacuum container.

It is sectional drawing which shows the structure of the vacuum valve which concerns on 1st Embodiment. It is sectional drawing which shows the structure of the vacuum valve which concerns on 1st Embodiment. It is an enlarged view around the arc shield included in the vacuum valve which concerns on 1st Embodiment. It is an enlarged view around the arc shield included in the vacuum valve which concerns on 2nd Embodiment. It is an enlarged view around the arc shield included in the vacuum valve which concerns on 3rd Embodiment. It is an enlarged view around the arc shield included in the vacuum valve which concerns on 4th Embodiment.

(First Embodiment)
Hereinafter, embodiments of the vacuum valve according to the present invention will be described with reference to the drawings. 1 and 2 are cross-sectional views showing the configuration of the vacuum valve 1 according to the present embodiment. Note that FIG. 1 shows a case where the pair of electrodes (stator electrode 51 and mover electrode 52 described later) of the vacuum valve 1 are closed, and FIG. 2 shows the case where the pair of electrodes of the vacuum valve 1 are closed. The case where the electrode is opened is shown.

As shown in FIG. 1, the vacuum valve 1 has a vacuum insulating container 2 having a generally tubular shape. For example, the vacuum insulating container 2 has a cylindrical shape and has openings 21 and 22 at the vertical ends shown in FIGS. 1 and 2. The vacuum insulating container 2 is made of, for example, alumina ceramic, but is not limited thereto. A fixed-side sealing metal fitting (hereinafter, referred to as “fixed-side metal fitting”) 31 is joined to the opening 21 formed below the vacuum insulating container 2. On the other hand, a movable side sealing metal fitting (hereinafter, referred to as “movable side metal fitting”) 32 is joined to the opening 22 formed above the vacuum insulating container 2. For example, these fixed side metal fittings 31 and movable side metal fittings 32 are brazed to the openings 21 and 22 of the vacuum insulating container 2. Brazing joints can also be applied to the joints between the components of the vacuum valve 1 shown below.

A fixed-side energizing shaft 41 is joined to the fixed-side metal fitting 31. The fixed-side energizing shaft 41 penetrates and is fixed to the fixed-side metal fitting 31. The upper end of the bellows 6 is joined to the inner wall surface of the movable side metal fitting 32. The lower end of the bellows 6 is joined to the bellows cover 7 fixed to the movable side energizing shaft 42, which will be described later. The bellows 6 is formed of thin stainless steel in a bellows shape, and expands and contracts along the axial direction (vertical direction shown in FIGS. 1 and 2) of the vacuum insulating container 2.

The movable side energizing shaft 42 is attached so as to penetrate the movable side metal fitting 32 and the bellows cover 7. The penetrating portion of the movable side energizing shaft 42 is joined to the bellows cover 7. For example, the bellows cover 7 is made of stainless steel or the like, but is not limited thereto. The bellows cover 7 prevents the metal vapor generated by the arc generated when the current is cut off from adhering to the bellows 6. This prevents the bellows 6 from being contaminated with metal steam.

A fixed-side electrode 51 is joined to the end (upper end) of the fixed-side energizing shaft 41. A movable side electrode 52 is joined to an end portion (lower end portion) of the movable side energizing shaft 42. Inside the vacuum valve 1 (vacuum insulating container 2), the fixed side electrode 51 and the movable side electrode 52 are arranged so as to face each other. When the vacuum valve 1 is closed, the movable electrode 52 is in contact with the fixed electrode 51 (see FIG. 1), and when the vacuum valve 1 is opened, the movable electrode 52 is separated from the fixed electrode 51 (FIG. 1). 2). That is, the fixed side electrode 51 and the movable side electrode 52 (a pair of electrodes) are housed in the vacuum insulating container 2 and are configured to be removable.

An arc shield 8 is provided in the vacuum insulating container 2. The arc shield 8 generally has a tubular shape. The arc shield 8 is fixed in the vacuum insulating container 2 so as to surround the fixed side electrode 51 and the movable side electrode 52. The arc shield 8 prevents the metal vapor generated by the arc generated when the current is cut off from adhering to the inner wall surface of the vacuum insulating container 2. This prevents the dielectric strength of the inner wall surface of the vacuum insulating container 2 from decreasing.

