A miniature circuit breaker

Abstract

The utility model relates to a kind of miniature circuit breaker, including shell and be located in electromagnetic system, operating system, thermal tripping system, contact system, arc extinguishing system in shell, the arc extinguishing system includes arc extinguishing chamber, the middle part of the air outlet passage of arc extinguishing chamber bottom is equipped with the partition unit for separating air passage, the shell is sealed by male-female complementary snap structure in the lower side of the air outlet passage.Compared with prior art, the utility model separates air passage into two parts by setting partition unit in air outlet passage, and by using male-female complementary snap structure at the bottom of air outlet passage, the sealing property is guaranteed, and the arc extinguishing efficiency and structural strength are improved. By narrowing the air passage of moving contact side air outlet passage, it is beneficial to enhance the air pressure of this end, so that the gas pushes the arc to move to the other end of the arc extinguishing chamber in the direction of static contact, accelerates arc transfer, and improves arc extinguishing capacity.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, and in particular to a miniature circuit breaker. Background Technology

[0002] With rapid economic development and a significant improvement in people's living standards, society's demand for electrical safety is increasing. As a key protective device in the power system, circuit breakers can not only be installed on terminal distribution lines, but also connect, carry, and disconnect current under normal or abnormal circuit conditions, providing effective protection for lines and electrical equipment.

[0003] To adapt to various application scenarios such as home and industrial control, circuit breakers are gradually developing towards miniaturization. However, due to the compactness of miniaturized design, existing miniature circuit breakers generally suffer from problems such as small opening distance and limited arc-extinguishing chamber volume. This not only restricts their high-voltage breaking capacity, but also further exacerbates the hidden dangers of insufficient arc-extinguishing efficiency and easy contact erosion that already existed in products such as multi-stage series DC circuit breakers, making it difficult to fully meet the current high requirements for electrical safety and equipment reliability. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of insufficient arc extinguishing space in the existing technology and provide a miniature circuit breaker that improves arc extinguishing efficiency and reduces the risk of arc ignition plate ablation.

[0005] The objective of this utility model can be achieved through the following technical solutions:

[0006] A miniature circuit breaker includes a housing and an electromagnetic system, an operating system, a thermal tripping system, a contact system, and an arc extinguishing system disposed within the housing. The arc extinguishing system includes an arc extinguishing chamber, and a partition unit for separating the air passage is provided in the middle of the air outlet passage at the bottom of the arc extinguishing chamber. The housing is sealed on the lower side of the air outlet passage by a male-female complementary interlocking structure.

[0007] Furthermore, the dividing unit is a mechanical connector that connects the housing and divides the air outlet channel into two parts.

[0008] Furthermore, the complementary male and female engaging structure includes: a groove-shaped female part provided on one side of the housing, and a protruding male part provided on the other side of the housing that matches the female part.

[0009] Furthermore, the air outlet channel is narrower at the end closer to the moving contact than at the other end.

[0010] Furthermore, the arc-extinguishing chamber is provided with an arc-inducing plate, which includes two parts that extend radially from the entrance of the arc-extinguishing chamber in a funnel shape to both sides of the arc-extinguishing chamber.

[0011] Furthermore, one part of the arc-inducing piece is located on the stationary contact side and connected to the stationary contact, while the other part is located on the moving contact side and has a U-shaped bending structure at the end near the moving contact.

[0012] Furthermore, the arc-extinguishing chamber is provided with a plurality of arc-extinguishing grid plates arranged at intervals. The arc-extinguishing grid plates are arranged in coordination with the arc-initiating plates, and the size of the grid plates near the entrance of the arc-extinguishing chamber is larger than the size of the grid plates far from the entrance of the arc-extinguishing chamber.

[0013] Furthermore, the arc-extinguishing grid plate of the arc-extinguishing chamber has a notch in the middle.

[0014] Furthermore, the cavity wall on the upper side of the arc-extinguishing grid plate protrudes in the direction of the notch and extends beyond the edge of the notch, so that the arc-inducing plate located at the entrance of the arc-extinguishing chamber is above the notch.

[0015] Furthermore, the arc-extinguishing grid plates in the arc-extinguishing chamber are arranged parallel to the axial direction of the electromagnet in the electromagnetic system.

[0016] Furthermore, deionization units are respectively provided at the air outlets at both ends of the air outlet channel.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. By setting a partition unit in the air outlet channel to divide the air passage into two parts, and by adopting a male-female complementary interlocking structure at the bottom of the air outlet channel, the air tightness and structural strength of the air passage are enhanced, and the arc extinguishing efficiency is improved.

