Contact structure of vacuum arc-extinguishing chamber of high-capacity circuit breaker

Abstract

According to the contact structure of the vacuum arc-extinguishing chamber of the high-capacity circuit breaker, in the contact structure of the vacuum arc-extinguishing chamber of the high-capacity circuit breaker, a plurality of open grooves extend from the edge of a contact blade body to the direction close to the center of the contact blade body so as to increase a magnetic field and reduce eddy current, and a plurality of blocking grooves are formed between every two adjacent open grooves so as to block contact arc movement. The projection of the open groove is formed by vertically projecting the open groove on the other contact blade body relative to the contact blade body onto the contact blade body, and the projection of the open groove is at least partially overlapped with the open groove and at least partially overlapped with the blocking groove.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum interrupter chambers, in particular to a contact structure of a vacuum interrupter chamber of a large-capacity circuit breaker. Background Art

[0002] The vacuum circuit breaker is a key equipment for cutting off the safety of the fault protection system, and it also has the advantage of being environmentally friendly. Among them, the vacuum interrupter is its key core component and bears the important responsibilities of breaking, extinguishing arcs and bearing pressure. In recent years, with the rapid growth of my country's economic construction, the demand for electricity has become more vigorous, and the capacity of generator sets has increased year by year, resulting in an increase in short-circuit currents. This requires the vacuum interrupter to have a stronger breaking capacity. However, when breaking a large current, the large-diameter contact will generate multiple arc starting points at different positions in the small contact gap in the initial stage of the opening, and then develop into multiple stable arc columns. These arc columns will move rapidly as the contact opening distance increases, and eventually converge together to become an arc column. The current density of the arc column rises sharply and burns stably. Due to the large current, the concentrated arc column is difficult to spread, resulting in severe ablation of a certain point of the contact, greatly reducing the utilization rate of the contact space and greatly reducing the breaking capacity.

[0003] The traditional contact slot is an extension of the contact cup slot, which reduces the eddy current of the contact and provides a certain magnetic field. The arc will be hindered to a certain extent at the cross-border slot, resulting in a slower movement speed. However, the conventional contact slots all point to the center of the contact, causing multiple arcs to move quickly along the slot direction to the center of the contact to converge, which is not conducive to breaking.

[0004] The information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0005] In view of the shortcomings or defects of the prior art, a large-capacity circuit breaker vacuum interrupter contact structure is provided, which effectively slows down the convergence speed of multiple arc columns, makes multiple arc columns exist in the contact gap for a long time, reduces the current density of each arc column, improves the contact space utilization rate, reduces the arc ablation intensity, and finally improves the breaking capacity.

[0006] The purpose of the present invention is achieved through the following technical solutions.

[0007] A large-capacity circuit breaker vacuum interrupter contact structure comprises:

[0008] Contact body,

[0009] Multiple slots extending from the edge of the contact body toward the center to increase the magnetic field and reduce eddy currents.

[0010] A plurality of blocking grooves are provided between two adjacent slots to block the movement of the contact arc.

[0011] The slot projection is a vertical projection of the slot on another contact sheet body relative to the contact sheet body onto the contact sheet body, and the slot projection at least partially overlaps the slot and at least partially overlaps the blocking slot.

[0012] In the large-capacity circuit breaker vacuum interrupter contact structure, the contact piece body is provided with an extended contact cup.

[0013] In the large-capacity circuit breaker vacuum interrupter contact structure, the blocking groove is a through groove or a groove.

[0014] In the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the contact piece body is arranged on the static contact, and the other contact piece body is arranged on the moving contact; or the contact piece body is arranged on the moving contact, and the other contact piece body is arranged on the static contact.

[0015] In the large-capacity circuit breaker vacuum interrupter contact structure, the extending direction of the blocking groove is perpendicular to the radial direction to form a tangential blocking groove that blocks the arc at the edge of the contact body from moving toward the center.

[0016] In the large-capacity circuit breaker vacuum interrupter contact structure, the blocking groove is arc-shaped.

[0017] In the contact structure of the vacuum interrupter chamber of the large-capacity circuit breaker, the contact body is provided with a contact center groove at the center, the blocking groove extends radially and the distance between the blocking groove and the slot gradually increases in the direction from the center to the edge, so as to block the tangential movement of the arc and block the arc from moving to the center.