In the vacuum valve 1 according to the first embodiment, the arc shield 8 is made of a metal material having a getter action. Here, the getter action refers to an action of exhausting gas molecules by adsorbing them. For example, the arc shield 8 is composed of titanium (Ti), barium (Ba), and magnesium (Mg). Here, it is assumed that the entire arc shield 8 (the entire tubular shape) is made of titanium.

The arc shield 8 has a small diameter portion 8a at an end portion in the vertical direction, and has a large diameter portion 8b between these small diameter portions 8a. The large diameter portion 8b is arranged at the central portion in the vertical direction of the arc shield 8. The arc shield 8 is arranged at a position where the large diameter portion 8b corresponds to the pair of electrodes (fixed side electrode 51 and movable side electrode 52). In particular, in the arc shield 8, the facing surfaces (upper surface 511 of the fixed side electrode 51 and lower surface 521 of the movable side electrode 52) when the fixed side electrode 51 and the movable side electrode 52 come into contact with each other are in the vertical direction of the arc shield 8. It is arranged so as to be located in the center (see FIG. 1).

The operation of the vacuum valve 1 having such a configuration at the time of opening the pole will be described with reference to FIGS. 1 to 3. FIG. 3 is an enlarged view of the periphery of the arc shield 8 included in the vacuum valve 1 according to the first embodiment. When shifting from the closed pole state shown in FIG. 1 to the open pole state shown in FIG. 2, the movable side energizing shaft 42 is pulled up as the bellows 6 shrinks. Along with this, the movable side electrode 52 moves upward and separates from the fixed side electrode 51.

When the movable side electrode 52 is separated from the fixed side electrode 51, an arc (not shown) is generated. This arc is generated by diffusing from the facing surfaces of the fixed side electrode 51 and the movable side electrode 52 (the upper surface 511 of the fixed side electrode 51 and the lower surface 521 of the movable side electrode 52), and a part of the arc is inside the arc shield 8. Contact the wall. When an arc comes into contact with the arc shield 8, a part of titanium constituting the arc shield 8 evaporates and titanium atoms are released. Alternatively, when the neutral particles and ions generated from the arc collide with the inner wall surface of the arc shield 8, titanium atoms are emitted from the surface of the arc shield 8.

Titanium atoms emitted from the arc shield 8 adhere to the surface of the fixed side electrode 51 and the fixed side energizing shaft 41, the surface of the movable side electrode 52 and the movable side energizing shaft 42, or the inner wall surface of the arc shield 8 and titanium. A film is formed. The titanium film formed in this way has a getter action. Therefore, the gas molecules released into the vacuum insulating container 2 from the electrode material or the like as the arc is generated are adsorbed by the titanium film. Therefore, it is possible to prevent a situation in which the degree of vacuum in the vacuum insulating container 2 is lowered due to the gas molecules generated with the generation of the arc.

As described above, in the vacuum valve 1 according to the first embodiment, since the arc shield 8 is made of titanium, a titanium film having a getter action is formed by utilizing the arc generated at the time of opening the pole, and the fixed side electrode 51 and the like. A film can be formed on the surface of the movable side electrode 52 or the like. As a result, the gas molecules released into the vacuum insulating container 2 can be quickly adsorbed by the titanium film, so that the decrease in the degree of vacuum in the vacuum insulating container 2 can be reliably prevented. As a result, the breaking performance of the vacuum valve 1 can be maintained.

In the first embodiment, the case where the entire arc shield 8 is made of titanium is described, but the portion (region) of the arc shield 8 made of titanium is not limited to this. It can be changed as appropriate. The portion (region) made of titanium in the arc shield 8 is formed on the facing surfaces (upper surface 511 of the fixed side electrode 51 and lower surface 521 of the movable side electrode 52) of the pair of electrodes (fixed side electrode 51 and movable side electrode 52). It can be set to any part (area) on condition that the corresponding part is included. Here, the part corresponding to the facing surfaces of the pair of electrodes is a portion (region) between the facing surface when the electrode is closed shown in FIG. 1 and the facing surface when the electrode is opened shown in FIG. Say.

For example, as an embodiment in which a part corresponding to the facing surfaces of the pair of electrodes is made of titanium, only the part (region) corresponding to the facing surfaces of the fixed side electrode 51 and the movable side electrode 52 is made of titanium, and other parts are made of titanium. The portion can be made of a metal material such as stainless steel. In this case, the large diameter portion 8b of the arc shield 8 is made of titanium, while the small diameter portion 8a is made of stainless steel, and these can be joined.

