Switch unit and miniature circuit breaker comprising same

Abstract

The utility model relates to a switch unit and a miniature circuit breaker comprising the switch unit, which belong to the technical field of circuit breakers, and comprise an arc extinguishing system, the arc extinguishing system comprises an arc extinguishing chamber, a static contact arc striking guide rail arranged at one end of the arc extinguishing chamber, and a moving contact arc striking guide rail arranged at the other end of the arc extinguishing chamber, the two sides of the arc extinguish chamber are respectively provided with an arc extinguish chamber side plate, a plurality of arc extinguish sheets which are sequentially arranged at intervals are arranged between the two arc extinguish chamber side plates, the arc extinguish sheets are provided with arc extinguish sheet front edges, and the arc extinguish chamber side plates are provided with side plate front edge inner grooves used for wrapping the arc extinguish sheet front edges. According to the utility model, the front edge of the arc extinguishing sheet is wrapped and isolated by the inner groove at the front edge of the side plate, so that the arc striking sheet and the arc extinguishing sheet can be prevented from jumping in advance, the front edge of the arc extinguishing sheet is insulated, the arc extinguishing sheet and the side plate of the arc extinguishing chamber are integrated, gas production and insulation are provided, and the assembly is simple.

Description

Technical Field

[0001] The utility model belongs to the technical field of circuit breakers, and in particular relates to the layout design of an arc extinguishing system of a circuit breaker. Background Art

[0002] Generally speaking, the overall structure of a traditional miniature circuit breaker is mainly divided into an operating mechanism, a contact system, a terminal system, a thermal trip system, a magnetic trip system, and an arc extinguishing system. Typically, a small DC circuit breaker uses multiple single-stage circuit breakers connected in series to form a multi-stage modular circuit breaker. This circuit breaker has a higher overall rated voltage and is widely used in the market.

[0003] The arc extinguishing chamber of a circuit breaker is a crucial component of the arc extinguishing system. During interruption, as the concentration of conductive particles and temperature within the chamber increase, the tips of the arc extinguishing plates in traditional arc extinguishing chambers may connect to the arc starting plates, initiating an arc. This results in partial unutilization of the arc extinguishing chamber, reducing arc extinguishing efficiency and even leading to interruption failure. Specifically, the proximity of the arc extinguishing plate tips to the arc starting plates can lead to premature arcing, resulting in incomplete utilization of the arc extinguishing chamber.

[0004] In addition, in addition to being used individually, miniature circuit breakers are often used in series in 2P, 3P, and other configurations to increase arc extinguishing capacity. Each circuit breaker often has both thermal and magnetic tripping mechanisms. The simultaneous presence of thermal and magnetic tripping mechanisms is necessary when using a single miniature circuit breaker. However, when multi-pole miniature circuit breakers are connected in series, the thermal and magnetic tripping mechanisms become redundant, resulting in insufficient utilization of the arc extinguishing space. Utility Model Content

[0005] The purpose of the utility model is to provide a switch unit and a miniature circuit breaker including the switch unit, so as to solve the problems existing in the background technology.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present invention provides a switch unit, including an arc extinguishing system, the arc extinguishing system including an arc extinguishing chamber, a static contact arc striking guide rail arranged at one end of the arc extinguishing chamber, and a moving contact arc striking guide rail arranged at the other end of the arc extinguishing chamber, arc extinguishing chamber side plates are respectively provided on both sides of the arc extinguishing chamber, and a plurality of arc extinguishing plates arranged in sequence and spaced apart are provided between the two arc extinguishing chamber side plates, the arc extinguishing plates are provided with arc extinguishing plate front edges, and the arc extinguishing chamber side plates are provided with side plate front edge inner grooves for wrapping the front edges of the arc extinguishing plates.

[0007] Preferably, arc-extinguishing plate protrusions are provided on both sides of the arc-extinguishing plate, and the arc-extinguishing chamber side plates are provided with side plate mounting holes that can cooperate with the arc-extinguishing plate protrusions.

[0008] Preferably, a plurality of side plate inner ribs that can guide the installation of the arc extinguishing pieces are provided on the inner side of the arc extinguishing chamber side plate.

