Contact system for direct current circuit breaker
By installing arc-initiating plates on the stationary and moving contacts of the DC circuit breaker, combined with the arc-extinguishing chamber, dual-path arc initiation is achieved, solving the problem of poor arc-extinguishing effect in the existing technology and improving the arc-extinguishing effect and the durability of the contact system.
Patent Information
- Application Number
- CN202423285946.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2034-12-30
AI Technical Summary
The existing contact system of DC circuit breakers is inadequate in terms of arc extinguishing effect, especially the moving contact may retain an arc after the circuit is opened, which may lead to damage to the contact system.
By setting arc-inducing plates on both the stationary and moving contacts, and combining them with the arc-extinguishing chamber, the arc is induced through the stationary contact arc-inducing plate when the stationary contact is closed, and through the moving contact arc-inducing plate when the moving contact is opened, forming a dual-path arc induction and enhancing the arc-extinguishing effect.
By employing a dual-path arc ignition method, the arc extinguishing performance of the contact system is significantly improved, arc leakage is reduced, and the service life of the contact system is extended.
Smart Images
Figure CN223665397U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a circuit breaker more specifically relates to a contact system for direct current circuit breaker. BACKGROUND
[0002] The breaking performance of the circuit breaker mainly depends on its arc extinguishing performance, that is, whether the circuit breaker can successfully break and whether the arc can be quickly extinguished. The direct current arc is different from the alternating current arc, and the direct current arc has no natural zero point, so it is more difficult to extinguish the arc. For the traditional mechanical circuit breaker, to break the high-voltage arc, a plurality of poles are usually connected in series to increase the arc voltage and force the arc current to zero, thereby extinguishing the direct current arc.
[0003] At present, in the prior art, in order to avoid the influence of the arc on the contact system, most of the high-voltage direct current circuit breakers adopt the mode of moving the arc extinguishing chamber away from the contact system, and then achieving the effect of arc drawing by setting an arc drawing plate at the static contact. However, the above-mentioned single-sided arc drawing mode may cause a part of the arc to remain on the moving contact after the moving contact is opened, and if the part of the arc is not processed in time, it is easy to flow back to the moving contact, thereby causing damage to the entire contact system. Therefore, the arc extinguishing effect of the contact system in the prior art still has certain deficiencies. SUMMARY
[0004] In view of the deficiencies in the prior art, the purpose of the utility model is to provide a contact system for a direct current circuit breaker with sufficient arc extinguishing effect.
[0005] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a contact system for a direct current circuit breaker, comprising a static contact, a moving contact and an arc extinguishing chamber, the arc extinguishing chamber is arranged between the static contact and the moving contact, characterized in that: a static contact arc drawing plate is arranged between the static contact and the arc extinguishing chamber, and a moving contact arc drawing plate is arranged between the moving contact and the arc extinguishing chamber, so that when the static contact and the moving contact are closed or just opened, the static contact arc drawing plate draws the arc, and when the static contact and the moving contact are opened, the moving contact arc drawing plate draws the arc.
[0006] As a further improvement of the utility model, the static contact arc drawing plate comprises an arc drawing piece and an insulating plate, the insulating plate is installed on one side of the arc drawing piece and is bent along with the bending of the arc drawing piece, and extends along the length of the arc drawing piece, one end of the insulating plate extending towards the static contact extends to the static contact and covers the static contact, so that only the contact point on the side of the static contact facing the moving contact is exposed.
[0007] As a further improvement of the utility model, one side of the insulating plate is fixed with two convex ribs side by side, and the arc drawing piece is embedded between the two convex ribs.
[0008] As a further improvement of the utility model, the moving contact head includes a contact head row and an arc leading rod, the contact of the static contact head is a long strip structure, the arc leading rod is located at the middle position of the contact head row, and one end of the arc leading rod away from the contact head row is an arc leading end.
[0009] As a further improvement of the utility model, the moving contact head arc leading plate includes a mounting sheet and a connecting sheet, the mounting sheet is a square sheet structure, is fixed to the external shell through the bolt passing through the mounting sheet, one end of the connecting sheet is fixed with the mounting sheet, and the other end is bent towards the inner wall of the external shell to form an arc leading end.
[0010] As a further improvement of the utility model, the moving contact head and the static contact head are provided with an insulating cover, the insulating cover includes a fixed plate and a separation plate, one side of the separation plate is fixed with the side of the fixed plate, so that the insulating cover forms an L-shaped plate structure, two extension plates are fixed on the side of the separation plate towards the contact of the static contact head, the two extension plates and the separation plate form a cavity towards the opening of the arc extinguishing chamber, and the cavity contains the contact of the static contact head and the contact head row.
