Contact element of a vacuum interrupter, and vacuum interrupter

Abstract

The invention relates to a contact element (1) of a vacuum interrupter (40). The contact element (1) comprises an electrically conductive column-like contact stem (3) and an electrically conductive contact cup (5) having a cup base (15) and a cup wall (17) projecting from the cup base (15), wherein the cup base (15) has a base region (19) which is connected to an end face (7) of the contact stem (3). The contact element (1) also comprises an electrically conductive contact disc (6) which closes the contact cup (5) and is connected to the cup wall (17). The following each have at least one slot (11, 21, 25): an end region (9) of the contact stem (3) that includes the end face (7); the cup base (15); and the cup wall (17)

Description

[0001] 2024PF00924

[0002] 1

[0003] Description

[0004] Contact element of a vacuum switching tube and vacuum switching tube

[0005] The invention relates to a contact element of a vacuum switching tube and a vacuum switching tube.

[0006] A vacuum switching tube comprises a housing and two contact elements that are movable relative to each other. Typically, one contact element is a fixed contact, rigidly connected to the housing, and the other is a movable contact, movable relative to both the fixed contact and the housing. This movable contact can be positioned between a first switching position, in which it rests against the fixed contact within the housing, and a second switching position, in which it is separated from the fixed contact. Each contact element typically has an electrically conductive contact shaft and a plunger-like electrically conductive end piece connected to the contact shaft, to which an electric current can be supplied. In the first switching position, the end pieces of the two contact elements touch each other; in the second switching position, the end pieces of the two contact elements are separated.

[0007] The end pieces are usually made of metal. When the contact elements separate, metal vaporizes from the opposing surfaces of the end pieces, and a metal vapor arc forms between them. The shape and distribution of the metal vapor arc are influenced by the electromagnetic field, particularly the magnetic field, between the end pieces. The magnetic field is primarily caused by the electric currents flowing in the contact elements, which in turn can be influenced by the design of the contact elements. The aim is generally to achieve a metal vapor arc that is as diffuse and evenly distributed as possible between the end pieces. Since the contact shaft and the end piece of a contact element are made of 2024PF00924

[0008] 2

[0009] Because the contact elements consist of highly electrically conductive materials, eddy currents can be induced in the contact shaft and end piece by the magnetic field. These eddy currents oppose the magnetic field according to Lenz's law, thus weakening it and potentially leading to a phase shift between the generating current and the magnetic field. Both effects negatively impact the performance of the contact system formed by the contact elements.

[0010] The invention is based on the objective of providing a contact element for a vacuum switching tube that is improved with respect to the generated magnetic field. Furthermore, the invention is based on the objective of providing an improved vacuum switching tube.

[0011] The problem is solved according to the invention by a contact element with the features of claim 1 and a vacuum switching tube with the features of claim 15.

[0012] Advantageous embodiments of the invention are the subject of the dependent claims.

[0013] A contact element according to the invention of a vacuum switching tube comprises

[0014] - an electrically conductive column-like contact shaft, - an electrically conductive contact pot with a pot base and a pot wall projecting from the pot base, wherein the pot base has a base area that is connected to an end face of the contact shaft, and

[0015] - an electrically conductive contact disc that covers the contact pot and is connected to the pot wall, wherein - an end region of the contact shaft encompassing the end face, the pot bottom and the pot wall each have at least one slot.

[0016] Slots in the contact shaft, the cup base, and the cup wall reduce or prevent eddy currents that can be induced in these parts of the contact element. 2024PF00924

[0017] 3

[0018] This is made possible by the fact that each slot prevents an electric current that could otherwise flow between the areas of the contact element separated by the slot. Furthermore, the slots influence the direction of current flow within the contact element and thus also the magnetic field generated by this current flow. Therefore, the magnetic field can be specifically controlled by a suitable arrangement and orientation of the slots.

[0019] In one embodiment of a contact element according to the invention, at least one slot in the contact shaft t lies in a plane that is perpendicular to the end face of the contact shaft ts. This advantageously reduces or prevents eddy currents that run around the longitudinal axis of the contact shaft t, and the current in the contact shaft t is guided substantially parallel to the longitudinal axis.

[0020] In a further embodiment of a contact element according to the invention, at least one slot extends in the pot base at least between an edge of the pot base and the base region. This advantageously reduces or prevents eddy currents that flow around the longitudinal axis of the contact shaft in the pot base, and the current in the pot base is essentially guided between the base region connected to the contact shaft and the edge of the pot base.

