CN118098871A - Vacuum arc-extinguishing chamber and vacuum switch - Google Patents

Abstract

The application discloses a vacuum arc-extinguishing chamber and a vacuum switch, wherein the vacuum arc-extinguishing chamber comprises: the insulation shell is respectively arranged on the fixed contact and the movable contact in the insulation shell and is fixed on the main shielding cover in the insulation shell; the main shielding cover comprises a coil closed loop, the coil closed loop comprises a spiral coil, and the spiral coil surrounds a movable contact end of the movable contact and a static contact end of the static contact; the fixed contact and the moving contact are sequentially distributed along the axial direction of the spiral coil; under the condition that short-circuit current flows through the vacuum arc extinguishing chamber, the spiral coil generates induction current, the induction current flows through the spiral coil to generate an induction magnetic field, and the induction magnetic field is a longitudinal magnetic field. Therefore, the main shielding cover can generate a required longitudinal magnetic field, based on the fact that special structural design is not needed for the moving contact and the fixed contact, the structures of the moving contact and the fixed contact can be simplified, for example, the moving contact and the fixed contact are selected to be flat contact structures, the through-flow capacity of the vacuum arc-extinguishing chamber is improved, and the vacuum arc-extinguishing chamber is convenient to use at a high voltage level.

Description

Vacuum arc-extinguishing chamber and vacuum switch

Technical Field

The application relates to the technical field of vacuum switches, in particular to a vacuum arc extinguishing chamber and a vacuum switch.

Background

The vacuum switch uses the vacuum arc-extinguishing chamber as an arc-extinguishing device, and when the short-circuit current occurs, the vacuum arc-extinguishing chamber cuts off the short-circuit current through the excellent insulativity of vacuum in the pipe, so that accidents and accidents are avoided. For a vacuum switch and a vacuum arc-extinguishing chamber, in the process of breaking and short-circuiting current, a longitudinal magnetic field is applied between a moving contact and a fixed contact of the vacuum arc-extinguishing chamber to keep a vacuum arc in a diffusion state, so that the vacuum arc-extinguishing chamber is an important means for improving breaking capacity.

At present, a common method for applying a longitudinal magnetic field between a moving contact and a fixed contact of a vacuum arc-extinguishing chamber is to specially design the moving contact and the fixed contact of the vacuum arc-extinguishing chamber, so that a short circuit current generates the longitudinal magnetic field when flowing on the contacts according to a designed path. Therefore, the structure of the guide actuating and static contact is complex, the contact resistance is larger, the heat generation amount is more, the temperature rise of the vacuum arc-extinguishing chamber is higher, the current passing capability of the vacuum arc-extinguishing chamber is limited, and the use of the vacuum arc-extinguishing chamber at a high voltage level is limited.

In summary, how to improve the current capacity of the vacuum arc-extinguishing chamber based on the application of the longitudinal magnetic field in the switching-on and switching-off process, so as to facilitate the use of the vacuum arc-extinguishing chamber at a high voltage level, is a problem to be solved by those skilled in the art.

Disclosure of Invention

Therefore, the application aims to provide the vacuum arc-extinguishing chamber and the vacuum switch, which can improve the current capacity of the vacuum arc-extinguishing chamber on the basis of applying a longitudinal magnetic field in the switching-on and switching-off process, and facilitate the use of the vacuum arc-extinguishing chamber at a high voltage level.

In order to achieve the above purpose, the present application provides the following technical solutions:

A vacuum interrupter, comprising: the insulation shell is respectively arranged on the fixed contact and the movable contact in the insulation shell and is fixed on the main shielding cover in the insulation shell;

The main shielding cover comprises a coil closed loop, wherein the coil closed loop comprises a spiral coil, and the spiral coil surrounds a movable contact end of the movable contact and a static contact end of the static contact; the fixed contact and the moving contact are sequentially distributed along the axial direction of the spiral coil; under the condition that short-circuit current flows through the vacuum arc-extinguishing chamber, the spiral coil generates induction current, and the induction current flowing through the spiral coil generates an induction magnetic field which is a longitudinal magnetic field.