[0009] Preferably, it includes an operating mechanism, a terminal block, the arc extinguishing system, and also includes a magnetic tripping system or a thermal tripping system.

[0010] The technical solution of the present utility model further provides a miniature circuit breaker, comprising two or more switch units, wherein one of the two switch units is provided with the magnetic tripping system, and the other is provided with the thermal tripping system.

[0011] In summary, the present invention has the following beneficial technical effects:

[0012] In an arc extinguishing system with at least two poles of miniature circuit breakers connected in series, the magnetic tripping system in one pole and the thermal tripping system in the other pole are removed, and only the magnetic tripping system and the thermal tripping system are ensured to be respectively in one pole. The saved space is increased as space for the arc extinguishing system, thereby increasing the arc extinguishing capacity, improving the breaking capacity of the system, reducing production costs, improving insulation performance, and at the same time enhancing gas production performance, taking into account installability.

[0013] A series arc extinguishing system only requires one magnetic trip and one thermal trip, which reduces production costs by eliminating redundant arc extinguishing mechanisms. The arc extinguishing performance of the series arc extinguishing system is improved by increasing the arc extinguishing capacity.

[0014] The front edge of the arc extinguishing plate is wrapped and isolated by the inner groove of the front edge of the side plate, which is beneficial to avoid premature arcing between the arc-starting plate and the arc extinguishing plate, and insulates the front edge of the arc extinguishing plate. The arc extinguishing plate is integrated with the side plate of the arc extinguishing chamber, and gas production and insulation are provided at the same time, which is simple to assemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the main view of a traditional circuit breaker;

[0016] Figure 2 Schematic diagram comparing embodiment 1 of the present utility model with a conventional circuit breaker;

[0017] Figure 3 Schematic diagram comparing embodiment 2 of the present utility model with a conventional circuit breaker;

[0018] Figure 4 This is a schematic diagram of the arc extinguishing principle of Example 1 of the present utility model;

[0019] Figure 5 This is a schematic diagram of the arc extinguishing principle of Example 2 of the present utility model;

[0020] Figure 6 Schematic diagram comparing the arc extinguishing chamber in Example 3 of the present invention with a traditional arc extinguishing chamber;

[0021] Figure 7 Schematic diagram comparing the arc path of the arc extinguishing chamber in Example 3 of the present invention and the arc path of the traditional arc extinguishing chamber;

[0022] Figure 8 This is a schematic diagram of the arc extinguishing chamber structure in Example 3 of the present utility model;

[0023] Figure 9 Schematic diagram of the arc extinguishing chamber structure installation in Example 3 of the present utility model Figure 1 ;

[0024] Figure 10 Schematic diagram of the arc extinguishing chamber structure installation in Example 3 of the present utility model Figure 2 ;

[0025] Figure 11 This is a schematic diagram of miniature circuit breakers in series in Example 4 of the present utility model;

[0026] Figure 12 This is an axonometric view of the magnetic trip pole in Example 4 of the present utility model;

[0027] Figure 13 This is a cross-sectional view from the perspective of the magnetic trip pole in Example 4 of the present utility model;

[0028] Figure 14 This is an axonometric view of the thermal tripping perspective in Example 4 of the present utility model;

[0029] Figure 15 This is a cross-sectional view from the thermal tripping perspective in Example 4 of the present utility model;

[0030] Figure 16 This is a schematic diagram of the arc extinguishing principle of Example 5 of the present utility model.

[0031] Figure numerals: 1. Arc extinguishing system; 11. Arc extinguishing chamber; 12. Arc extinguishing chamber side panel; 121. Inner groove of the front edge of the side panel; 122. Side panel mounting hole; 123. Inner rib of the side panel; 13. Arc extinguishing plate; 131. Front edge of the arc extinguishing plate; 132. Arc extinguishing plate protrusion; 14. Arc striking guide rail of static contact; 15. Arc striking guide rail of moving contact; 2. Contact system; 21. Moving contact; 22. Static contact; 3. Terminal block; 4. Thermal trip system; 41. Connecting rod; 42. Thermal bimetallic strip; 5. Magnetic trip system; 6. Operating mechanism; 61. Operating handle; 62. Lock; 63. Buckle; 7. Y-type equipotential arc striking plate. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] Example 1:

[0034] The present invention discloses a miniature circuit breaker comprising an arc extinguishing system 1, an operating mechanism 6, a contact system 2, terminal blocks 3, and a thermal trip system 4. This miniature circuit breaker differs from conventional miniature circuit breakers in that the magnetic trip system 5 is omitted, thereby increasing the capacity of the arc extinguishing chamber 11. Specifically, compared to conventional miniature circuit breakers, the magnetic trip system 5 is omitted, and the resulting space is used to expand the capacity of the arc extinguishing chamber 11. This increases the arc extinguishing capability of the arc extinguishing system 1 and enhances its performance.

[0035] The operating mechanism 6 includes an operating handle 61, a lock 62, and a buckle 63; the thermal trip system 4 includes a connecting rod 41 and a thermal bimetallic strip 42; when the current is overloaded for a certain period of time, the thermal bimetallic strip 42 drives the connecting rod 41 through deformation, and then pulls the buckle 63 to realize the unlocking of the lock 62 and the buckle 63, thereby realizing the tripping of the circuit breaker. The arc generated between the moving contact 21 and the static contact 22 enters the arc extinguishing chamber 11 through the moving contact arc striking guide rail 15 and the static contact arc striking guide rail 14 and realizes the arc extinguishing.

[0036] Example 2:

[0037] The present invention discloses a miniature circuit breaker comprising an arc extinguishing system 1, an operating mechanism 6, a contact system 2, terminal blocks 3, and a magnetic tripping system 5. This miniature circuit breaker differs from conventional miniature circuit breakers in that the thermal tripping system 4 is omitted, thereby increasing the capacity of the arc extinguishing chamber 11. Specifically, compared to conventional miniature circuit breakers, the thermal tripping system 4 is omitted, and the resulting space is used to expand the capacity of the arc extinguishing chamber 11, thereby increasing the arc extinguishing capability of the arc extinguishing system 1 and improving performance.

[0038] Example 3:

[0039] This embodiment discloses a miniature circuit breaker, which is a further improvement based on the first or second embodiment.

[0040] The miniature circuit breaker of this embodiment includes an arc extinguishing system 1. The arc extinguishing system 1 comprises an arc extinguishing chamber 11, a static contact arc-striking guide 14 located at one end of the arc extinguishing chamber 11, and a movable contact arc-striking guide 15 located at the other end of the arc extinguishing chamber 11. The static contact arc-striking guide 14 connects to the static contact 22, while the movable contact arc-striking guide 15 connects to the movable contact 21. Two spaced-apart arc extinguishing chamber side panels 12 are located on either side of the arc extinguishing chamber 11. Multiple arc extinguishing plates 13 are distributed between the two vertically arranged arc extinguishing chamber side panels 12, with intervals between the multiple arc extinguishing plates 13.

[0041] In this embodiment, arc-extinguishing plate leading edges 131 are distributed on the left and right sides of the front end of the arc-extinguishing plate 13, and the arc-extinguishing chamber side panels 12 located on both sides of the arc-extinguishing plate 13 are provided with side panel leading edge inner grooves 121 for wrapping the arc-extinguishing plate leading edges 131; arc-extinguishing plate protrusions 132 are provided on the left and right sides of the arc-extinguishing plate 13, and the arc-extinguishing chamber side panels 12 are provided with side panel mounting holes 122 that can be plugged in and matched with the arc-extinguishing plate protrusions 132 to complete the fixation; in addition, the inner side of the arc-extinguishing chamber side panels 12 are also provided with a plurality of side panel inner ribs 123 that can guide the installation of the arc-extinguishing plate 13.

[0042] When installing the arc-extinguishing chamber side plate 12 and arc-extinguishing plate 13, first insert the arc-extinguishing plate leading edge 131 along the inner groove 121 of the side plate leading edge into the arc-extinguishing chamber side plate 12. Then, snap the arc-extinguishing plate protrusion 132 into the side plate installation hole 122 reserved in the arc-extinguishing chamber side plate 12. The arc-extinguishing chamber side plate 12 on the other side of the arc-extinguishing plate 13 is installed in the same manner. In this way, multiple arc-extinguishing plates 13 are combined with the two arc-extinguishing chamber side plates 12 into one body, and the arc-extinguishing plate leading edge 131 is wrapped around it.