[0018] The contact structure of the vacuum arc chamber of the large-capacity circuit breaker also includes a blocking groove projection, which is a blocking groove on another contact piece body relative to the contact piece body, projected vertically onto the contact piece body, and the blocking groove projection at least partially overlaps the slot and at least partially overlaps the blocking groove, and the slot, blocking groove, slot projection and blocking groove projection form a W shape.

[0019] In the large-capacity circuit breaker vacuum interrupter contact structure, the blocking groove is a straight groove.

[0020] In the large-capacity circuit breaker vacuum interrupter contact structure, the blocking groove is L-shaped or T-shaped.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention significantly blocks arcs in multiple areas from moving radially to the center of the contact or moving tangentially to gather, so that multiple arc columns exist in the contact gap for a long time, reducing the current density of the arc column, improving the contact space utilization rate, reducing the arc ablation intensity, and greatly improving the breaking capacity of the vacuum interrupter. Specifically,

[0023] The present invention actually discloses an improved contact structure of a vacuum interrupter for a large-capacity circuit breaker, which is intended to improve arc control and reduce arc damage to the contact through innovatively designed slots and blocking slots. Regarding its various components and how they work together to achieve the technical effect, it is:

[0024] Contact body: As the basic part of the contact, it carries all other structural features. The contact body forms the contact point between the stationary contact and the moving contact, and when the circuit breaker is operated, the two contacts will separate to cut off the current.

[0025] Multiple slots: These slots extend from the edge of the contact piece to the center, and their main purpose is to increase the magnetic field effect and reduce eddy currents. The slots can change the magnetic field distribution, so that a radial component of the magnetic field (i.e., transverse magnetic field) is generated near the root of the arc. It can also be used as an extension of the contact cup slot to enhance the magnetic field, which helps stabilize the arc and reduce concentration or make the arc move in a circular motion to reduce local ablation. At the same time, the slots can also divide the conductive path on the contact surface, reducing the intensity of eddy currents, which will cause heat concentration and weaken the magnetic field.

[0026] Multiple blocking grooves: set between two adjacent slots to prevent the arc from moving from the edge of the contact to the center. The blocking groove can be a through groove or a groove, and its shape can be a straight groove, L-shaped, T-shaped or arc-shaped, depending on the specific design requirements. The existence of the blocking groove increases the resistance to the movement of the arc, making it difficult for multiple arcs to converge together. The arc convergence often leads to an increase in current density and temperature, affecting the breaking capacity.

[0027] Slot projection and blocking groove projection: This refers to the overlap of the corresponding structure on the other contact piece vertically projected onto the current contact piece. This design ensures that even in the case of relative movement of the contacts (such as the opening and closing action between the moving and static contacts), the slots and blocking grooves on the two contacts can effectively cooperate to maintain arc confinement and control. In particular, the W-shaped structure mentioned means that the arrangement of the slots and blocking grooves can complement each other and further enhance the control of the arc path.

[0028] Contact center groove: Located in the center of the contact, it can limit the movement of the arc and prevent it from gathering in the center of the contact. The arc usually tends to gather in the center of the contact, and the center of the contact is usually where the arc is most likely to cause serious damage. The contact center groove provides a lot of resistance to the movement of the arc toward the center, which can effectively prevent the arc from gathering in the center.

[0029] Thus, the various structural features described in the invention work together to optimize arc behavior, disperse arc energy, reduce arc damage to contacts, and improve the breaking capacity and service life of the circuit breaker. By rationally arranging the slots and blocking slots and considering the projection relationship between them, good arc control can be continuously provided in different states, thereby ensuring safe and reliable operation of the circuit breaker.

[0030] The above description is only an overview of the technical solution of the present invention. In order to make the technical means of the present invention clearer and to achieve the extent that those skilled in the art can implement it according to the contents of the specification, and in order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are exemplified below. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0032] In the attached picture:

[0033] Figure 1 A top view of an embodiment of a contact sheet of the present invention;

[0034] Figure 2 A top view of another embodiment of a contact sheet of the present invention;

[0035] Figure 3 Another embodiment of the contact sheet of the present invention is a top view of the projection of the slots of the moving and static contacts;

[0036] Figure 4 A top view of another embodiment of a contact sheet of the present invention;

[0037] Figure 5 The figure is a top view of another contact sheet implementation example of the present invention.

[0038] The present invention is further explained below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0039] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0040] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0041] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0042] For a better understanding, Figures 1 to 5 As shown, a large-capacity circuit breaker vacuum interrupter contact structure includes:

[0043] Contact piece body 1,

[0044] A plurality of slots 2 extend from the edge of the contact body 1 toward the center thereof to increase the magnetic field and reduce eddy currents.