Optionally, the spiral coil is at least two and overlaps in proper order and establishes, and all spiral coil is in proper order the head and the tail electricity is connected, and arbitrary two spiral coil's spiral direction is the same.

Optionally, the two adjacent spiral coils are respectively an inner coil and an outer coil; in the axial direction of the spiral coil, the inner layer coil and the outer layer coil are arranged in a staggered mode, so that the outer layer coil shields gaps between two adjacent coils in the inner layer coil.

Optionally, any two spiral coils are coaxially arranged.

Optionally, two adjacent spiral coils are electrically connected through a connecting wire.

Optionally, among all the spiral coils, the spiral coil located at the outermost layer is fixed on the insulating housing, and the spiral coil located at the outermost layer and the spiral coil located at the innermost layer are fixedly connected through a connecting plate.

Optionally, the connecting plates are disposed at two ends of the spiral coil, the connecting plates are annular, and the connecting plates cover all the spiral coils.

Optionally, the outer surface of the connecting plate far away from the spiral coil is a smooth curved surface, and the smooth curved surface protrudes towards one end far away from the spiral coil.

Optionally, in all the spiral coils, the spiral coil located at the outermost layer is welded to the insulating housing through a sealing ring, and the spiral coil located at the outermost layer and the spiral coil located at the innermost layer are both welded and connected with the connecting plate.

Based on the vacuum arc-extinguishing chamber provided by the application, the application also provides a vacuum switch, which comprises the vacuum arc-extinguishing chamber.

According to the vacuum arc extinguishing chamber provided by the application, under the condition that short-circuit current occurs, the moving contact is separated from the fixed contact, and vacuum arc is generated in the separation process; the short-circuit current flows through the fixed contact, the vacuum arc and the moving contact in sequence, namely, the short-circuit current passes through the hollow area of the spiral coil, the spiral coil generates induction current based on the law of electromagnetic induction and Lenz's law, the direction of the induction current is opposite to the direction of the short-circuit current, the direction of the induction current is vertical downward as an example, the direction of the induction current is vertical upward, the induction current flows through the spiral coil because the induction current needs to take the spiral coil as a carrier, the induction current flows through the spiral coil to generate an induction magnetic field, the induction magnetic field generated by the induction current flowing through the spiral coil is a longitudinal magnetic field based on the right-hand rule, the longitudinal magnetic field acts on the vacuum arc between the moving contact and the fixed contact, the vacuum arc shape is controlled, and the breaking capacity is improved. Therefore, under the condition of short-circuit current, the main shielding cover can generate a required longitudinal magnetic field, based on the fact, the moving contact and the fixed contact do not need to be specially designed, the structures of the moving contact and the fixed contact can be simplified, for example, the moving contact and the fixed contact are selected to be flat contact structures, the current passing capability of the vacuum arc-extinguishing chamber is improved, and the vacuum arc-extinguishing chamber is convenient to use at a high voltage level.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a vacuum arc extinguishing chamber according to an embodiment of the present application;

Fig. 2 is an isometric view of a part of a main shield in a vacuum interrupter according to an embodiment of the application;

FIG. 3 is a top view of the structure shown in FIG. 2;

fig. 4 is an isometric view of a main shield in a vacuum interrupter provided by an embodiment of the application;

fig. 5 is a schematic diagram of a longitudinal magnetic field when a vacuum interrupter according to an embodiment of the present application flows through a short circuit current.

Reference numerals illustrate:

1 is a main shielding cover, 11 is a spiral coil, 11a is an inner coil, 11b is an outer coil, 12 is a connecting wire, and 13 is a connecting plate; 2 is a closed ring, 3 is an insulating shell, 4 is a static contact, 41 is a static contact end, 5 is a moving contact, 51 is a moving contact end, 52 is a moving contact support, and 6 is a corrugated pipe.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. The terminology used in the following examples is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the specification of the application and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include, for example, "one or more" such forms of expression, unless the context clearly indicates to the contrary. It should also be understood that in embodiments of the present application, "one or more" means one, two, or more than two; "and/or", describes an association relationship of the association object, indicating that three relationships may exist; for example, a and/or B may represent: a alone, a and B together, and B alone, wherein A, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship.

Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

"Parallel" as referred to in the present application is "substantially parallel" in actual operation. "substantially parallel" is understood to mean parallel with some error.

In the vacuum arc-extinguishing chamber, after short-circuit current occurs, the moving contact is separated from the fixed contact, and vacuum arc is generated in the separation process, and the vacuum arc influences the current-breaking capacity and the service life of the vacuum arc-extinguishing chamber.

At present, by designing the contact structure of the vacuum arc-extinguishing chamber, for example, the contact is in a cup-shaped longitudinal magnetic structure, a coil-shaped longitudinal magnetic structure and the like so as to generate a longitudinal magnetic field during arcing, the longitudinal magnetic field can uniformly distribute vacuum arcs on the surface of the contact, low vacuum arc voltage is maintained, and the vacuum arcs are uniformly distributed on the surface of the contact, so that the vacuum arc-extinguishing chamber has higher medium strength recovery speed after arcing. Thus, the current breaking capacity and service life of the vacuum arc-extinguishing chamber are improved.

The design leads to the contact structure complicated, and contact resistance is great, and the heat generation quantity is more for the temperature rise of vacuum interrupter is higher, has restricted vacuum interrupter's through-flow ability, makes vacuum interrupter's use limited at high voltage class.

Based on the problems, the embodiment of the application provides the vacuum arc-extinguishing chamber, which can simplify the contact structure of the vacuum arc-extinguishing chamber on the basis of applying a longitudinal magnetic field in the switching-on and switching-off process, can improve the current capacity of the vacuum arc-extinguishing chamber and is convenient for the use of the vacuum arc-extinguishing chamber at a high voltage level.

As shown in fig. 1, the vacuum interrupter includes: an insulating shell 3, a fixed contact 4, a moving contact 5 and a main shielding cover 1.

The insulating housing 3 may be a porcelain shell or other material, which is not limited in this embodiment.

The stationary contact 4 is disposed in the insulating housing 3. In order to ensure the stability of the stationary contact 4, it is optional that the stationary contact 4 is fixed in the insulating housing 3. The stationary contact 4 includes a stationary contact end 41 and a stationary contact leg that are electrically connected.

The movable contact 5 is disposed in the insulating housing 3. In order to ensure that the moving contact 5 moves to achieve contact and separation of the moving contact 5 and the stationary contact 4, the moving contact 5 may be optionally movably disposed within the insulating housing 3. The moving contact 5 includes a moving contact end 51 and a moving contact leg 52 electrically connected. The moving contact column 52 of the moving contact 5 is sleeved with a corrugated tube 6, the corrugated tube 6 is positioned in the insulating shell 3, and the corrugated tube 6 is used for generating a vacuum cavity environment.

The main shield 1 is fixed within an insulating housing 3. The main shield 1 encloses the movable contact end 51 of the movable contact 5 and the stationary contact end 41 of the stationary contact 4. The main shield 1 serves to prevent the vacuum arc plasma from eroding the insulating housing 3 during arcing, thereby avoiding a decrease in the along-surface insulating ability of the main shield 1.

The main shield 1 comprises a coil closed loop comprising a spiral coil 11, which spiral coil 11 encloses a moving contact end 51 of the moving contact 5 and a stationary contact end 41 of the stationary contact 4.

The fixed contact 4 and the moving contact 5 are distributed in sequence along the axial direction of the spiral coil 11, and the moving contact 5 is movably arranged on the insulating housing 3 along the axial direction of the spiral coil 11.

The number of the spiral coil 11 may be one or two or more. In the case of one spiral coil 11, the end-to-end electrical connection of the spiral coil 11 may be selected to form a closed loop of the coil. In the case that the number of the spiral coils 11 is more than two, that is, all the spiral coils 11 are sequentially sleeved, the spiral directions of any two spiral coils 11 are the same, and all the spiral coils 11 are sequentially electrically connected end to form a coil closed loop.

Illustratively, as shown in fig. 2 and 3, the spiral coils 11 are two, one spiral coil 11 is an inner layer coil 11a, and the other spiral coil 11 is an outer layer coil 11b.

