Arc grid and arc extinguishing mechanism comprising same

Abstract

Disclosed are an arc grid and an arc extinguishing mechanism comprising same. According to an aspect of the present invention, the arc grid comprises: a plate-shaped arc grid body; a pair of arc grid racks extending from one end portion of the arc grid body in the height direction; a pair of arc grid outer circumferences forming inside corners of the pair of arc grid racks, respectively; and an arc grid recess which is located between the pair of arc grid racks, and is recessed at one end portion of the arc grid body, wherein the pair of arc grid outer circumferences obliquely extend so as to have certain angles with respect to the height direction of the arc grid body and to face the arc grid recess and each other, and the end portion of the arc grid recess in the height direction may be located higher than one point where extensions from the pair of the arc grid outer circumferences cross each other.

Description

Arc grid and arc extinguishing device including the same

[0001] The present invention relates to an arc grid and an arc extinguishing mechanism including the same, and more specifically, to an arc grid having a structure in which the arc can be sufficiently extended even in the case of a small current, and an arc extinguishing mechanism including the same.

[0002] A circuit breaker is installed in a power system and connected to the power source and the load, respectively, to enable current flow. If an abnormal current occurs between the power source and the load, the circuit breaker performs a tripping operation to interrupt the current flow between them. As a result, the power source and the load can be protected from damage caused by the abnormal current.

[0003] Typically, a circuit breaker includes a fixed contact that is fixedly installed and a movable contact that is movably provided. The movable contact is provided to be movable in a direction toward the fixed contact or in a direction opposite to the fixed contact. When the movable contact is in contact with the fixed contact, the power source and the load can be energized to each other. In the event of an abnormal current, the movable contact separates from the fixed contact, and the energization of the power source and the load is released.

[0004] Even at the moment when the movable contact and the fixed contact separate, the current—specifically the abnormal current—continues to flow through them. Therefore, when the movable contact and the fixed contact separate, the energy of the current being conducted is converted into a flow of electrons at high temperature and high pressure. This converted flow of electrons is called an arc.

[0005] As mentioned above, an arc is a flow of electrons at high temperature and high pressure. Therefore, if the arc remains inside the circuit breaker instead of being discharged to the outside, there is a risk that other components of the breaker may be damaged by the heat or pressure of the arc. Accordingly, a process is required to discharge the generated arc to the outside while reducing its temperature and pressure; this is called the arc extinguishing process.

[0006] For arc extinguishment, the arc must be extended sufficiently and rapidly. Furthermore, the extended arc must be able to be divided into short arcs (typically referred to as short arcs) and discharged externally. To this end, circuit breakers are generally equipped with an arc extinguishing mechanism comprising multiple grids.

[0007] In this case, if the power flowing through the circuit breaker is high voltage and low current, it is difficult for the arc generated due to the low current value to sufficiently extend toward the grid. Furthermore, if additional components are provided to sufficiently extend the arc, the physical structure of the space where the arc occurs must be altered, which may require a change in the overall design.

[0008] Accordingly, a method is required to rapidly extend the arc by changing only the structure of the grid itself.

[0009] Korean Published Patent Document No. 10-2023-0109443 discloses an arc extinguishing section of a circuit breaker. Specifically, it discloses an arc extinguishing section of a circuit breaker that includes a plurality of insulating members coupled to a plurality of grids, capable of directing a generated arc in a desired direction among the parts of the grids.

[0010] However, the arc extinguishing section disclosed in the aforementioned prior art requires a separate insulating member. In other words, the prior art does not provide a method to improve the arc elongation force by modifying the structure of the grid itself without adding components.

[0011] Korean Registered Patent Document No. 10-2542180 discloses an arc extinguishing device for a DC circuit breaker. Specifically, it discloses an arc extinguishing device capable of guiding a generated arc toward a grid by installing electromagnets and suction rods at both ends of a plurality of grids.

[0012] However, the aforementioned prior art also requires additional components, such as an electromagnet and a suction rod, for arc induction. In other words, the prior art also fails to provide a method to improve the arc elongation force by modifying the structure of the grid itself without adding components.

[0013] Korean Published Patent Document No. 10-2023-0109443 (July 20, 2023)

[0014] Korean Registered Patent Document No. 10-2542180 (June 7, 2023)

[0015] The present invention aims to solve the aforementioned problems, and the objective of the present invention is to provide an arc grid with a structure capable of sufficiently extending the arc even in a high-voltage, low-current environment, and an arc extinguishing mechanism including the same.