[0021] In a further embodiment of a contact element according to the invention, each end of each slot cuts into the edge of the pot base. In other words, at least one slot divides the pot base into two sections between which no current can flow.

[0022] In a further embodiment of a contact element according to the invention, at least one slot extends in the pot wall between the pot base and the contact disc. (2024PF00924)

[0023] 4

[0024] The current is guided through such a slot in the pot wall between the pot bottom and the contact disc.

[0025] In a further embodiment of a contact element according to the invention, at least one slot in the pot wall extends along a curve whose orthogonal projection onto a plane orthogonal to a longitudinal axis of the contact shaft is curved. For example, at least one slot in the pot wall extends along a curve whose orthogonal projection onto a plane orthogonal to a longitudinal axis of the contact shaft has a curvature of constant sign. In particular, if the slot in the pot wall extends between the pot base and the contact disc, this means that the slot in the pot wall essentially lies in a plane that is slightly tilted relative to a plane orthogonal to a longitudinal axis of the contact shaft. Therefore, a current is guided through the slot in the pot wall essentially along a circular arc around the longitudinal axis of the contact shaft.If both contact elements of a vacuum interrupter are designed in this way, the current paths in the cup walls of the contact elements can generate a magnetic field similar to that of a Heimholt coil, which is largely homogeneous and axially aligned between the contact elements, i.e., in the direction of the longitudinal axes of the contact shafts. This advantageously enables a largely uniform distribution of a metal vapor arc between the contact elements.

[0026] In a further embodiment of a contact element according to the invention, at least one slot in the pot base is connected to a slot in the contact shaft t and / or to a slot in the pot wall. This allows currents to be conducted directly between the pot base and the contact shaft t and / or the pot wall.

[0027] In a further embodiment of a contact element according to the invention, at least one slot in the contact shaft t is filled with a material that has a lower 2024PF00924

[0028] 5

[0029] The contact element has a lower electrical conductivity than the contact shaft. Accordingly, in a further embodiment of a contact element according to the invention, at least one slot in the pot base and / or at least one slot in the pot wall is filled with a material that has a lower electrical conductivity than the contact pot. Such filling of slots in the contact shaft, the pot base and / or the pot wall can advantageously increase the stability of the contact element without impairing the function of the slots.

[0030] In a further embodiment of a contact element according to the invention, the contact disc has at least one slot. This allows the magnetic field and the current flow in the contact disc to be influenced by slots in the contact disc.

[0031] In a further embodiment of a contact element according to the invention, at least one slot in the contact disc has a first end that slots an edge of the contact disc and a second end that does not slot the edge of the contact disc. In other words, at least one slot extends from the edge of the contact disc to a point on the contact disc that is not located on its edge.

[0032] In a further embodiment of a contact element according to the invention, at least one slot in the contact disc is connected to a slot in the pot wall. This allows currents to be conducted directly between the pot wall and the contact disc.

[0033] In a further embodiment of a contact element according to the invention, at least one slot in the contact disc is filled with a material that has a lower electrical conductivity than the contact disc. This also increases the stability of the contact element. 2024PF00924

[0034] A vacuum switching tube according to the invention comprises at least one contact element according to the invention. The advantages of a vacuum switching tube according to the invention result from the advantages of a contact element according to the invention mentioned above.

[0035] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more readily understandable in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the drawings. These drawings show:

[0036] FIG 1 shows a perspective view of an embodiment of a contact element of a

[0037] Vacuum switching tube,

[0038] FIG 2 is a transparent perspective view of the contact element shown in Figure 1,

[0039] FIG 3 shows a sectional view of the contact element shown in Figure 1 ,

[0040] FIG 4 shows a top view of a contact disk of a contact element of a vacuum switching tube,

[0041] FIG 5 schematically shows a sectional view of an embodiment of a vacuum switching tube.

[0042] Corresponding parts are marked with the same reference symbols in the figures.

[0043] Figures 1 to 3 show an embodiment of a contact element 1 of a vacuum switching tube according to the invention. Figure 1 (FIG 1) shows a perspective view of the contact element 1. Figure 2 (FIG 2) shows a transparent perspective view of the contact element 1. Figure 3 (FIG 3) shows a sectional view of the contact element 1. 2024PF00924

[0044] The contact element 1 comprises an electrically conductive contact shaft t 3, an electrically conductive contact pot 5 and an electrically conductive contact disc 6.