As shown in fig. 5, in the vacuum arc extinguishing chamber provided in the above embodiment, under the condition that a short circuit current occurs, the moving contact 5 is separated from the fixed contact 4, and a vacuum arc is generated in the separation process; the short-circuit current flows through the fixed contact 4, the vacuum arc and the moving contact 5 in sequence, namely, the short-circuit current passes through the hollow area of the spiral coil 11, and because the short-circuit current suddenly increases, the spiral coil 11 generates an induction current based on the law of electromagnetic induction and Lenz's law, the direction of the induction current is opposite to that of the short-circuit current, taking the vertical downward direction as an example, the direction of the induction current is vertical upward, and because the induction current needs to take the spiral coil 11 as a carrier, the induction current flows through the spiral coil 11, and the induction current flows through the spiral coil 11 to generate an induction magnetic field, and based on the right-hand rule, the induction magnetic field generated by the induction current flowing through the spiral coil 11 is a longitudinal magnetic field.

As shown in fig. 5, the spiral coil 11 is a right-handed coil, the direction of the short-circuit current is vertically downward, the direction of the induced current is vertically upward, the induced current flows through the spiral coil 11 in a clockwise direction, and the direction of the induced magnetic field generated by the induced current flowing through the spiral coil 11 is vertically downward as known from the right-handed rule.

If the right-handed coil shown in fig. 5 is changed to the left-handed coil, the induced current flows through the spiral coil 11 in the counterclockwise direction, and the direction of the induced magnetic field generated by the induced current flowing through the spiral coil 11 is vertically upward as known from the right-handed rule.

The term "clockwise" in the above description refers to a clockwise direction when facing the paper surface on which fig. 5 is shown. The term "counterclockwise" in the above text refers to a counterclockwise direction in the case of facing the paper surface on which fig. 5 is located.

The vacuum arc pattern can be controlled by the induced magnetic field generated by the induced current flowing through the spiral coil 11, either vertically upwards or vertically downwards.

As is clear from the above, in the case where the short-circuit current flows through the vacuum interrupter, the spiral coil 11 generates an induced current, and the induced current flows through the spiral coil 11 to generate an induced magnetic field, and the induced magnetic field is a longitudinal magnetic field, and the longitudinal magnetic field acts on the vacuum arc between the moving contact 5 and the fixed contact 4 to control the vacuum arc shape, thereby being beneficial to improving the breaking capability. Therefore, under the condition of short-circuit current, the main shielding cover 1 can generate a required longitudinal magnetic field, based on the fact that the movable contact 5 and the fixed contact 4 do not need to be specially designed, the structures of the movable contact 5 and the fixed contact 4 can be simplified, for example, the movable contact 5 and the fixed contact 4 are selected to be flat-plate contact structures, the through-flow capacity of the vacuum arc extinguishing chamber is improved, and the vacuum arc extinguishing chamber is convenient to use at a high voltage level.

It should be noted that the spiral coil 11 surrounds the moving contact end 51 and the fixed contact end 41, so that the longitudinal magnetic field generated in the hollow area of the spiral coil 11 can be applied to the gap area between the fixed contact 4 and the moving contact 5. The spiral coil 11 has the effect of blocking the vacuum arc plasma from eroding the insulating envelope 3. In the vacuum interrupter, the larger the short-circuit current is, the larger the longitudinal magnetic field of the hollow area of the spiral coil 11 is, and the better the vacuum arc control effect is.

In the vacuum arc extinguishing chamber provided by the embodiment of the application, the spiral coil 11 surrounds the movable contact end 51 of the movable contact 5 and the static contact end 41 of the static contact 4, the static contact 4 and the movable contact 5 are sequentially distributed along the axial direction of the spiral coil 11, and the movable contact 5 is movably arranged on the insulating shell 3 along the axial direction of the spiral coil 11, so that the spiral coil 11 is not connected with the movable contact 5, the spiral coil 11 is not connected with the static contact 4, the movement of the movable contact 5 is prevented from influencing the action of the spiral coil 11, the reliability of generating a longitudinal magnet is improved, and the switching-on and switching-off capability is further facilitated.

