DC circuit breaker structure

Abstract

The present invention discloses a DC circuit breaker structure, including a bottom plate, a base, a static contact, a moving contact and an arc extinguishing chamber, wherein the base and the bottom plate are spliced ​​to each other on the left and right to form a contact area and an arc extinguishing area, wherein the static contact and the moving contact are arranged in the contact area, wherein the arc extinguishing chamber is arranged in the arc extinguishing area, wherein the static contact is mounted on the bottom plate, and the moving contact is mounted on the base, wherein an arc striking plate is arranged between the contact area and the arc extinguishing area, wherein the arc striking plate is arranged on the inner side wall of the base, wherein one end extends to the contact area, and the other end extends to the arc extinguishing area. The DC circuit breaker structure of the present invention can effectively constitute a DC circuit breaker structure through the arrangement of the bottom plate, the base, the static contact, the moving contact and the arc extinguishing chamber, and by partitioning the space in the base and the bottom plate and connecting them through the arc striking plate, the effect of having a larger arc extinguishing space can be achieved, thereby achieving a better arc extinguishing effect.

Description

Technical Field

[0001] The present invention relates to a DC circuit breaker, and more particularly to a DC circuit breaker structure. Background Art

[0002] The breaking performance of a circuit breaker mainly depends on its arc extinguishing performance, that is, whether the circuit breaker can successfully break and whether the arc can be extinguished quickly. DC arcs are different from AC arcs. DC arcs do not have a natural zero crossing point, so arc extinguishing is more difficult. For traditional mechanical circuit breakers, to break high-voltage arcs, multiple poles are usually connected in series to increase the arc voltage and force the arc current to cross zero, thereby extinguishing the DC arc.

[0003] Therefore, in the prior art, there is an invention patent with publication number CN112490094B, entitled A current-limiting air DC circuit breaker arc extinguishing device and arc extinguishing method thereof, which discloses a method of enhancing the arc extinguishing effect of the circuit breaker by setting two parallel arc extinguishing chambers. However, due to the trend of miniaturization, the distance between the arc extinguishing chamber of the circuit breaker and the moving contact and the static contact is relatively close. Therefore, during use, the arc that has not been extinguished in time is easy to run into the static contact and the moving contact, and then burn the static contact and the moving contact. Therefore, the arc extinguishing effect of the existing circuit breaker structure still has certain shortcomings. Summary of the invention

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide a DC circuit breaker structure with better arc extinguishing effect.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a DC circuit breaker structure, comprising a bottom plate, a base, a static contact, a moving contact and an arc extinguishing chamber, characterized in that: the base and the bottom plate are spliced ​​to each other on the left and right to form a contact area and an arc extinguishing area, the static contact and the moving contact are arranged in the contact area, the arc extinguishing chamber is arranged in the arc extinguishing area, the static contact is installed on the bottom plate, and the moving contact is installed on the base, an arc-starting plate is provided between the contact area and the arc extinguishing area, the arc-starting plate is fitted on the inner side wall of the base, one end of the arc-starting plate extends to the contact area, and the other end extends into the arc extinguishing area, so as to guide the arc generated by the static contact and the moving contact into the arc extinguishing chamber in the arc extinguishing area for arc extinguishing.

[0006] As a further improvement of the present invention, the width of the arc extinguishing zone is greater than the width of the contact zone, the base has an inclined transition relative to the side wall between the arc extinguishing zone and the contact zone, the arc striking plate includes a static contact arc striking plate attached to the inner wall of the bottom plate and a moving contact arc striking plate attached to the inner wall of the base, one end of the static contact arc striking plate extends into the contact zone and is arranged close to the static contact, the other end extends to the arc extinguishing zone and is located in the arc extinguishing chamber, one end of the moving contact arc striking plate extends into the contact zone, and when the moving contact is in the open state, the end is close to the moving contact, the other end extends to the arc extinguishing zone and is located in the arc extinguishing chamber.

[0007] As a further improvement of the present invention, the static contact arc-starting plate includes an arc-starting plate and an insulating plate. The insulating plate is installed on the side of the arc-starting plate facing the base plate, and bends as the arc-starting plate bends, and extends along the length of the arc-starting plate. The insulating plate extends to the static contact from one end toward the static contact, and covers the static contact, so that only the contact point is exposed on the side of the static contact facing the moving contact.

[0008] As a further improvement of the present invention, two convex ribs arranged side by side with each other are fixed on the side of the insulating plate facing away from the bottom plate, and the arc-starting sheet is embedded between the two convex ribs.

