Vacuum bottle for a switching device

Abstract

A vacuum bottle (1) for a switching device comprising a first electrode (5) and a second electrode (6), each comprising a contact portion (8), the second electrode (6) being movable in an axial direction (X) relative to the first electrode (5) between a closed position and an open position, and a bellows seal (10) located around a stem (7) of the second electrode (6), the bellows seal (10) being adapted to conduct an electric current between an exterior of the vacuum bottle (1) and the contact portion (8) of the second electrode (6) when the second electrode (6) is in the closed position.

Description

Technical Field

[0001] The present invention relates to a vacuum bottle for a switching device and a switching device comprising such a vacuum bottle.

[0002] This invention is particularly applicable to switches where vacuum bottles are located on branches of the main current line. Background Technology

[0003] Vacuum bottles in circuits that allow current to be alternately interrupted or re-established by moving two electrodes relative to each other are known.

[0004] Therefore, current must flow between the electrodes of the vacuum bottle, which requires current to be conducted from the outside of the vacuum bottle to the inside of the vacuum bottle, while allowing at least one of the two electrodes to move.

[0005] This is relatively difficult to implement.

[0006] Therefore, the present invention aims to provide a switching device including a vacuum bottle that is less complex to manufacture, more compact, and less expensive to manufacture, allowing current to be satisfactorily conducted through the vacuum bottle. Summary of the Invention

[0007] The present invention improves this situation.

[0008] A vacuum bottle for a switching device is proposed, comprising:

[0009] Both the first and second electrodes include contact portions. The second electrode is axially movable relative to the first electrode between a closed position and an open position. In the closed position, the contact portions of the first and second electrodes are in contact with each other, allowing current to flow through the vacuum bottle. In the open position, the contact portions of the first and second electrodes are spaced apart, interrupting the current in the vacuum bottle. The second electrode includes a rod extending axially and terminating at the contact portion.

[0010] - A bellows seal located around the rod of the second electrode, designed to ensure a vacuum bottle seal while allowing the second electrode to move.

[0011] When the second electrode is in the closed position, the bellows seal is also adapted to conduct current between the outside of the vacuum bottle and the contact portion of the second electrode.

[0012] According to one embodiment, the vacuum bottle includes a conductive element adapted to conduct current between the exterior of the vacuum bottle and the contact portion of the second electrode when the second electrode is in the closed position, the bellows seal and the conductive element forming two current paths connected in parallel with each other.

[0013] According to another embodiment, the conductive element is a wire or a braided conductor.

[0014] According to another embodiment, the rod of the second electrode includes at least one segment made of an electrically insulating material.

[0015] According to another embodiment, the section of the rod of the second electrode made of an electrically insulating material is located outside the vacuum bottle and / or surrounded by a bellows seal.

[0016] According to another embodiment, the vacuum bottle includes a cap through which a second electrode is slidably mounted, and a bellows seal includes an end electrically connected to the cap and an end electrically connected to a contact portion of the second electrode.

[0017] According to another embodiment, the bellows seal is made of stainless steel, copper, and / or copper alloy.

[0018] According to another embodiment, the bellows seal includes a coating made of copper, obtained by electrolysis, plasma spraying, or cold spraying.

[0019] According to another embodiment, the thickness of the copper coating is greater than 0.05 mm, or even greater than 0.5 mm.

[0020] According to another embodiment, the bellows seal is made of copper-plated stainless steel.

[0021] According to another aspect, a switching device is proposed, which includes a vacuum bottle according to the invention, particularly for at least one of its electrical phases. Attached Figure Description

[0022] Other features, details, and advantages will become apparent from the description provided below and by consulting the accompanying drawings, in which:

[0023] Figure 1 This is a schematic cross-sectional view of a prior art vacuum bottle according to one embodiment.

[0024] Figure 2 This is a schematic cross-sectional view of a prior art vacuum bottle according to another embodiment.

[0025] Figure 3 This is a schematic cross-sectional view of a vacuum bottle according to an embodiment of the present invention.

[0026] Figure 4 This is a schematic cross-sectional view of a vacuum bottle according to another embodiment of the present invention.