[0016] Another objective of the present invention is to provide an arc grid with a structure capable of sufficiently extending an arc without adding components, and an arc extinguishing mechanism including the same.

[0017] Another objective of the present invention is to provide an arc grid with a structure capable of sufficiently extending the arc solely by changing the structure of the grid, and an arc extinguishing mechanism including the same.

[0018] Another objective of the present invention is to provide an arc grid having a structure capable of guiding a generated arc in a desired direction, and an arc extinguishing mechanism including the same.

[0019] Another objective of the present invention is to provide an arc grid with a structure capable of maintaining or enhancing the cooling effect of a generated arc, and an arc extinguishing mechanism including the same.

[0020] The problems of the present invention are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art to which the present invention pertains from the description below.

[0021] According to one aspect of the present invention, an arc grid is provided, comprising: a plate-shaped arc grid body; a pair of arc grid racks extending from one end in the height direction of the arc grid body; a pair of arc grid outer circumferences forming the inner corners of each of the pair of arc grid racks; and an arc grid groove positioned between the pair of arc grid racks and formed by being recessed at one end of the arc grid body, wherein the pair of arc grid outer circumferences extend obliquely toward the arc grid grooves and toward each other at a predetermined angle with respect to the height direction of the arc grid body, and the end of the arc grid groove in the height direction is positioned higher than a point where the extension lines of the pair of arc grid outer circumferences meet.

[0022] At this time, an arc grid may be provided, wherein the arc grid rack comprises: a first arc grid rack located on one side in the longitudinal direction of the arc grid body; and a second arc grid rack located on the other side in the longitudinal direction of the arc grid body, and the arc grid outer circumference comprises: a first arc grid outer circumference that forms an inner corner of the first arc grid rack and extends obliquely toward the arc grid groove; and a second arc grid outer circumference that forms an inner corner of the second arc grid rack and extends obliquely toward the arc grid groove.

[0023] Additionally, an arc grid may be provided, which includes an arc grid inner circumference defined as an inner corner of the arc grid body and partially surrounding the arc grid groove, and has an outwardly protruding projection formed at a continuous portion where the arc grid inner circumference and the arc grid outer circumference are connected.

[0024] At this time, an arc grid may be provided, comprising: a first arc grid inner circumference that extends in the height direction of the arc grid body, is continuous with the arc grid outer circumference, and surrounds the arc grid groove on one side in the width direction; a second arc grid inner circumference that extends in the height direction of the arc grid body, is continuous with the arc grid outer circumference, and surrounds the arc grid groove on the other side in the width direction; and a third arc grid inner circumference that is continuous with the first arc grid inner circumference and the second arc grid inner circumference, respectively, and surrounds the end of the arc grid groove.

[0025] Additionally, an arc grid may be provided at the point where the extension lines of the outer circumference of a pair of arc grids meet, which is located between the projection and the inner circumference of the third arc grid along the height direction of the arc grid body.

[0026] At this time, the point where the extension lines of the outer circumference of the pair of arc grids meet may be provided with an arc grid located on the inner circumference of the first arc grid.

[0027] Additionally, according to one aspect of the present invention, an arc extinguishing mechanism may be provided, comprising: a plurality of arc grids formed in a plate shape and spaced apart and arranged in parallel along the thickness direction; an arc extinguishing frame coupled to one side in the height direction of the plurality of arc grids; and an arc guide coupled to the other side in the height direction of the plurality of arc grids, wherein the arc grids comprise: a plate-shaped arc grid body; a pair of arc grid racks extending from one end in the height direction of the arc grid body; and an arc grid groove positioned between the pair of arc grid racks and formed by being recessed in the one end of the arc grid body, wherein the end in the height direction of the arc grid groove is positioned higher than a point where the extension lines of the inner edges of the pair of arc grid racks meet.

[0028] At this time, an arc extinguishing mechanism may be provided, wherein the arc guide comprises a first arc guide located on one side of the separation direction; and a second arc guide located on the other side of the separation direction, wherein the height of the first arc guide is formed to be longer than the height of the second arc guide.