Meanwhile, in the vacuum arc-extinguishing chamber provided by the embodiment of the application, the axial direction of the spiral coil 11 is the moving direction of the moving contact 5, so that the number of turns (turns) of the spiral coil 11 is regulated according to the requirement, thereby regulating the intensity of a longitudinal magnetic field generated in a hollow area of the spiral coil 11 and improving the adaptability of the vacuum arc-extinguishing chamber to the voltages at two ends of the vacuum arc-extinguishing chamber.

In the vacuum arc extinguishing chamber provided by the embodiment of the application, the longitudinal magnetic field intensity generated by the hollow area of the spiral coil 11 can be regulated by changing the material of the spiral coil 11.

The vacuum arc-extinguishing chamber can generate a longitudinal magnetic field only under the condition that short-circuit current flows between the moving contact and the fixed contact, and no longitudinal magnetic field is generated after the current is cut off, so that the recovery of a medium after an arc is facilitated, and the cut-off success rate is improved.

In the vacuum interrupter, two adjacent spiral coils 11 are an inner coil 11a and an outer coil 11b; in the axial direction of the spiral coil 11, the inner layer coil 11a and the outer layer coil 11b are arranged in a staggered manner so that the outer layer coil 11b shields the gap between two adjacent turns in the inner layer coil 11 a. In this way, the barrier effect of the main shield 1 against vacuum arc plasma is improved.

In some embodiments, in a case where the moving contact 5 and the fixed contact 4 are separated, a gap between the moving contact 5 and the fixed contact 4 is located at the middle in the axial direction of the main shield 1. Thus, the control effect of the longitudinal magnetic field on the vacuum arc shape is improved, and the blocking effect of the main shielding cover 1 on the vacuum arc plasma is also improved.

In other embodiments, in the case where the moving contact 5 and the fixed contact 4 are separated, the gap between the moving contact 5 and the fixed contact 4 may be closer to the end of the main shield 1 than the middle of the main shield 1.

In the vacuum interrupter, any two spiral coils 11 are coaxially arranged, or at least the axes of two spiral coils 11 are parallel. Any two spiral coils 11 can be selected to be coaxially arranged in order to improve the longitudinal magnetic field strength.

In the vacuum interrupter, as shown in fig. 1 to 3, two adjacent spiral coils 11 are electrically connected by a connecting wire 12. Illustratively, the inner layer coil 11a and the outer layer coil 11b are electrically connected by a connection wire 12.

As for the shape, size and distribution of the connection lines 12, the connection lines 12 are selected according to practical situations, and exemplary connection lines 12 are semicircular or U-shaped, which is not limited in the embodiment of the present application.

In the vacuum interrupter, the main shield 1 is fixed to the insulating case 3. As shown in fig. 1, 4 and 5, in some embodiments, among all the spiral coils 11, the spiral coil 11 located at the outermost layer is fixed to the insulating housing 3, and the spiral coil 11 located at the outermost layer and the spiral coil 11 located at the innermost layer are fixedly connected by a connection plate 13.

For facilitating the fixed connection, the spiral coil 11 positioned on the outermost layer can be welded on the insulating shell 3 through the sealing ring 2; the spiral coil 11 positioned at the outermost layer and the spiral coil 11 positioned at the innermost layer are welded and connected with the connecting plate 13.

Of course, the spiral coil 11 located at the outermost layer may be fixed to the insulating housing 3 by other means, the spiral coil 11 located at the outermost layer and the connection plate 13 may be fixedly connected by other means, and the spiral coil 11 located at the innermost layer and the connection plate 13 may be fixedly connected by other means, which is not limited in the embodiment of the present application.

In some embodiments, the connection plates 13 are disposed at least one end of the spiral coil 11, and in order to improve the stability of the main shield 1, the connection plates 13 may be optionally disposed at both ends of the spiral coil 11.

In other embodiments, the connection plate 13 is annular, thus improving the connection area and connection strength of the connection plate 13 and improving the stability of the entire main shield 1. In order to facilitate the fixed connection between the spiral coil 11 located at the outermost layer and the spiral coil 11 located at the innermost layer through the connection plate 13, the connection plate 13 may be selected to cover all the spiral coils 11.