[0027] Figure 5 This is a schematic cross-sectional view of a vacuum bottle according to another embodiment of the present invention. Detailed Implementation

[0028] The following figures and description largely contain elements that are essentially defined. Therefore, they can be used not only to better illustrate this disclosure, but also, where appropriate, to aid in its definition. In particular, the figures are cross-sectional views. However, it should be understood that many elements, such as the housing, lid, bellows seal, or electrodes of a vacuum bottle, have rotational symmetry about a central axis.

[0029] In the following text, the terms "upper" and "lower" are used only to indicate the relative positions of the components of the vacuum bottle as shown in the figure. However, it is understood that the vacuum bottle can be mounted in the switching device in any orientation.

[0030] Figure 3 A schematic example of a vacuum bottle 1 according to one embodiment of the invention is shown. The vacuum bottle 1 is intended for use as a switching device to interrupt current in a circuit, particularly in medium-voltage and / or high-voltage circuits.

[0031] In the following text, the terms “medium voltage” and “high voltage” are used in the generally accepted manner, that is, the term “medium voltage” refers to a voltage greater than 1,000 volts of AC and 1,500 volts of DC but not exceeding 52,000 volts of AC and 75,000 volts of DC, while the term “high voltage” refers to a voltage strictly greater than 52,000 volts of AC and 75,000 volts of DC.

[0032] In the following text, the term "switching device" refers to an electrical device used to interrupt current, such as a contactor, switch, fuse switch, or recloser. Other types of switching devices using vacuum bottles are also possible.

[0033] Vacuum bottle 1 can be used in switches as described in document EP2182536, particularly where the vacuum bottle is located on a branch of the main current line.

[0034] The vacuum bottle 1 includes a generally cylindrical outer shell 2 made of an electrically insulating material, preferably ceramic. The outer shell 2 is closed by two end caps, specifically an upper cap 3 and a lower cap 4. The outer shell 2 and the upper and lower caps 3 and 4 define an internal switching chamber that can be evacuated.

[0035] In the following text, the switch chamber refers to the interior of vacuum bottle 1, and the part not located in the switch chamber is the exterior of vacuum bottle 1.

[0036] The vacuum bottle 1 includes a first electrode 5 and a second electrode 6, which are at least partially housed inside the vacuum bottle 1. The first electrode 5 is stationary, specifically fixed to the lower cover 4, while the second electrode 6 is movable, specifically slidably mounted, so as to slide along the axial direction X inside the vacuum bottle 1 via the upper cover 3.

[0037] Each of the first and second electrodes 5 and 6 includes a rod 7 extending in the axial direction X toward the end 8 that forms the contact portion. Therefore, the rod 7 of the second electrode 6 is located both inside and outside the vacuum bottle 1. The end 8 that forms the contact portion can take various shapes and sizes, particularly in the form of a contact ball or pad with a relatively large radius of curvature.

[0038] The second electrode 6 can be slidable by an actuation mechanism (not shown in the figure) in a known manner. Therefore, the second electrode 6 can move between a closed position and an open position. Only the open position is shown in the figure. In the closed position, the contact portion 8 of the first electrode 5 and the contact portion 8 of the second electrode 6 are in contact with each other, allowing current to flow through the vacuum bottle 1. In the open position, the contact portions 8 of the first electrode 5 and the contact portions 8 of the second electrode 6 are spaced apart from each other, thus interrupting the current in the vacuum bottle 1.

[0039] The vacuum bottle 1 also includes a bellows seal 10. The bellows seal 10 is composed of a deformable tubular element. The bellows seal 10 is located around, or around at least a portion of, the rod 7 of the second electrode 6, particularly around a portion of the rod 7 located inside the vacuum bottle 1. The bellows seal 10 thus includes an end electrically connected to the top cover 3 and an end electrically connected to or near the contact portion 8 of the second electrode 6. For example, the bellows seal 10 is attached to the top cover 3 and the second electrode 6 by brazing.

[0040] The bellows seal 10, also known as a sealing bellows, is suitable for ensuring the airtightness of the vacuum bottle relative to the outside (especially for maintaining the vacuum inside the vacuum bottle 1) while allowing the second electrode 6 to slide.

[0041] The vacuum bottle 1 may also include a dielectric screen 11 placed around the contact portion 8 of the first and second electrodes 5, 6. Other screens, not shown, are also possible, such as an auxiliary screen around the bellows seal 10.