[0019] 2. Since the electric arc is generated near the moving contact end, narrowing the air passage on the corresponding side helps to increase the air pressure at this end, causing the gas to push the electric arc to move towards the other end of the arc-extinguishing chamber in the direction of the stationary contact, accelerating the arc transfer and improving the arc-extinguishing capability.

[0020] 3. The arc-initiating plates are arranged radially in a funnel shape, which is conducive to gas flow and can efficiently and reliably guide the arc from the contact area to the inside of the arc-extinguishing chamber. The length of the arc-extinguishing grid is adjusted according to the arrangement angle of the arc-initiating plates to cooperate with the airflow and enhance the arc-extinguishing capability.

[0021] 4. The thickness of the cavity wall on the upper side of the arc-extinguishing grid extends beyond the edge of the arc-extinguishing grid notch, so that the arc-initiating plate is located above the notch. This prevents the electric arc from establishing a stable arc with the sharp-angled structures at both ends of the middle grid before it moves to the farthest end in the arc-extinguishing chamber, thus ensuring the utilization efficiency of the arc-extinguishing chamber.

[0022] 5. The arc-extinguishing chamber is set along the X direction, and the arc-extinguishing grid is arranged parallel to the axis of the electromagnet of the electromagnetic system. This increases the volume of the arc-extinguishing chamber, which not only meets the requirement of compactness of the miniaturized circuit breaker structure, but also provides more sufficient arc-extinguishing space, avoiding hidden dangers such as insufficient arc-extinguishing efficiency and easy contact erosion. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the miniature circuit breaker in the embodiment;

[0024] Figure 2 This is a schematic diagram of the base-side female component structure of the miniature circuit breaker in the embodiment;

[0025] Figure 3 This is a schematic diagram of the cover-side component structure of the miniature circuit breaker in the embodiment;

[0026] Figure 4 This is a schematic diagram of the unrestricted air passage structure near the stationary contact end outlet in the embodiment.

[0027] Figure 5 This is a schematic diagram of the narrowed air passage structure near the outlet of the moving contact end in the embodiment.

[0028] Figure 6 This is a schematic diagram showing the relative positions of the arc-extinguishing chamber wall and the arc-extinguishing grid in the embodiment.

[0029] Figure label:

[0030] 1-Electromagnetic system; 2-Operating system; 3-Thermal tripping system; 4-Contact system; 5-Arc extinguishing system; 51-First arc ignition plate; 52-Second arc ignition plate; 53-Arc extinguishing chamber; 54-Separation unit; 55-Unrestricted air passage; 56-Restricted air passage; 57-Arc extinguishing grid plate; 58-Notch; 59-De-ionization unit; 6-Housing; 61-Female component; 62-Male component; 63-Cavity wall; 7-Terminal; 8-Air outlet channel. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0032] like Figure 1 As shown, this embodiment proposes a miniature circuit breaker, including a housing 6 and an electromagnetic system 1, an operating system 2, a thermal tripping system 3, a contact system 4, and an arc-extinguishing system 5 disposed within the housing 6. The contact system 4 includes moving contacts and stationary contacts. The arc-extinguishing system 5 includes an arc-extinguishing chamber 53, with an exhaust channel 8 arranged along the X direction at the bottom of the arc-extinguishing chamber 53. A partition unit 54 for separating the exhaust channels is provided in the middle of the exhaust channel 8. The housing 6 is sealed on the lower side of the exhaust channel 8 by a male-female complementary interlocking structure, which enhances the sealing performance and improves the structural strength. Terminals 7 are disposed on both sides of the arc-extinguishing chamber 53 for easy connection to external circuits.

[0033] In this embodiment, the dividing unit 54 is specifically a mechanical connector, which is disposed on the housing 6. While connecting the housing 6, it divides the air outlet channel 8 into two parts, and can be specifically achieved using fixing bolts. Figure 2 As shown, when the bolt holes on the base side and the cover side of the housing 6 are assembled, the bolt hole located in the middle of the air outlet channel 8 separates the air outlet channel 8 into two parts, which improves the arc extinguishing efficiency and enhances the air tightness and structural strength of the air channel.

[0034] The arc-extinguishing chamber 53 is arranged along the X direction. Specifically, the arc-extinguishing grid plates 57 of the arc-extinguishing chamber 53 are arranged in a direction parallel to the axis of the electromagnet of the electromagnetic system 1, which increases the volume of the arc-extinguishing chamber 53. This not only meets the requirement of compactness of the miniaturized circuit breaker structure, but also provides more arc-extinguishing space, avoiding potential hazards such as insufficient arc-extinguishing efficiency and easy contact erosion.