[0009] As a further improvement of the present invention, the moving contact includes a contact row and an arc-striking rod, the contact point of the static contact is a long strip structure, the arc-striking rod is located in the middle position of the contact row, and the end of the arc-striking rod facing away from the contact row is the arc-striking end. When the moving contact is closed, the arc-striking end and the end of the arc-striking plate are close to each other, and when the moving contact is opened, the arc-striking end and the end of the arc-striking plate of the moving contact are close to each other.

[0010] As a further improvement of the present invention, the moving contact arc-starting plate includes a mounting plate and a connecting plate. The mounting plate is a square plate structure and is fixed to the base by bolts passing through the mounting plate. One end of the connecting plate is fixed to the mounting plate, and the other end is bent toward the inner wall of the base to form an arc-connecting end.

[0011] As a further improvement of the present invention, an insulating cover is installed between the moving contact and the stationary contact, and the insulating cover is located between the contact area and the arc extinguishing area to divide the internal space after the base and the bottom plate are assembled into the contact area and the arc extinguishing area.

[0012] As a further improvement of the present invention, the insulating cover includes a fixed plate and an isolation plate, one side of the isolation plate is fixed to the side of the fixed plate so that the insulating cover forms an L-shaped plate structure, and two extension plates are fixed to the side of the isolation plate facing the static contact point, the two extension plates and the isolation plate form a cavity opening toward the arc extinguishing zone, and the cavity accommodates the static contact point and contact row.

[0013] The beneficial effect of the present invention is that a DC circuit breaker structure can be formed by arranging a bottom plate, a base, a static contact, a moving contact and an arc extinguishing chamber, and by forming a contact area and an arc extinguishing area in the internal space of the base and the bottom plate, the two can be isolated from each other, reducing the influence of the arc on the operation of the moving contact and the static contact, and by arranging an arc-starting plate, the arc can be effectively guided into the arc extinguishing chamber for arc extinguishing, thereby better enhancing the arc extinguishing effect of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1is a schematic diagram of the internal structure of a DC circuit breaker;

[0015] Figure 2 for Figure 1 Structural diagram of the moving contact and the stationary contact;

[0016] Figure 3 for Figure 2 Schematic diagram of the structure of the moving contact part. DETAILED DESCRIPTION

[0017] The present invention will be further described below in detail with reference to the embodiments shown in the accompanying drawings.

[0018] Reference Figures 1 to 3 As shown, a DC circuit breaker structure of this embodiment includes a bottom plate 6, a base 1, a static contact 2 and a moving contact 3, and an arc extinguishing chamber 4. The base 1 and the bottom plate 6 are spliced ​​to each other on the left and right to form a contact area 11 and an arc extinguishing area 12. The static contact 2 and the moving contact 3 are arranged in the contact area 11, and the arc extinguishing chamber 4 is arranged in the arc extinguishing area 12. The static contact 2 is installed on the bottom plate 6, and the moving contact 3 is installed on the base 1. An arc-starting plate 5 is provided between the contact area 11 and the arc extinguishing area 12. The arc-starting plate 5 is fitted on the inner side wall of the base 1, and one end extends to the contact area 11, and the other end extends to the arc extinguishing area 12. , so as to guide the arc generated by the static contact 2 and the moving contact 3 into the arc extinguishing chamber 4 in the arc extinguishing zone 12 for arc extinguishing. In the process of using the DC circuit breaker structure of this embodiment, it is only necessary to connect the static contact 2 and the moving contact 3 to the external circuit. Since the space inside the bottom plate 6 and the base 1 is divided into the contact zone 11 and the arc extinguishing zone 12, the influence of the arc on some electronic circuits of the moving contact 3 can be avoided. Then, the arc striking effect can be effectively achieved by means of the arc striking plate 5. Compared with the method in the prior art, the setting freedom of the arc extinguishing zone 12 is higher, and therefore it also has a better arc extinguishing effect.

[0019] Furthermore, in order to better utilize the structural arrangement of the contact area 11 and the arc extinguishing area 12 in this embodiment, the width of the arc extinguishing area 12 is made greater than the width of the contact area 11, such as Figure 1As shown, the upper ends of the bottom plate 6 and the base 1 present a wider structure, forming an outwardly expanded structure, so that it can accommodate more arc-extinguishing plates and have a better arc-extinguishing effect. The side wall of the base 1 relative to the arc-extinguishing zone 12 and the contact zone 11 is an inclined transition. The arc-starting plate 5 includes a static contact arc-starting plate 51 attached to the inner wall of the bottom plate 6 and a dynamic contact arc-starting plate 52 attached to the inner wall of the base 1. One end of the static contact arc-starting plate 51 extends into the contact zone 11 and is arranged close to the static contact 2, and the other end extends to the arc-extinguishing zone 12 and is in the arc-extinguishing chamber 4. One end of the moving contact arc-starting plate 52 extends into the contact area 11, and when the moving contact 3 is in the open state, the end is close to the moving contact 3, and the other end extends to the arc extinguishing area 12 and is in the arc extinguishing chamber 4. The further use of the static contact arc-starting plate 51 and the moving contact arc-starting plate 52 can form an arc track at the bottom plate 6 for arc drainage when closing or just opening the switch, and at the same time, an arc track is formed at the base 1 for arc drainage of the moving contact 3 after opening, thereby achieving a dual-path arc-starting effect, which has a better arc extinguishing effect than the single-path arc-starting method.