[0042] In demonstrating existing technology Figure 1 and Figure 2 In this configuration, current is conducted between the first electrode 5 and the second electrode 6 through a rod in the closed position, as shown by arrow C (illustrating the current flow when the second electrode is in the closed position). The rods of the first and second electrodes are therefore made of a conductive material.

[0043] according to Figure 1 The current flows from a current inlet 12 located outside the vacuum bottle. The current is then conducted through a flexible conductive wire or strip 12, for example, made of copper, to a rod of the second electrode. Thus, the wire allows current conduction while simultaneously allowing the rod of the second electrode to slide within the vacuum bottle.

[0044] according to Figure 2 As depicted, current flows from the current inlet 12 and is conducted through the conductive seal 15 to the rod of the second electrode. Therefore, the seal 15 allows current conduction while simultaneously allowing the rod of the second electrode to slide within the vacuum bottle.

[0045] However, these descriptions are not entirely satisfactory because they require additional components between the current inlet and the vacuum bottle, specifically to allow current to flow through the second electrode. These components can now be a source of failure, especially if the wires or seals are damaged or worn.

[0046] Therefore, according to Figure 3 , Figure 4 and Figure 5 As shown more specifically in the present invention, the bellows seal 10 is also adapted to conduct current between the current inlet 12 located outside the vacuum bottle 1 and the contact portion 8 of the second electrode 6.

[0047] The bellows seal 10 is therefore made of a conductive material, such as metal, particularly stainless steel. To ensure higher conductivity, especially for stainless steel, the bellows seal 10 may include a coating made of another material, such as copper, obtained particularly by electrolysis, plasma spraying, or cold spraying. The coating may advantageously have a thickness greater than 0.05 mm, or even greater than 0.5 mm.

[0048] According to another example, the bellows seal is made of copper-plated stainless steel. This bellows seal 10 is manufactured, for example, by roll forming.

[0049] Other embodiments of the bellows seal 10 can be used to ensure satisfactory conductivity, for example, by being made of copper or a copper alloy, such as, but not limited to, bronze, phosphor bronze, beryllium copper (CuBe), or bronze (CuSn8P or CuSn9P). Other alloys are also possible.

[0050] according to Figure 3 In one embodiment, all or almost all of the current is conducted through the bellows seal 10 to the contact portion 8 of the second electrode 6, as shown by arrow C (showing the current flow when the second electrode is in the closed position).

[0051] According to this embodiment, the current inlet 12 is electrically connected, for example, to the top cover 3 of the vacuum bottle 1. Current can then flow from the current inlet 12, through the top cover 3, through the bellows seal 10, through the contact portion 8 of the second electrode 6, through the first electrode 5, and then through the current outlet 14. The current outlet 14 is located outside the vacuum bottle 1, for example, electrically connected to the first electrode 5 of the vacuum bottle 1.

[0052] according to Figure 4 and Figure 5In a more particular embodiment shown, the vacuum bottle 1 may also include an additional conductive element 16 adapted to conduct current between the current inlet 12 located outside the vacuum bottle 1 and the contact portion 8 of the second electrode 6.

[0053] The conductive element 16 can be, for example, a flexible metal braided conductor or wire made of copper. However, these examples are not limiting and other embodiments are possible.

[0054] According to one embodiment, the conductive element 16 can be located in the switch chamber between the bellows seal 10 and the housing 2, such as... Figure 4 As shown. According to another embodiment, the conductive element 16 may be located between the rod 7 of the second electrode 6 and the bellows seal 10, as... Figure 5 As shown, this further allows local perturbations of the electric field to be limited.

[0055] The conductive element 16 includes an end electrically connected to the top cover 3 or the current inlet 12. The conductive element 16 also includes an end electrically connected to the contact portion 8 of the second electrode 6 or near the contact portion 8 of the second electrode 6, particularly by brazing or welding. The bellows seal 10 and the conductive element 16 thus form two current paths connected in parallel to each other outside the vacuum bottle and between the contact portion 8 of the second electrode 6.

[0056] according to Figure 4 and Figure 5 In this embodiment, the current is conducted simultaneously by the conductive element 16 and the bellows seal 10, as shown by arrow C (showing the current flow when the second electrode is in the closed position).

[0057] The statement "current is conducted simultaneously by conductive element 16 and bellows seal 10" can be understood as the current being distributed between them in a variable proportion as it flows into vacuum bottle 1, depending on their local resistivity. At least 5%, or even 10%, or even 20% of the current flows through bellows seal 10.