[0011] The utility model discloses the beneficial effects, through the setting of static contact head, moving contact head and arc extinguishing chamber, can effectively realize the structure of a contact head system, and through the setting of static contact head arc leading plate and moving contact head arc leading plate, can effectively realize when static contact head and moving contact head close or just open, utilize static contact head arc leading plate to realize arc leading, and the arc remaining after moving contact head opens is led by moving contact head arc leading plate, so compared with the mode in the prior art, realize the effect of double -way arc leading, greatly increase the arc extinguishing effect of contact head system. BRIEF DESCRIPTION OF DRAWINGS
[0012] Figure 1 It is the structure schematic diagram of the DC circuit breaker of the contact head system of the utility model,
[0013] Figure 2 It is the structure schematic diagram of the contact head system for DC circuit breaker of the utility model,
[0014] Figure 3 It is Figure 2 The structure schematic diagram of moving contact head in, DETAILED DESCRIPTION
[0015] The utility model will be further described in the embodiment given below in conjunction with the drawings.
[0016] Refer to Figures 1 to 3As shown, the contact system for a direct current circuit breaker of the embodiment comprises a static contact 2, a moving contact 3 and an arc extinguishing chamber 4, which is arranged in a spaced manner between the static contact 2 and the moving contact 3, characterized in that: a static contact arc guiding plate 51 is arranged between the static contact 2 and the arc extinguishing chamber 4, and a moving contact arc guiding plate 52 is arranged between the moving contact 3 and the arc extinguishing chamber 4, so that when the static contact 2 and the moving contact 3 are closed or just opened, the arc is guided by the static contact arc guiding plate 51, and after the static contact 2 and the moving contact 3 are opened, the arc is guided by the moving contact arc guiding plate 52. In the process of using the contact system of the embodiment, the bottom plate and the base internal space constituting the external shell are divided into a contact area and an arc extinguishing area, the moving contact 3 and the static contact 2 are installed in the contact area, and the arc extinguishing chamber 4 is installed in the arc extinguishing area. Then, through the arrangement of the static contact arc guiding plate 51 and the moving contact arc guiding plate 52, the arc in the contact area can be effectively guided to the arc extinguishing chamber 4 in the arc extinguishing area in a double path. Compared with the structure of the direct current circuit breaker in the prior art, on the one hand, the isolation between the arc extinguishing chamber 4 and the static contact 2 and the moving contact 4 is realized, and on the other hand, the arc guiding is ensured, and the arc extinguishing effect is ensured.
[0017] In order to further increase the arc extinguishing effect, the static contact arc guiding plate 51 in the embodiment is composed of an arc guiding sheet 511 and an insulating plate 512. In this way, the material of the insulating plate 512 can release gas under the action of high temperature of the arc to accelerate the cooling of the arc. The arc guiding sheet 511 and the insulating plate 512 are arranged in a close manner, which can ensure the effect of gas production during the arc guiding process, thereby increasing the arc extinguishing effect. Further, two parallel protrusions 513 are arranged on the insulating plate 512, and the protrusions 513 are higher than the surface of the arc guiding sheet 511, which can reduce the arc leakage during the arc guiding process, thereby further increasing the arc extinguishing performance of the circuit breaker structure.
[0018] In order to better guide the arc on the moving contact 3 out, the moving contact 3 in the embodiment adopts the following structure, the moving contact 3 includes a contact row 31 and an arc leading rod 32, the contact of the static contact 2 is a long strip structure, the arc leading rod 32 is located at the middle position of the contact row 31, and one end of the arc leading rod 32 away from the contact row 31 is an arc leading end. When the moving contact 3 is closed, the arc leading end is close to the end of the arc leading piece 511. When the moving contact 3 is opened, the arc leading end is close to the end of the moving contact arc leading plate 52. Thus, the arc leading effect of the arc leading rod 32 can be used to guide the arc on the moving contact 3 out, so that the arc can be better guided to the moving contact arc leading plate 52, thereby enhancing the arc extinguishing performance. In practice, the number of the arc leading rod 32 can be 2-3, and arc contacts made of arc-resistant conductive materials are welded at the ends of the arc leading rod 32 or arc contacts made of red copper materials are integrally cut with the moving contact 3. In this way, when the switch is closed, the arc contacts at the upper end of the arc leading rod 32 first contact the arc leading piece 511 on the static contact 2, and when the switch is opened, the arc contacts are finally separated from the arc leading piece 511, thereby playing an arc leading role and protecting the main contact from being ablated. In the embodiment, the arc leading rod 32 is staggered by 1-2°, and the switch has a longer electrical life than the synchronous closing and opening structure of the moving contact 3. At the same time, the following structure of the moving contact arc leading plate 52 is also adopted to facilitate the installation of the moving contact arc leading plate 52 and the accommodation of the arc at the end of the arc leading rod 32. Specifically, the moving contact arc leading plate 52 includes a mounting piece 521 and a connecting piece 522. The mounting piece 521 is a square piece structure, which is fixed to the external base through a bolt passing through the mounting piece 521. One end of the connecting piece 522 is fixed to the mounting piece 521, and the other end is bent towards the inner wall of the base 1 to form an arc receiving end.