[0045] The contact shaft t 3 is column-shaped and has an end face 7 connected to the contact cup 5, which is perpendicular to a longitudinal axis 8 of the contact shaft t 3. An end region 9 of the contact shaft t 3, encompassing the end face 7, has three slots 11. Each slot 11 lies in a plane 13 that is perpendicular to the end face 7 and in which the longitudinal axis 8 of the contact shaft t 3 runs. The longitudinal axis 8 is thus the line of intersection of the three planes 13. The planes 13 each have an angle of 120 degrees to each other. Each slot 11 extends over the entire diameter of the contact shaft t 3.

[0046] The contact pot 5 is pot-shaped with a pot base 15 and a pot wall 17 projecting from the pot base 15. The pot base 15 has a base area 19 against which the end face 7 of the contact shaft 3 abuts and to which the end face 7 is connected. The pot base 15 has three slots 21. Each slot 21 is connected to a slot 11, lies in the same plane 13 as this slot 11, and extends over the entire width of the pot base 15, so that each end of the slot 21 slits an edge 23 of the pot base 15.

[0047] The pot wall 17 has six slots 25. Each slot 25 runs between the pot base 15 and the contact disk 6 along a curve that essentially lies in a plane slightly tilted relative to a plane orthogonal to the longitudinal axis 8, such that the orthogonal projection of the curve onto the plane orthogonal to the longitudinal axis 8 has a curvature of constant sign. Each slot 25 is connected to a slot 21.

[0048] 8

[0049] The contact disc 6 covers the contact pot 5 and is connected to the pot wall 17. The contact disc 6 has six slots 27. Each slot 27 is connected to a slot 25.

[0050] Figure 4 (FIG 4) shows a top view of the contact disk 6. Each slot 27 has a first end 29 that slots a circular rim 31 of the contact disk 6, and a second end 30 that does not slot the rim 31 of the contact disk 6. Each slot 27 extends along a chord of the circle defined by the rim 31 of the contact disk 6, with this chord not passing through the center of the circle. The slots 27 do not intersect each other.

[0051] The embodiment of a contact element 1 shown in Figures 1 to 4 can be modified in various ways to form other embodiments. For example, the contact shaft t 3, the pot base 15, the pot wall 17, and / or the contact disc 6 can each have a different number of slots 11, 21, 25, and 27, respectively. Furthermore, the slots 11, 21, 25, and 27 can have different orientations. For example, the slots 21 can each extend only between the edge 23 of the pot base 15 and the contact shaft t 3, and the slots 21, similar to the slots 27 in Figure 4 in the contact disc 6, can also extend obliquely instead of radially in the pot base 15, so that the slots 21 no longer lie in each of the planes 13. The slots 11 do not necessarily have to extend over the entire diameter of the contact shaft ts 3, but can extend only over a part of the diameter of the contact shaft ts 3.The slots 11 and / or the slots 21 can also be located in planes that are not perpendicular to the end face 7, but are, for example, each slightly tilted relative to a plane 13. The slots 27 can, for example, also run radially instead of obliquely in the contact disc 6. Furthermore, the slots 11 do not necessarily each have to correspond to one of the slots 212024PF00924.

[0052] 9

[0053] The slots 21 do not necessarily have to be connected to each of the slots 25, and the slots 25 do not necessarily have to be connected to each of the slots 27.

[0054] At least one slot 11 can furthermore be filled with a material that has a lower electrical conductivity than the contact shaft 3. Similarly, at least one slot 21 and / or at least one slot 25 can be filled with a material that has a lower electrical conductivity than the contact cup 5, and / or at least one slot 27 can be filled with a material that has a lower electrical conductivity than the contact disc 6.

[0055] Figure 5 (FIG 5) schematically shows a sectional view of an embodiment of a vacuum switching tube 40 according to the invention. The vacuum switching tube 40 comprises a housing 41 and two contact elements 1, each configured like the contact element 1 shown in Figures 1 to 4 or a modification of this contact element 1 described above. The section plane of Figure 5 passes through the housing 41 in front of the contact elements 1. The slots 11, 21, 25, 27 of the contact elements 1 are not shown in Figure 5. The housing 41 is shown only schematically in Figure 5. For example, the housing 41 can have one or more insulating bodies (not shown in Figure 5), each forming a section of the housing 41. Furthermore, the vacuum switching tube 40 can have a bellows that surrounds a section of a contact shaft ts 3 movable relative to the housing 41 and is connected gas-tight to the housing 41 and to this contact shaft t 3 j respectively.