Further, the entire arc shield 8 is made of a metal material such as stainless steel, and a part corresponding to the facing surface of the pair of electrodes (fixed side electrode 51 and movable side electrode 52) is plated to form a titanium-plated portion. May be provided. Further, the entire inner wall surface of the arc shield 8 may be plated to provide a titanium-plated portion on the entire inner wall surface. Any plating process including electroplating and hot-dip galvanizing can be used for the plating process. Even in the case of changing as described above, the same effect as described above can be obtained.

Further, in the first embodiment, a case where a part or all of the arc shield 8 is made of titanium will be described. However, the material forming the arc shield 8 is not limited to titanium, and may be composed of barium (Ba) and magnesium (Mg). Even when replaced with these metal materials, the same effect as described above can be obtained.

(Second Embodiment)
The vacuum valve according to the second embodiment is different from the vacuum valve 1 according to the first embodiment in the configuration of the arc shield 8. Hereinafter, the configuration of the vacuum valve according to the second embodiment will be described with reference to FIG. 4, focusing on the differences from the vacuum valve 1 according to the first embodiment. FIG. 4 is an enlarged view of the periphery of the arc shield 8 included in the vacuum valve according to the second embodiment. In FIG. 4, the same reference numerals are given to the configurations common to the vacuum valve 1 according to the first embodiment, and the description thereof will be omitted.

As shown in FIG. 4, the arc shield 8 according to the second embodiment has a titanium tubular body (hereinafter, referred to as “titanium tubular body”) 81. The titanium tubular body 81 is joined (for example, brazed) inside the large diameter portion 8b. In this case, the titanium tubular body 81 is arranged at a position corresponding to the facing surface of the pair of electrodes (fixed side electrode 51 and movable side electrode 52). In the second embodiment, the portion of the arc shield 8 other than the titanium tubular body 81 can be made of, for example, stainless steel, but is not limited thereto.

As described above, in the vacuum valve according to the second embodiment, the titanium tubular body 81 is joined to a part corresponding to the facing surfaces of the fixed side electrode 51 and the movable side electrode 52 in the arc shield 8. Therefore, similarly to the arc shield 8 according to the first embodiment, a titanium film having a getter action is formed on the surface of the fixed side electrode 51, the movable side electrode 52, etc. by utilizing the arc generated at the time of opening the pole. can do. As a result, the gas molecules released into the vacuum insulating container 2 can be quickly adsorbed by the titanium film, so that the decrease in the degree of vacuum in the vacuum insulating container 2 can be reliably prevented.

In particular, in the vacuum valve according to the second embodiment, since the titanium tubular body 81 is joined to a part of the arc shield 8, titanium in the arc shield 8 is compared with the first embodiment. The amount of water used can be reduced. As a result, the cost required for manufacturing the arc shield 8 can be reduced.

In the embodiment in which the titanium tubular body 81 is joined in this way, it is preferable that the arc shield 8 other than the titanium tubular body 81 is composed of a plurality of parts. For example, it is an embodiment that the arc shield 8 other than the titanium tubular body 81 is divided into two in the vertical direction or the horizontal direction, and the two parts are integrated with the titanium tubular body 81 housed inside. Is preferable. In this case, the work efficiency at the time of manufacturing the arc shield 8 can be improved. Note that FIG. 4 shows an example in which the arc shield 8 other than the titanium tubular body 81 is divided into two in the vertical direction. The arc shield 8 other than the titanium tubular body 81 is divided in the vertical direction at the lower portion of the large diameter portion 8b.

(Third Embodiment)
The vacuum valve according to the third embodiment is different from the vacuum valve according to the second embodiment in the configuration of the arc shield 8. Hereinafter, the configuration of the vacuum valve according to the third embodiment will be described with reference to FIG. 5, focusing on the differences from the vacuum valve according to the second embodiment. FIG. 5 is an enlarged view of the periphery of the arc shield 8 included in the vacuum valve according to the third embodiment. In FIG. 5, the same reference numerals are given to the configurations common to the vacuum valve 1 according to the first embodiment, and the description thereof will be omitted. Further, in FIG. 5, for convenience of explanation, the fixed side electrode 51, the movable side electrode 52, and the like are omitted.