[0029] Additionally, the arc guide may be provided with an arc extinguishing mechanism comprising: a pair of arc grid outer circumferences constituting the corners of a pair of arc grid racks; and an arc grid inner circumference surrounding the arc grid groove and continuous with the arc grid outer circumference, wherein one end of the arc grid inner circumference in the height direction is positioned higher than the point where the extension lines of the pair of arc grid inner circumferences meet.

[0030] At this time, an arc extinguishing mechanism may be provided, comprising: a first arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on one side in the width direction; a second arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on the other side in the width direction; and a third arc grid inner circumference that is continuous with the first arc grid inner circumference and the second arc grid inner circumference, respectively, and surrounding the end of the arc grid groove.

[0031] Additionally, at the point where the extension lines of a pair of the inner circumferences of the arc grid meet, an arc extinguishing mechanism may be provided, which is located on the inner circumference of the first arc grid.

[0032] At this time, an arc extinguishing mechanism may be provided, wherein the arc grid rack comprises: a first arc grid rack located on one side in the longitudinal direction of the arc grid body; and a second arc grid rack located on the other side in the longitudinal direction of the arc grid body, and the arc grid outer circumference comprises: a first arc grid outer circumference that forms an inner edge of the first arc grid rack and extends obliquely toward the arc grid groove; and a second arc grid outer circumference that forms an inner edge of the second arc grid rack and extends obliquely toward the arc grid groove.

[0033] Additionally, an arc extinguishing mechanism may be provided in which the portion where the outer circumference of the first arc grid and the inner circumference of the first arc grid are continuous is positioned higher than the portion where the outer circumference of the second arc grid and the inner circumference of the second arc grid are continuous.

[0034] According to the above configuration, the arc grid and the arc extinguishing mechanism including the same according to the embodiment of the present invention can sufficiently extend the arc even in a high-voltage, low-current environment.

[0035] In addition, according to the above configuration, the arc grid and the arc extinguishing mechanism including the same according to the embodiment of the present invention can sufficiently extend the arc without adding any configuration.

[0036] In addition, according to the above configuration, the arc grid and the arc extinguishing mechanism including the same according to the embodiment of the present invention can sufficiently extend the arc by only changing the structure of the grid.

[0037] In addition, according to the above configuration, the arc grid and the arc extinguishing mechanism including the same according to the embodiment of the present invention can guide the generated arc in a desired direction.

[0038] In addition, according to the above configuration, the arc grid and the arc extinguishing mechanism including the same according to the embodiment of the present invention can maintain or enhance the cooling effect of the generated arc.

[0039] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

[0040] FIG. 1 is a perspective view illustrating an arc extinguishing mechanism according to an embodiment of the present invention.

[0041] Figure 2 is a front view illustrating the arc extinguishing mechanism of Figure 1.

[0042] Fig. 3 is a rear view illustrating the arc extinguishing mechanism of Fig. 1.

[0043] Figure 4 is a bottom view illustrating the arc extinguishing mechanism of Figure 1.

[0044] Fig. 5 is an exploded perspective view illustrating the arc extinguishing mechanism of Fig. 1.

[0045] FIG. 6 is a front view illustrating a first arc grid according to one embodiment of the present invention.

[0046] FIG. 7 is a front view illustrating a second arc grid according to one embodiment of the present invention.

[0047] FIG. 8 is a front view illustrating a first arc grid according to another embodiment of the present invention.

[0048] FIG. 9 is a front view illustrating a second arc grid according to another embodiment of the present invention.

[0049] FIGS. 10 and 11 are a front view (Fig. 10) and a rear view (Fig. 11) of first arc grids overlaid according to one embodiment and another embodiment of the present invention.

[0050] FIGS. 12 and 13 are a front view (Fig. 12) and a rear view (Fig. 13) of second arc grids overlapping according to one embodiment and another embodiment of the present invention.

[0051] Hereinafter, embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms and is not limited to the embodiments described herein. To clearly explain the present invention, parts unrelated to the description in the drawings have been omitted, and the same reference numerals have been used throughout the specification for identical or similar components.

[0052] The words and terms used in this specification and claims are not limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention in accordance with the principles by which the inventor defines terms and concepts to best describe his invention.

[0053] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings correspond to preferred embodiments of the present invention and do not represent all technical ideas of the present invention; thus, various equivalents and modifications that may replace such configurations may exist at the time of filing the present invention.