[0043] In this embodiment, the inner groove 121 at the front edge of the side plate wraps around and isolates the leading edge 131 of the arc extinguishing plate, thereby preventing premature arcing between the arc-striking plate (stationary contact arc-striking guide 14 / moving contact arc-striking guide 15) and the arc-striking plate 13. Furthermore, the resulting structure has the following advantages: 1. The leading edge 131 of the arc extinguishing plate is insulated; 2. The arc extinguishing plate 13 is integrated with the arc-extinguishing chamber side plate 12, providing both gas generation and insulation; and 3. It is easy to assemble.

[0044] Example 4:

[0045] This embodiment discloses a miniature circuit breaker, taking a two-pole miniature circuit breaker product as an example, the series connection method is shown in the attached Figure 11 One of them adopts the miniature circuit breaker of embodiment 1 or embodiment 3 improved on the basis of embodiment 1, and the other adopts the miniature circuit breaker of embodiment 2 or embodiment 3 improved on the basis of embodiment 2.

[0046] In this embodiment, the magnetic trip system 5 in one pole and the thermal trip system 4 in the other pole are removed, ensuring that only the magnetic trip system 5 and the thermal trip system 4 are respectively provided on one pole. The saved space is increased to provide space for the arc extinguishing system 1, thereby increasing the arc extinguishing capacity, improving the system's breaking capacity, and reducing production costs.

[0047] Example 5:

[0048] This embodiment discloses a novel magnetic trip arc extinguishing solution. Specifically, to further increase the arc extinguishing chamber capacity in the magnetic pole arc extinguishing solution, the arc extinguishing chamber can be arranged symmetrically, with gas outlets in both left and right directions. Compared to the above L-shaped grid arrangement, its advantages are:

[0049] 1. Increasing the number of grid arrangements provides a material basis for improving the arc extinguishing capacity of the magnetic pole and the arc extinguishing performance of the miniature circuit breaker;

[0050] 2. The symmetrical layout of the arc extinguishing chambers ensures balanced gas discharge from the arc extinguishing chambers on both sides, making full use of the grids in the arc extinguishing chambers on the left and right sides. Being able to make full use of each grid is the key to improving the arc extinguishing performance of the circuit breaker.

[0051] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A switch unit, characterized in that: The invention comprises an arc extinguishing system (1), wherein the arc extinguishing system (1) comprises an arc extinguishing chamber (11), a static contact arc striking guide rail (14) provided at one end of the arc extinguishing chamber (11), and a moving contact arc striking guide rail (15) provided at the other end of the arc extinguishing chamber (11); arc extinguishing chamber side plates (12) are respectively provided on both sides of the arc extinguishing chamber (11); a plurality of arc extinguishing plates (13) arranged in sequence and spaced apart are provided between the two arc extinguishing chamber side plates (12); the arc extinguishing plates (13) are provided with arc extinguishing plate front edges (131); and the arc extinguishing chamber side plates (12) are provided with side plate front edge inner grooves (121) for wrapping the arc extinguishing plate front edges (131).

2. A switch unit according to claim 1, characterized in that: Arc extinguishing piece protrusions (132) are provided on both sides of the arc extinguishing piece (13), and the arc extinguishing chamber side plate (12) is provided with a side plate mounting hole (122) that can cooperate with the arc extinguishing piece protrusions (132).

3. The switch unit according to claim 1, characterized in that: A plurality of side plate inner ribs (123) capable of guiding the installation of the arc extinguishing pieces (13) are provided on the inner side of the arc extinguishing chamber side plate (12).

4. A switch unit according to any one of claims 1 to 3, characterized in that: It comprises an operating mechanism (6), a connecting terminal (3), the arc extinguishing system (1), and also comprises one of a magnetic tripping system (5) or a thermal tripping system (4).

5. A miniature circuit breaker, characterized in that: The switch unit comprises at least two switch units according to claim 4, wherein one is provided with only the magnetic tripping system (5), and the other is provided with only the thermal tripping system (4).

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