As shown in FIG. 5, a plurality of titanium annular bodies (hereinafter referred to as “titanium annular bodies”) 82 are joined to the inner wall surface of the large diameter portion 8b to the arc shield 8 according to the third embodiment (hereinafter, referred to as “titanium annular body”). For example, it is brazed (bonded). These titanium annular bodies 82 are arranged at intervals in the vertical direction (moving direction of the movable side electrode 52) so as to correspond to the facing surfaces of the fixed side electrode 51 and the movable side electrode 52. In the third embodiment, the portion of the arc shield 8 other than the titanium annular body 82 can be made of, for example, stainless steel, but is not limited thereto.

As described above, in the arc shield 8 according to the third embodiment, the titanium annular body 82 is bonded to a part corresponding to the facing surfaces of the fixed side electrode 51 and the movable side electrode 52. Therefore, similarly to the arc shield 8 according to the first embodiment, a titanium film having a getter action is formed on the surface of the fixed side electrode 51, the movable side electrode 52, etc. by utilizing the arc generated at the time of opening the pole. can do. As a result, the gas molecules released into the vacuum insulating container 2 can be quickly adsorbed by the titanium film, so that the decrease in the degree of vacuum in the vacuum insulating container 2 can be reliably prevented.

In particular, in the vacuum valve according to the third embodiment, a plurality of titanium annular bodies 82 are placed on the inner wall surface of the large diameter portion 8b at intervals in the moving direction (vertical direction shown in FIG. 5) of the movable side electrodes 52. It is joined. In other words, in the vacuum valve according to the third embodiment, the titanium portion (region) formed in the arc shield 8 is divided into a plurality of regions arranged along the moving direction of the movable side electrode 52. ing. Therefore, the amount of titanium used for the arc shield 8 can be reduced as compared with the second embodiment. Thereby, the cost required for manufacturing the arc shield 8 can be further reduced.

The arc shield 8 according to the third embodiment shows a case where the titanium annular body 82 is joined to the inner wall surface of the large diameter portion 8b at regular intervals. Generally, the arc generated at the time of opening is around the position where the movable side electrode 52 is separated from the fixed side electrode 51 (that is, the position corresponding to the facing surface of the fixed side electrode 51 and the movable side electrode 52 shown in FIG. 2). Easy to concentrate. Therefore, the distance between the titanium annular bodies 82 may be increased as the distance between the fixed side electrode 51 and the movable side electrode 52 is increased. In this case, the amount of titanium used for the arc shield 8 can be reduced while maintaining the action of preventing the degree of vacuum in the vacuum insulating container 2 from decreasing.

(Fourth Embodiment)
The vacuum valve according to the fourth embodiment is different from the vacuum valve according to the third embodiment in the configuration of the arc shield 8. Hereinafter, the configuration of the vacuum valve according to the fourth embodiment will be described with reference to FIG. 6, focusing on the differences from the vacuum valve according to the third embodiment. FIG. 6 is an enlarged view of the periphery of the arc shield 8 included in the vacuum valve according to the fourth embodiment. In FIG. 6, the same reference numerals are given to the configurations common to the vacuum valve 1 according to the first embodiment, and the description thereof will be omitted. Further, in FIG. 6, for convenience of explanation, the fixed side electrode 51, the movable side electrode 52, and the like are omitted.

As shown in FIG. 6, on the inner wall surface of the arc shield 8 according to the fourth embodiment, in addition to a plurality of (here, two) titanium annular bodies 82, a plurality of titanium long bodies (hereinafter referred to as , "Titanium long body") 83 is joined (for example, brazed joint). The titanium annular body 82 is arranged around a position corresponding to a facing surface between the fixed side electrode 51 and the movable side electrode 52. Further, the titanium elongated body 83 is arranged outside the titanium annular body 82 (outside in the vertical direction shown in FIG. 6). The length of the titanium elongated body 83 is shortened as the distance from the titanium annular body 82 increases. In the vacuum valve according to the fourth embodiment, the portion of the arc shield 8 other than the titanium annular body 82 and the titanium elongated body 83 can be made of, for example, stainless steel, but is not limited thereto. ..

As described above, in the arc shield 8 according to the fourth embodiment, the titanium annular body 82 and the titanium elongated body 83 are joined to a part corresponding to the facing surfaces of the movable side electrode 52 and the movable side energizing shaft 42. There is. Therefore, similarly to the arc shield 8 according to the first embodiment, a titanium film having a getter action is formed on the surface of the fixed side electrode 51, the movable side electrode 52, etc. by utilizing the arc generated at the time of opening the pole. can do. As a result, the gas molecules released into the vacuum insulating container 2 can be quickly adsorbed by the titanium film, so that the decrease in the degree of vacuum in the vacuum insulating container 2 can be reliably prevented.