[0035] When the moving and stationary contacts of a circuit breaker separate, an electric arc is initially generated between the contacts. If the arc cannot quickly leave the contact area and enter the arc-extinguishing grid 57, it will burn the contacts for a long time, leading to severe contact burn-out and reducing the life of the circuit breaker. The arc-extinguishing chamber 53 is equipped with arc-initiating plates, which include two parts extending radially from the entrance of the arc-extinguishing chamber 53 in a funnel shape to both sides of the arc-extinguishing chamber 53, with an arc-blocking plate with insulating gas-generating function arranged between them. The funnel-shaped arc-initiating plates form a smooth transition channel radiating outward from the center of the contact, which can efficiently and reliably guide the arc from the contact area to the interior of the arc-extinguishing chamber 53, ensuring that the arc can be successfully divided and extinguished, while minimizing contact erosion. The first arc-initiating plate 51 is located on the stationary contact side and connected to the stationary contact. The first arc-initiating plate 51 extends at an angle to the X direction, bends to one side of the arc-extinguishing chamber 53, and is parallel to the arc-extinguishing grid 57. The second arc-starting piece 52 is disposed on one side of the moving contact, and adopts a U-shaped bending structure at the end near the moving contact. This structure has higher mechanical strength and rigidity, ensuring rapid transfer of the arc root, protecting the main contact, providing better electromagnetic driving force, extending the arc path, accelerating cooling and arc extinguishing, and enhancing mechanical strength and ablation resistance. Compared with the first arc-starting piece 51, the second arc-starting piece 52 extends shorter in the X direction, and bends to the other side of the arc-extinguishing chamber 53, parallel to the arc-extinguishing grid piece 57.

[0036] like Figure 2 , Figure 3As shown, the complementary male-female locking structure in this embodiment includes: a groove-shaped female part 61 located on the base side of the housing 6, and a protruding male part 62 located on the cover side of the housing 6 that matches the female part 61. The female part 61 and the male part 62, as part of the housing 6, seal the air outlet channel 8. In specific implementations, the groove cross-sectional shape of the female part 61 can be rectangular, trapezoidal, mushroom-shaped, etc., and the cross-sectional shape of the male part 62 matches the groove shape of the female part 61. During installation, the two parts will lock together, forming a physical barrier, ensuring airtightness while improving structural strength. In this embodiment, the groove cross-sectional shape of the female part 61 is rectangular, and the locking structure is connected by fixing bolts.

[0037] The air outlet channel 8 is narrower at the end closer to the moving contact compared to the other end. In this embodiment, as... Figure 4 As shown, the outlet of the air passage 8 is configured as a narrowed air passage 56 at the end closer to the moving contact, such as... Figure 5 As shown, the air passage at the outlet closer to the stationary contact is an unrestricted air passage 55, remaining unobstructed. The narrowed air passage 56 is constructed by providing arc-shaped structures protruding towards the air passage axis on both the upper and lower sides of the air passage, thus narrowing the air passage. The air passage at the moving contact end is narrowed, while the air passage at the stationary contact end is not narrowed, which serves to regulate airflow: since the electric arc is generated near the moving contact end, the narrowing of the air passage at the moving contact end helps to increase the air pressure at this end, causing the gas to push the electric arc towards the other end of the arc-extinguishing chamber 53 in the direction of the stationary contact, accelerating the arc transfer and improving the arc-extinguishing capability. In actual implementation, other structural designs can be adopted, such as enlarging the air passage at the outlet closer to the stationary contact end to increase the air pressure at the moving contact end, which also serves to regulate airflow.

[0038] The arc-extinguishing chamber 53 is equipped with multiple arc-extinguishing grid plates 57 arranged at intervals. The arc-extinguishing grid plates 57 are arranged in conjunction with the arc-initiating plates. The size of the grid plates 57 near the entrance of the arc-extinguishing chamber 53 is larger than that far from the entrance of the arc-extinguishing chamber 53. This allows for gradual control of the electric arc, optimizes the airflow field and pressure distribution, and thus extinguishes the electric arc more smoothly and efficiently. At the same time, it can make better use of space, make reasonable layout, and improve arc-extinguishing efficiency.