[0056] The contact elements 1 are arranged such that their contact discs 6 face each other inside the housing 41 and touch each other in a first switching position of the contact elements 1 and in a position shown in Figure 52024PF00924

[0057] 10

[0058] The second switching position shown is separated from each other. The contact shafts 3 of the contact elements 1 are brought out of the housing 41. At least one contact shaft 3 is movable relative to the housing 41.

[0059] Although the invention has been further illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples and other variations can be derived from them by a person skilled in the art without leaving the scope of protection of the invention.

Claims

2024PF00924 11 Patent claims 1. Contact element ( 1 ) of a vacuum switching tube ( 40 ) comprising the contact element ( 1 ) - an electrically conductive column-like Contact t ( 3 ) , - an electrically conductive contact pot ( 5 ) with a pot base ( 15 ) and a pot wall ( 17 ) projecting from the pot base ( 15 ), wherein the pot base ( 15 ) has a base area ( 19 ) which is connected to an end face ( 7 ) of the contact shaft ( 3 ), and - an electrically conductive contact disc ( 6 ) which covers the contact pot ( 5 ) and is connected to the pot wall ( 17 ) wherein - an end region (9) of the contact shaft (3) encompassing the end face (7), the pot base (15) and the pot wall (17) each having at least one slot (11, 21, 25).

2. Contact element (1) according to claim 1, wherein at least one slot (11) in the contact shaft (3) lies in a plane (13) which is perpendicular to the end face (7) of the contact shaft (3).

3. Contact element (1) according to claim 1 or 2, wherein at least one slot (21) in the pot base (15) extends at least between an edge (23) of the pot base (15) and the base area (19).

4. Contact element ( 1 ) according to one of the preceding claims, wherein each end of each slot ( 21 ) in the pot base ( 15 ) slots the edge ( 23 ) of the pot base ( 15 ).

5. Contact element (1) according to one of the preceding claims, wherein at least one slot (25) extends in the pot wall (17) between the pot base (15) and the contact disc (6). 2024PF00924 12 6. Contact element ( 1 ) according to one of the preceding claims, wherein at least one slot ( 25 ) in the pot wall ( 17 ) extends along a curve whose orthogonal projection is curved onto a plane orthogonal to a longitudinal axis ( 8 ) of the contact shaft ( 3 ).

7. Contact element (1) according to one of the preceding claims, wherein at least one slot (25) in the pot wall (17) extends along a curve whose orthogonal projection onto a plane orthogonal to a longitudinal axis (8) of the contact shaft (3) has a curvature of constant sign.

8. Contact element (1) according to one of the preceding claims, wherein at least one slot (21) in the pot base (15) is connected to a slot (11) in the contact shaft ( 3 ) and / or is connected to a slot ( 25 ) in the pot wall ( 17 ).

9. Contact element (1) according to one of the preceding claims, wherein at least one slot (11) in the contact shaft t (3) is filled with a material having a lower electrical conductivity than the contact shaft t (3).

10. Contact element (1) according to one of the preceding claims, wherein at least one slot (21) in the pot base (15) and / or at least one slot (25) in the pot wall (17) is filled with a material which has a lower electrical conductivity than the contact pot (5).

11. Contact element ( 1 ) according to one of the preceding claims, wherein the contact disc ( 6 ) has at least one slot ( 27 ).

12. Contact element (1) according to claim 11, wherein at least one slot (27) in the contact disc (6) forms a first end (29), 2024PF00924 13 which has one edge (31) of the contact disc (6) slit, and a second end (30) which does not slit the edge (31) of the contact disc (6).

13. Contact element ( 1 ) according to claim 11 or 12, wherein at least one slot ( 27 ) in the contact disc ( 6 ) is connected to a slot ( 25 ) in the pot wall ( 17 ).

14. Contact element ( 1 ) according to one of claims 11 to 13, wherein at least one slot ( 27 ) in the contact disc ( 6 ) is filled with a material which has a lower electrical conductivity than the contact disc ( 6 ).

15. Vacuum switching tube ( 40 ) with at least one contact element ( 1 ) designed according to one of the preceding claims .

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