[0045] A plurality of blocking grooves 4 are provided between two adjacent slots 2 to block the movement of the contact arc.

[0046] The slot projection 3 is a vertical projection of a slot on another contact sheet body 1 relative to the contact sheet body 1 onto the contact sheet body 1 , and the slot projection 3 at least partially overlaps the slot 2 and at least partially overlaps the blocking slot 4 .

[0047] In a preferred embodiment of the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the contact piece body 1 is provided with an extended contact cup.

[0048] In a preferred embodiment of the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the blocking groove 4 is a through groove or a groove.

[0049] In a preferred embodiment of the contact structure of the vacuum interrupter of a large-capacity circuit breaker, the contact piece body 1 is arranged on the static contact, and another contact piece body is arranged on the moving contact; or the contact piece body 1 is arranged on the moving contact, and another contact piece body is arranged on the static contact.

[0050] In a preferred embodiment of the large-capacity circuit breaker vacuum interrupter contact structure, the blocking groove 4 extends in a direction perpendicular to the radial direction to form a tangential blocking groove 4 that blocks the arc at the edge of the contact body from moving toward the center.

[0051] In the preferred embodiment of the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the blocking groove 4 is arc-shaped.

[0052] In a preferred embodiment of the contact structure of the vacuum interrupter chamber of the large-capacity circuit breaker, the contact body is provided with a contact center groove 6 at the center, the blocking groove 4 extends radially and the distance between the blocking groove 4 and the slot 2 gradually increases in the direction from the center to the edge, so as to block the tangential movement of the arc and block the arc from moving to the center.

[0053] In a preferred embodiment of the contact structure of the vacuum interrupter of a large-capacity circuit breaker, it also includes a blocking groove projection 5, which is a vertical projection of a blocking groove 4 on another contact piece body 1 relative to the contact piece body 1 onto the contact piece body 1, and the blocking groove projection 5 at least partially overlaps the slot 2 and at least partially overlaps the blocking groove 4, and the slot 2, the blocking groove 4, the slot projection 3 and the blocking groove projection 5 form a W shape.

[0054] In the preferred embodiment of the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the blocking groove 4 is a straight groove.

[0055] In the preferred embodiment of the contact structure of the vacuum interrupter of the large-capacity circuit breaker, the blocking groove 4 is L-shaped or T-shaped.

[0056] In one embodiment, one or more blocking grooves 4 are arranged between two slots 2 or at a position where there is no slot 2 in the center of the contact. The blocking grooves 4 block the movement of the arc and delay the arc convergence in multiple areas, making the contact piece more suitable for large current breaking conditions. The blocking grooves 4 are opened in a symmetrical manner along the center of the contact. The blocking grooves 4 of the moving contact piece and the static contact piece are opened in exactly the same manner.

[0057] In one embodiment, the shape of the blocking groove 4 has a radial component or a tangential component. The radial component of the blocking groove 4 is used to block the tangential movement of the arc, and the tangential component is used to block the radial movement of the arc.

[0058] In one embodiment, the blocking groove 4 is a tangential through groove, which is perpendicular to the radial direction and blocks the arc outside the tangential through groove from moving inside, so that arcs in multiple regions are not easily gathered to the center of the contact to achieve aggregation, which can effectively reduce the current density and arc ablation intensity, and improve the breaking capacity. The direction of the slot 2 is radial along the radial direction of the contact radius. The arcs in multiple regions are blocked from moving tangentially along the contact to avoid arc aggregation. The slot 2 method has both radial and lateral components. The shape of the slot 2 can be V-shaped, L-shaped, I-shaped, etc. The arcs in multiple regions are blocked from moving radially along the contact to the center of the contact or moving tangentially to gather.

[0059] In one embodiment, Figure 1 As shown, the vacuum interrupter contact piece of this embodiment includes a contact piece body 1, a contact cup is extended on the contact, a slot 2 for increasing the magnetic field and reducing the eddy current, and a slot projection 3 of the slot of the contact piece body on the other contact on the contact piece body 1 when the switch is closed, and a tangential blocking groove 4 is added on the contact piece, the blocking groove 4 can be a through groove or a groove, and the extension direction of the tangential blocking groove is perpendicular to the radial direction. It is arranged between the two slots 2 of the contact piece body 1. The purpose is to prevent the arc at the edge of the contact from moving toward the center, thereby preventing the arc from converging at the center of the contact.