In particular, in the arc shield 8 according to the fourth embodiment, a titanium elongated body 83 is joined to the inner wall surface instead of a part of the titanium annular body 82. In other words, in the arc shield 8 according to the fourth embodiment, the titanium portion (region) formed on the arc shield 8 is located at a position where the movable side electrode 52 is separated from the fixed side electrode 51 (that is, FIG. 2). The position becomes smaller as the distance from the fixed side electrode 51 and the movable side electrode 52 (positions corresponding to the facing surfaces) is increased. Therefore, the amount of titanium used for the arc shield 8 can be reduced as compared with the third embodiment. Thereby, the cost required for manufacturing the arc shield 8 can be further reduced.

Generally, the arc generated at the time of closing is around the position where the movable side electrode 52 is separated from the fixed side electrode 51 (that is, the position corresponding to the facing surface of the fixed side electrode 51 and the movable side electrode 52 shown in FIG. 2). Easy to concentrate. Therefore, the distance between the titanium annular body 82 and the titanium elongated body 83 may be increased as the distance between the fixed side electrode 51 and the movable side electrode 52 is increased. In this case, the amount of titanium used for the arc shield 8 can be reduced while maintaining the action of preventing the degree of vacuum in the vacuum insulating container 2 from decreasing.

The present invention is not limited to the above embodiment, and can be modified in various ways. In the above embodiment, the size, shape, function, and the like of the components shown in the accompanying drawings are not limited to this, and can be appropriately changed within the range in which the effects of the present invention are exhibited. In addition, it can be appropriately modified and implemented as long as it does not deviate from the scope of the object of the present invention.

For example, in the above embodiment, a part of the arc shield 8 is made of titanium, barium, or magnesium, or a part of the arc shield 8 is plated with titanium, barium, or magnesium. Explains the case. However, the material of the arc shield 8 or the plating material for the arc shield 8 may be mixed with the above-mentioned materials, provided that the arc shield 8 exerts a getter action.

The vacuum valve of the present invention has an effect of being able to prevent a decrease in the degree of vacuum in the vacuum container, and is particularly applicable to a vacuum valve installed in any electric power facility.

1: Vacuum valve 2: Vacuum insulated container 21: Opening 22: Opening 31: Fixed side metal fitting 32: Movable side metal fitting 41: Fixed side energizing shaft 42: Movable side energizing shaft 51: Fixed side electrode 52: Movable side electrode 6 : Bellows 7: Bellows cover 8: Arc shield 8a: Small diameter part 8b: Large diameter part 81: Titanium tubular body 82: Titanium annular body 83: Titanium long body

Claims (6)

Vacuum insulated container and
A pair of electrodes housed in the vacuum insulating container and configured to be detachable,
An energizing shaft that energizes the electrodes and
It has an arc shield arranged so as to surround the electrode.
A vacuum valve characterized in that at least a part of the arc shield corresponding to the facing surfaces of the pair of electrodes is made of titanium, barium, or magnesium. Vacuum insulated container and
A pair of electrodes housed in the vacuum insulating container and configured to be detachable,
An energizing shaft that energizes the electrodes and
It has an arc shield arranged so as to surround the electrode.
A vacuum valve characterized in that at least a part of the arc shield corresponding to the facing surfaces of the pair of electrodes is plated with titanium, barium, or magnesium. The vacuum according to claim 1 or 2, wherein the region of titanium, barium, or magnesium in the arc shield is divided into a plurality of regions arranged along the moving direction of the electrode. valve. The vacuum valve according to claim 3, wherein the region of titanium, barium, or magnesium in the arc shield becomes smaller as the distance from the position corresponding to the facing surface of the electrode at the time of closing the electrode is increased. 3. The distance between the regions of titanium, barium, and magnesium in the arc shield increases as the distance from the position corresponding to the facing surface of the electrode at the time of closing the electrode increases. 4. The vacuum valve according to 4. The first aspect of the present invention, wherein the region of titanium, barium, or magnesium in the arc shield is formed by joining a tubular body made of the material to the inner wall surface of the arc shield. Vacuum valve.

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