[0058] Then, the current can flow from the current inlet 12, through the top cover 3, then simultaneously through the bellows seal 10 and the conductive element 16, through the contact portion 8 of the second electrode 6, through the first electrode 5, and then through the current outlet 14.

[0059] According to the present invention, current does not flow through the rod 7 of the second electrode 6 or only through a segment of the rod 7 of the second electrode 6. Thus, in Figure 3 , Figure 4 and Figure 5The rod 7, shown in shaded lines, need not be made entirely or partially of a conductive material. Therefore, a portion of the rod 7 can be made of a relatively inexpensive electrically insulating material, thus avoiding the dielectric limitations associated with using conductive materials that readily influence the electric field inside the vacuum bottle. The section made of insulating material is advantageously surrounded by a bellows seal 10 and can be longer or shorter depending on the size of the bellows seal 10 used in the axial direction X.

[0060] Furthermore, with this invention, no additional components, such as those in the prior art, are required. Figure 1 and Figure 2 The conductive seals or wires shown are examples. This leads to a technical solution that includes fewer parts, making it more compact and less expensive to manufacture.

[0061] Of course, the present invention is not limited to the embodiments described above, which are provided merely as examples. It includes various modifications, alternative embodiments, and other variations that can be conceived by those skilled in the art within the context of the present invention, especially any combination of the various operating modes described above, which may be employed individually or in combination.

Claims

1. A vacuum bottle (1) for a switching device, comprising: - The first electrode (5) and the second electrode (6) both include contact portions (8). The second electrode (6) is movable relative to the first electrode (5) in the axial direction (X) between a closed position and an open position. In the closed position, the contact portions (8) of the first electrode (5) and the second electrode (6) are in contact with each other, allowing current to flow through the vacuum bottle (1). In the open position, the contact portions (8) of the first electrode (5) and the second electrode (6) are spaced apart, interrupting the current in the vacuum bottle (1). The second electrode (6) includes a rod (7) extending in the axial direction (X) and terminating at the contact portion (8). - A bellows seal (10) located around the rod (7) of the second electrode (6) is adapted to ensure the vacuum bottle is sealed while allowing the second electrode to move. The feature is that, when the second electrode (6) is in the closed position, the bellows seal (10) is also adapted to conduct current between the outside of the vacuum bottle (1) and the contact portion (8) of the second electrode (6); The vacuum bottle includes a conductive element (16) adapted to conduct current between the outside of the vacuum bottle (1) and the contact portion (8) of the second electrode (6) when the second electrode (6) is in the closed position. The bellows seal (10) and the conductive element (16) form two current paths connected in parallel to each other, and the conductive element is located between the rod of the second electrode and the bellows seal.

2. The vacuum bottle (1) according to claim 1, wherein, The conductive element (16) is a wire or a braided conductor.

3. The vacuum bottle (1) according to claim 1 or 2, wherein, The rod (7) of the second electrode (6) includes at least one segment made of an electrically insulating material.

4. The vacuum bottle (1) according to claim 3, wherein, The section of the rod (7) of the second electrode (6) made of electrical insulating material is located outside the vacuum bottle (1) and / or surrounded by the bellows seal (10).

5. The vacuum bottle (1) according to any one of claims 1-2 and 4, comprising a cap (3) through which the second electrode (6) is slidably mounted, the bellows seal (10) comprising an end electrically connected to the cap (3) and an end electrically connected to a contact portion (8) of the second electrode (6).

6. The vacuum bottle (1) according to any one of claims 1-2 and 4, wherein, The bellows seal (10) is made of stainless steel, copper and / or copper alloy.

7. The vacuum bottle (1) according to any one of claims 1-2 and 4, wherein, The bellows seal (10) includes a copper coating obtained by electrolysis, plasma spraying or cold spraying.

8. The vacuum bottle (1) according to claim 7, wherein, The coating thickness is greater than 0.05 mm.

9. The vacuum bottle (1) according to claim 8, wherein, The coating thickness is greater than 0.5 mm.

10. The vacuum bottle (1) according to any one of claims 1-2, 4 and 8-9, wherein, The bellows seal (10) is made of copper-plated stainless steel.

11. A switching device comprising a vacuum bottle (1) according to any one of the preceding claims.

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