[0020] In order to further enhance the arc extinguishing effect, the present embodiment adopts a combined structure of an arc-striking plate 511 and an insulating plate 512 to form the static contact arc-striking plate 51. In this way, the material of the insulating plate 512 can be used to produce gas at high temperature, release gas under the action of the high temperature of the arc, and accelerate the cooling of the arc. The arc-striking plate 511 and the insulating plate 512 are always attached to each other, which can ensure the effect of producing gas during the arc guiding process, thereby enhancing the arc extinguishing effect. Furthermore, in the present embodiment, two side-by-side ribs 513 are arranged on the insulating plate 512, and the ribs 513 are raised above the surface of the arc-striking plate 511, so as to reduce arc leakage during the arc striking process, thereby further enhancing the arc extinguishing performance of the present circuit breaker structure.

[0021] In order to better lead out the arc on the moving contact 3 in this embodiment, this embodiment adopts the following structure of the moving contact 3, the moving contact 3 includes a contact row 31 and an arc-striking rod 32, the contact point of the static contact 2 is a long strip structure, the arc-striking rod 32 is located in the middle position of the contact row 31, and the end of the arc-striking rod 32 facing away from the contact row 31 is the arc-striking end. When the moving contact 3 is closed, the arc-striking end is close to the end of the arc-striking plate 511, and when the moving contact 3 is opened, the arc-striking end is close to the end of the moving contact arc-striking plate 52, thereby arc-striking can be adopted. The arc-starting function of the rod 32 realizes the arc-starting of the moving contact 3, so that the arc can be better guided to the moving contact arc-starting plate 52, thereby enhancing the arc-extinguishing performance. In practice, the number of arc-starting rods 32 can be 2 to 3, and arc contacts made of arc-resistant conductive materials or arc contacts made of copper materials that are cut integrally with the moving contact 3 are welded at their ends. In this way, when closing the switch, the arc contact at the upper end of the arc-starting rod 32 first contacts the arc-starting plate 511 on the static contact 2, and when opening the switch, it is finally separated from the arc-starting plate 511, playing an arc-starting role and protecting the main contact from being burned. In addition, the arc-starting rods 32 in this embodiment are staggered by 1 to 2 degrees. After multiple connections and disconnections, 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-starting plate 52 is also adopted to facilitate the installation of the moving contact arc-starting plate 52 and to receive the arc at the end of the arc-starting rod 32, specifically as follows: the moving contact arc-starting plate 52 includes a mounting plate 521 and a connecting plate 522, the mounting plate 521 is a square plate structure, and is fixed to the base 1 after bolts pass 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 base 1 to form an arc-connecting end.

[0022] In this embodiment, an insulating cover 7 is installed between the moving contact 3 and the stationary contact 2 to achieve the division of the contact area 11 and the arc extinguishing area 12 between the bottom plate 6 and the base 1, so as to facilitate the mold production of the circuit breaker. Further, the insulating cover 7 is combined with a fixed plate 71 and an isolation plate 72 to facilitate the installation of the insulating cover 7. At the same time, two extension plates are fixed on the side of the isolation plate 72 facing the contact of the stationary contact 2. The two extension plates and the isolation plate 72 form a cavity open to the arc extinguishing area 12, and the cavity accommodates the contact of the stationary contact 2 and the contact row 31, which can effectively avoid the omission of arc when opening and closing the contact between the stationary contact 2 and the contact row 31, and effectively enhance the insulation effect. The insulating cover 7 can always keep the contact of the stationary contact 2 and the contact row 31 in contact. Figure 1 The lower space in the arc chamber is isolated, which prompts the arc to move toward the arc extinguishing chamber and improves the arc extinguishing reliability.

[0023] To sum up, the DC circuit breaker structure of this embodiment can prevent the arc from running into the contact area 11 and burning the static contact 2 and the moving contact 3 by dividing the bottom plate 6 and the base 1 into the contact area 11 and the arc extinguishing area 12. By setting the arc striking plate 5, the distance between the contact area 11 and the arc extinguishing area 12 can be made longer, which can better prevent the arc from running into the contact area 11 and burning the static contact 2 and the moving contact 3.