In some embodiments, the connection plates 13 may be optionally disposed at two ends of the spiral coil 11, the connection plates 13 are annular, and the connection plates 13 cover all the spiral coils 11. Based on this, the outer surface of the connection plate 13 remote from the spiral coil 11 is a smooth curved surface that protrudes toward the end remote from the spiral coil 11. In this way, the connecting plate 13 has a shielding effect, reduces the maximum electric field value at two ends of the main shielding cover 1, and improves the voltage-resisting capability and the breaking reliability of the vacuum arc extinguishing chamber.

It should be noted that the connection plate 13 is a metal plate or other conductive plate, which is not limited in the embodiment of the present application.

For ease of production and manufacture, the outer surface of the connection plate 13 remote from the spiral coil 11 may be selected to be a cambered surface. In this case, the whole connection plate 13 may be selected to be an arc plate. Illustratively, among all the spiral coils 11, the spiral coil 11 located at the outermost layer is fixedly connected with the outer end of the connection plate 13, the spiral coil 11 located at the innermost layer is fixedly connected with the inner end of the connection plate 13, the connection plate 13 has an arc-shaped structure from the inner end to the outer end thereof, and the arc-shaped structure protrudes toward the end far from the spiral coil 11.

Based on the vacuum arc-extinguishing chamber provided by the embodiment, the embodiment of the application also provides a vacuum switch, which comprises the vacuum arc-extinguishing chamber provided by the embodiment.

For the specific type of vacuum switch, it is chosen according to the actual situation. Illustratively, the vacuum switch is a vacuum circuit breaker, which is mainly used for substations and grid facilities in the power sector, or a vacuum load switch, which is mainly used for end users of the grid.

Because the vacuum interrupter provided by the above embodiment has the above technical effects, the vacuum switch provided by the above embodiment includes the above vacuum interrupter, and the vacuum switch provided by the above embodiment also has corresponding technical effects, which are not described herein again.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A vacuum interrupter, comprising: the insulation shell is respectively arranged on the fixed contact and the movable contact in the insulation shell and is fixed on the main shielding cover in the insulation shell;

The main shielding cover comprises a coil closed loop, wherein the coil closed loop comprises a spiral coil, and the spiral coil surrounds a movable contact end of the movable contact and a static contact end of the static contact; the fixed contact and the moving contact are sequentially distributed along the axial direction of the spiral coil; under the condition that short-circuit current flows through the vacuum arc-extinguishing chamber, the spiral coil generates induction current, the induction current flows through the spiral coil to generate an induction magnetic field, and the induction magnetic field is a longitudinal magnetic field.

2. The vacuum interrupter of claim 1, wherein at least two spiral coils are sleeved in sequence, all the spiral coils are electrically connected in sequence end to end, and spiral directions of any two spiral coils are the same.

3. The vacuum interrupter of claim 2, wherein adjacent two of the spiral coils are an inner coil and an outer coil, respectively; in the axial direction of the spiral coil, the inner layer coil and the outer layer coil are arranged in a staggered mode, so that the outer layer coil shields gaps between two adjacent coils in the inner layer coil.

4. A vacuum interrupter according to claim 2, wherein any two of the spiral coils are coaxially disposed.

5. The vacuum interrupter of claim 2, wherein adjacent two of the spiral coils are electrically connected by a connecting wire.

6. The vacuum interrupter of claim 2, wherein among all the spiral coils, the outermost spiral coil is fixed to the insulating case, and the outermost spiral coil and the innermost spiral coil are fixedly connected by a connection plate.

7. The vacuum interrupter of claim 6, wherein the connection plates are disposed at both ends of the spiral coil, the connection plates are ring-shaped, and the connection plates cover all of the spiral coil.

8. The vacuum interrupter of claim 7, wherein an outer surface of the connecting plate remote from the spiral coil is a smooth curved surface, and the smooth curved surface protrudes toward an end remote from the spiral coil.

9. The vacuum interrupter of claim 6, wherein among all the spiral coils, the spiral coil located at the outermost layer is welded to the insulating case by a sealing ring, and the spiral coil located at the outermost layer and the spiral coil located at the innermost layer are both welded to the connection plate.

10. A vacuum switch comprising a vacuum interrupter as claimed in any one of claims 1-9.