[0060] The specific embodiment 2 provided by the present invention is as follows Figure 2 As shown, this embodiment includes a contact piece body 1, a slot 2, a radial blocking slot 4 and a contact center slot 6 are added to the contact piece body 1, and the radial blocking slot 4 extends in the radial direction to block the tangential movement of the arc and prevent the arc from merging. At the same time, the blocking slot 4 cooperates with the slot 2, and the slot spacing away from the center of the contact piece body 1 is large, and the slot spacing close to the center of the contact piece body 1 is small, which can block the arc from moving to the contact center to a certain extent. At the same time, the contact center slot 6 of the contact piece body 1 can block the arc from completely moving to the contact center, preventing the arc from gathering in the weak longitudinal magnetic field area and being difficult to spread.

[0061] Consider that the contact pieces of both the moving and static contacts have the same slotting method, such as Figure 3 As shown, in addition to the contact piece body 1, slot 2, blocking slot 4, and contact center groove 6 of the present contact, it also includes a slot projection 3 and a blocking slot projection 5 that are vertically projected from the contact piece slot of another contact onto the contact piece body 1 of the present contact. The vacuum arc is generated by the metal vapor of the two contact pieces. The essence of blocking the movement of the arc is to block the movement of the arc burning zone of the contact piece. The slot on the present contact piece body 1 has a stronger blocking effect on the movement of the arc burning zone of the contact piece, while the slot of the other contact piece has a weaker blocking effect on its movement. Figure 3In the embodiment, the projection of the slot of the contact piece body and the slot of another contact piece are combined into a "W" shape, which blocks the arc outside the contact piece from moving toward the center. At the same time, the blocking strength on the contact piece body is distributed in a "strong, weak, strong, weak" manner, while the blocking strength on the other contact piece is opposite to the contact piece body and is distributed in a "weak, strong, weak, strong" manner. The two contact pieces work together to completely isolate the connection between the outside and inside of the contact, evenly block the arc movement, and also block the tangential movement of the arc, so that the arc will not gather in one place.

[0062] The specific embodiment 3 of the contact sheet provided by the present invention is as follows Figure 3 to Figure 4 As shown, this embodiment combines the two features of radial blocking groove and tangential blocking groove. The contact piece presents blocking grooves in the shape of "L-shaped" and "T-shaped". It can block the radial movement and tangential movement of the arc at the same time.

[0063] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0064] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A large-capacity circuit breaker vacuum interrupter contact structure, characterized in that: These include, Contact piece body, Multiple slots extending from the edge of the contact body toward the center to increase the magnetic field and reduce eddy currents. A plurality of blocking grooves are provided between two adjacent slots to block the movement of the contact arc. The slot projection is a vertical projection of the slot on another contact sheet body relative to the contact sheet body onto the contact sheet body, and the slot projection at least partially overlaps the slot and at least partially overlaps the blocking slot.

2. The large-capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: Preferably, the contact piece body is provided with an extended contact cup.

3. The large-capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: The blocking groove is a through groove or a groove.

4. The large-capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: The contact piece body is arranged on the stationary contact, and the other contact piece body is arranged on the moving contact; or the contact piece body is arranged on the moving contact, and the other contact piece body is arranged on the stationary contact.

5. The large capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: The extending direction of the blocking groove is perpendicular to the radial direction to form a tangential blocking groove that blocks the arc at the edge of the contact body from moving toward the center.

6. The large capacity circuit breaker vacuum interrupter contact structure as claimed in claim 5, characterized in that: The blocking groove is arc-shaped.

7. The large capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: The contact body is provided with a contact center groove at the center, the blocking groove extends radially, and the distance between the blocking groove and the slot gradually increases in the direction from the center to the edge, so as to block the tangential movement of the arc and block the arc from moving to the center.

8. The large capacity circuit breaker vacuum interrupter contact structure as claimed in claim 7, characterized in that: It also includes a blocking groove projection, which is a blocking groove on another contact piece body relative to the contact piece body and is vertically projected onto the contact piece body, the blocking groove projection at least partially overlaps the slot and at least partially overlaps the blocking groove, and the slot, blocking groove, slot projection and blocking groove projection form a W shape.

9. The large capacity circuit breaker vacuum interrupter contact structure according to claim 7, characterized in that: The blocking groove is a straight groove.

10. The large capacity circuit breaker vacuum interrupter contact structure according to claim 1, characterized in that: The blocking groove is L-shaped or T-shaped.

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