[0024] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A DC circuit breaker structure, comprising a bottom plate (6), a base (1), a stationary contact (2), a moving contact (3) and an arc extinguishing chamber (4), characterized in that: The base (1) and the bottom plate (6) are spliced ​​to each other on the left and right to form a contact area (11) and an arc extinguishing area (12); the static contact (2) and the moving contact (3) are arranged in the contact area (11); the arc extinguishing chamber (4) is arranged in the arc extinguishing area (12); the static contact (2) is mounted on the bottom plate (6); the moving contact (3) is mounted on the base (1); an arc striking plate (5) is arranged between the contact area (11) and the arc extinguishing area (12); the arc striking plate (5) is arranged on the inner side wall of the base (1), one end of the arc striking plate extends to the contact area (11), and the other end of the arc striking plate extends to the arc extinguishing area (12), so as to guide the arc generated by the static contact (2) and the moving contact (3) into the arc extinguishing chamber (4) in the arc extinguishing area (12) for arc extinguishing.

2. The DC circuit breaker structure according to claim 1, characterized in that: The width of the arc extinguishing zone (12) is greater than the width of the contact zone (11); the side wall of the base (1) is inclined relative to the arc extinguishing zone (12) and the contact zone (11); the arc striking plate (5) comprises a static contact arc striking plate (51) attached to the inner wall of the bottom plate (6) and a dynamic contact arc striking plate (52) attached to the inner wall of the base (1); one end of the static contact arc striking plate (51) extends into the contact zone (11) and is arranged close to the static contact (2); the other end extends to the arc extinguishing zone (12) and is located in the arc extinguishing chamber (4); one end of the dynamic contact arc striking plate (52) extends into the contact zone (11) and is close to the dynamic contact (3) when the dynamic contact (3) is in an open state; the other end extends to the arc extinguishing zone (12) and is located in the arc extinguishing chamber (4).

3. The DC circuit breaker structure according to claim 2, characterized in that: The stationary contact arc-starting plate (51) comprises an arc-starting piece (511) and an insulating plate (512). The insulating plate (512) is installed on the side of the arc-starting piece (511) facing the bottom plate (6), and is bent along with the bending of the arc-starting piece (511), and is extended along the length of the arc-starting piece (511). The insulating plate (512) extends to the stationary contact (2) from one end thereof facing the stationary contact (2), and covers the stationary contact (2), so that only a contact point is exposed on the side of the stationary contact (2) facing the moving contact (3).

4. The DC circuit breaker structure according to claim 3, characterized in that: Two convex ribs (513) arranged side by side with each other are fixed on the side of the insulating plate (512) facing away from the bottom plate (6), and the arc-starting plate (511) is embedded between the two convex ribs (513).

5. The DC circuit breaker structure according to claim 4, characterized in that: The moving contact (3) comprises a contact row (31) and an arc-striking rod (32); the contact point of the stationary contact (2) is a long strip structure; the arc-striking rod (32) is located in the middle of the contact row (31); the end of the arc-striking rod (32) facing away from the contact row (31) is an arc-striking end; when the moving contact (3) is closed, the arc-striking end and the end of the arc-striking plate (511) are close to each other; when the moving contact (3) is opened, the arc-striking end and the end of the moving contact arc-striking plate (52) are close to each other.

6. The DC circuit breaker structure according to claim 5, characterized in that: The moving contact arc-starting plate (52) comprises a mounting plate (521) and a connecting plate (522); the mounting plate (521) is a square plate structure and is fixed to the base (1) 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 base (1) to form an arc-connecting end.

7. The DC circuit breaker structure according to claim 6, characterized in that: An insulating cover (7) is installed between the moving contact (3) and the stationary contact (2), and the insulating cover (7) is located between the contact area (11) and the arc extinguishing area (12), so as to divide the internal space after the base (1) and the bottom plate (6) are assembled into the contact area (11) and the arc extinguishing area (12).

8. The DC circuit breaker structure according to claim 7, characterized in that: The insulating cover (7) comprises a fixing plate (71) and an isolating plate (72), one side of the isolating plate (72) being fixed to the side of the fixing plate (71) so that the insulating cover (7) forms an L-shaped plate structure, and two extension plates are fixed to the side of the isolating plate (72) facing the contact point of the stationary contact (2), and the two extension plates and the isolating plate (72) form a cavity opening toward the arc extinguishing zone (12), and the cavity accommodates the contact point of the stationary contact (2) and the contact row (31) therein.

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