[0019] In the embodiment, the insulating cover 7 is installed between the moving contact 3 and the static contact 2 to separate the contact area and the arc extinguishing area between the external bottom plate and the base, thereby facilitating the mold opening production of the circuit breaker. Further, the insulating cover 7 is combined with the fixing plate 71 and the isolation plate 72, which can facilitate the installation of the insulating cover 7. At the same time, two extension plates are fixed to the side of the isolation plate 72 facing the contact of the static contact 2. The two extension plates and the isolation plate 72 form a cavity opening towards the arc extinguishing area, and the cavity accommodates the contact of the static contact 2 and the contact row 31. This can effectively avoid the arc missing when the contact of the static contact 2 and the contact row 31 are closed and opened, effectively enhance the insulation effect, and the insulating cover 7 can always isolate the contact of the static contact 2 from the space below in the base 1, so as to make the arc move towards the arc extinguishing chamber 4 and improve the arc extinguishing reliability. Figure 1
[0020] In summary, the contact system for the DC circuit breaker in the embodiment can realize double-way arc leading after closing and opening through the static contact arc leading plate 51 and the moving contact arc leading plate 52, thereby effectively enhancing the arc extinguishing performance of the contact system.
[0021] The above merely describes preferred embodiments of the present application, and the protection scope of the present application is not limited to the above-mentioned embodiments. Any technical solution falling within the concept of the present application shall fall within the protection scope of the present application. It should be noted that, for ordinary skilled persons in the art, some improvements and refinements without departing from the principles of the present application shall also be considered as falling within the protection scope of the present application.
Claims
1. A contact system for a DC circuit breaker, comprising a stationary contact (2), a moving contact (3), and an arc-extinguishing chamber (4), wherein the arc-extinguishing chamber (4) is spaced apart from the stationary contact (2) and the moving contact (3), characterized in that: A stationary contact arc-inducing plate (51) is provided between the stationary contact (2) and the arc-extinguishing chamber (4), and a moving contact arc-inducing plate (52) is provided between the moving contact (3) and the arc-extinguishing chamber (4) so that when the stationary contact (2) and the moving contact (3) are closed or just opened, an arc is induced through the stationary contact arc-inducing plate (51), and after the stationary contact (2) and the moving contact (3) are opened, an arc is induced through the moving contact arc-inducing plate (52).
2. The contact system for a DC circuit breaker according to claim 1, characterized in that: The stationary contact arc-starting plate (51) includes an arc-starting piece (511) and an insulating plate (512). The insulating plate (512) is mounted on one side of the arc-starting piece (511) and bends as the arc-starting piece (511) bends. It extends along the length of the arc-starting piece (511). The insulating plate (512) extends to the stationary contact (2) at one end and covers the stationary contact (2), so that only the contact point is exposed on the side of the stationary contact (2) facing the moving contact (3).
3. The contact system for a DC circuit breaker according to claim 2, characterized in that: Two parallel ribs (513) are fixed on one side of the insulating plate (512), and the arc-guiding piece (511) is embedded between the two ribs (513).
4. The contact system for a DC circuit breaker according to claim 3, characterized in that: The moving contact (3) includes a contact row (31) and an arc-inducing rod (32). The contact point of the stationary contact (2) is a long strip structure. The arc-inducing rod (32) is located in the middle of the contact row (31). The end of the arc-inducing rod (32) facing away from the contact row (31) is the arc-inducing end. When the moving contact (3) is closed, the arc-inducing end is close to the end of the arc-inducing plate (511). When the moving contact (3) is open, the arc-inducing end is close to the end of the moving contact arc-inducing plate (52).
5. The contact system for a DC circuit breaker according to claim 4, characterized in that: The moving contact arc-inducing plate (52) includes a mounting plate (521) and a connecting plate (522). The mounting plate (521) is a square plate structure. It is fixed to the outer housing by bolts passing through the mounting plate (521). One end of the connecting plate (522) is fixed to the mounting plate (521), and the other end is bent toward the inner wall of the outer housing to form an arc-connecting end.
6. The contact system for a DC circuit breaker according to claim 5, characterized in that: An insulating cover (7) is installed between the moving contact (3) and the stationary contact (2). The insulating cover (7) includes a fixed plate (71) and an isolation plate (72). One side of the isolation plate (72) is fixed to the side of the fixed plate (71) so that the insulating cover (7) forms an L-shaped plate structure. Two extension plates are fixed on the side of the isolation plate (72) facing the contact point of the stationary contact (2). The two extension plates and the isolation plate (72) form a cavity that opens towards the arc-extinguishing chamber (4) and the cavity accommodates the contact point and contact row (31) of the stationary contact (2).