[0039] like Figure 6As shown, in this embodiment, the arc-extinguishing grid 57 has a notch 58 in the middle. The notch 58 is U-shaped or V-shaped, and the two sides of the notch 58 have similar pointed structures, which helps to further lengthen the arc and make it have a larger contact area with the arc-extinguishing grid 57, thereby better cooling the arc. In this embodiment, by thickening the cavity wall 63 on the upper side of the arc-extinguishing grid 57, making it protrude towards the location of the notch 58 and extend beyond the edge of the notch 58 of the arc-extinguishing grid 57, as shown by the red dotted circle, the arc-starting plate is limited to the area directly opposite the notch 58, as shown by the red arrow. This can prevent the arc from establishing a stable arc with the pointed structures at both ends of the middle grid before it moves to the farthest end in the arc-extinguishing chamber 53, thus ensuring the utilization efficiency of the arc-extinguishing chamber 53.

[0040] At each end of the air outlet of the air outlet channel 8, an anti-ionization unit 59 is provided. In this embodiment, the anti-ionization unit 59 has a porous structure. Figure 4 As shown, the deionization unit 59 near the air outlet at the stationary contact end has a double-layer porous structure. For example... Figure 5 As shown, due to the narrowing of the air passage near the moving contact end, a larger airflow is required. Therefore, the de-ionization unit 59, located in front of the narrowed air passage 56, is a single-layer porous structure. The porous structure of the de-ionization unit 59 increases the arc creepage path and distance, and can further utilize the near-electrode voltage drop to extinguish the arc, thereby achieving the purpose of suppressing the arc.

[0041] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0043] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0044] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0045] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0046] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A miniature circuit breaker, characterized in that, The system includes a housing (6) and an electromagnetic system (1), an operating system (2), a thermal tripping system (3), a contact system (4), and an arc extinguishing system (5) disposed in the housing (6). The arc extinguishing system (5) includes an arc extinguishing chamber (53). A partition unit (54) for separating the air passage is provided in the middle of the air outlet passage (8) at the bottom of the arc extinguishing chamber (53). The housing (6) is sealed on the lower side of the air outlet passage (8) by a male-female complementary snap-fit ​​structure.

2. The miniature circuit breaker according to claim 1, characterized in that, The dividing unit (54) is a mechanical connector that connects the housing (6) and divides the air outlet channel (8) into two parts.

3. A miniature circuit breaker according to claim 1, characterized in that, The complementary male and female engaging structure includes: a grooved female part (61) provided on one side of the housing (6), and a protruding male part (62) provided on the other side of the housing (6) that matches the female part (61).

4. A miniature circuit breaker according to claim 1, characterized in that, The air outlet channel (8) is narrower at the end closer to the moving contact than at the other end.

5. A miniature circuit breaker according to claim 1, characterized in that, The arc-extinguishing chamber (53) is provided with an arc-inducing plate, which includes two parts that extend radially from the entrance of the arc-extinguishing chamber (53) in a funnel shape to both sides of the arc-extinguishing chamber (53).

6. A miniature circuit breaker according to claim 5, characterized in that, One part of the arc-inducing plate is located on the stationary contact side and connected to the stationary contact, while the other part is located on the moving contact side and has a U-shaped bending structure at the end near the moving contact.

7. A miniature circuit breaker according to claim 5, characterized in that, The arc-extinguishing chamber (53) is provided with a plurality of arc-extinguishing grid plates (57) arranged at intervals. The arc-extinguishing grid plates (57) are arranged in coordination with the arc-inducing plates, and the size of the grid plates (57) near the entrance of the arc-extinguishing chamber (53) is larger than the size of the grid plates far from the entrance of the arc-extinguishing chamber (53).

8. A miniature circuit breaker according to claim 1 or 7, characterized in that, The arc-extinguishing grid plate (57) of the arc-extinguishing chamber (53) has a notch (58) in the middle.

9. A miniature circuit breaker according to claim 8, characterized in that, The cavity wall (63) on the upper side of the arc-extinguishing grid plate (57) protrudes in the direction of the notch (58) and extends beyond the edge of the notch (58), so that the arc-inducing plate located at the entrance of the arc-extinguishing chamber (53) is above the notch (58).

10. A miniature circuit breaker according to claim 1, characterized in that, The arc-extinguishing grid plates (57) of the arc-extinguishing chamber (53) are arranged in a direction parallel to the axis of the electromagnet of the electromagnetic system (1).

11. A miniature circuit breaker according to claim 1, characterized in that, The air outlets at both ends of the air outlet channel (8) are respectively provided with deionization units (59).

Images