[0054] In the following description, descriptions of some components may be omitted to clarify the features of the present invention.

[0055]

[0056] In the following description, the term "connection" refers to one or more members being connected to each other in a manner that allows for fluid communication. In one embodiment, the connection may be formed by members such as a conduit, a pipe, or a piping system. In the following description, the term "connection" may be used interchangeably with the meaning that one or more members are "fluidly connected" to each other.

[0057] In the following description, the term "conduction" means that one or more components are connected to each other to transmit current or electrical signals. In one embodiment, the conduction may be formed in a wired form by a conductor member, etc., or in a wireless form such as Bluetooth, Wi-Fi, or RFID. In one embodiment, the conduction may include the meaning of "communication."

[0058] As used in the following description, the term "fluid" refers to any form of substance that flows due to an external force and whose shape or volume, etc., can be deformed. In one embodiment, the fluid may be a liquid such as water or a gas such as air.

[0059] The terms "upper side," "lower side," "left side," "right side," "front side," and "rear side" used in the following description shall be understood by referring to the coordinate system depicted throughout the attached drawings.

[0060]

[0061] Referring to FIGS. 1 to 5, an arc extinguishing mechanism (10) according to an embodiment of the present invention is illustrated. The arc extinguishing mechanism (10) may be provided in a circuit breaker, etc. The circuit breaker may be energized with an external power source and a load, respectively.

[0062] The above current may be formed as the fixed contact and the movable contact provided in the circuit breaker come into contact and conduct current. The arc extinguishing mechanism (10) may be positioned adjacent to the fixed contact or the movable contact and configured to extinguish the arc generated by the separation between them.

[0063] In particular, the arc extinguishing mechanism (10) according to an embodiment of the present invention can smoothly extend the generated arc in a direction for extinguishing it. To this end, the structure of the arc extinguishing mechanism (10) according to an embodiment of the present invention may be modified so that the second arc grid (600) and the first arc grid (700) are advantageous for arc extension.

[0064] Accordingly, the generated arc can be rapidly extended and moved without the need for additional separate components for arc extension. As a result, the arc extinguishing effect of the generated arc can be enhanced.

[0065] In the illustrated embodiment, the arc extinguishing mechanism (10) includes an arc extinguishing frame (100), an arc extinguishing side plate (200), an arc runner (300), an arc guide (400), and an arc grid (500, 600). Additionally, referring further to FIGS. 6 through 9, the arc extinguishing mechanism (10) includes other types of arc grids (700, 800).

[0066] The arc extinguishing frame (100) forms part of the outer shape of the arc extinguishing mechanism (10). The arc extinguishing frame (100) can be combined with other components of the arc extinguishing mechanism (10) to support them.

[0067] In the illustrated embodiment, the arc extinguishing frame (100) forms one side in the height direction of the arc extinguishing mechanism (10), i.e., the upper side, and is combined with and supports the arc extinguishing side plate (200).

[0068] The arc extinguishing side plate (200) is combined with other components of the arc extinguishing mechanism (10), namely the arc runner (300), arc guide (400), and arc grid (500, 600), so the arc extinguishing frame (100) can be said to indirectly support the other components of the arc extinguishing mechanism (10) through the arc extinguishing side plate (200).

[0069] The arc extinguishing frame (100) forms one side in the height direction of the arc extinguishing mechanism (10), the upper side in the illustrated embodiment. The arc extinguishing frame (100) is positioned to cover the arc extinguishing side plate (200), arc runner (300), arc guide (400), and arc grid (500, 600) from the upper side.

[0070] Although not shown, a space may be formed inside the arc extinguishing frame (100). The space may accommodate a configuration for filtering by-products remaining thereon before the generated arc is discharged to the outside.

[0071] One side in the height direction of the above space, the upper side in the illustrated embodiment, is formed open. The generated arc can be filtered by the above configuration and then discharged to the outside through the one side.

[0072] The other side in the height direction of the above space, the lower side in the illustrated embodiment, is formed open. The generated arc can be divided by a plurality of arc grids (500, 600) and guided toward the above space.

[0073] The arc extinguishing frame (100) may be of any shape that combines with and supports other components of the arc extinguishing mechanism (10) and forms a passage through which an arc passing through the arc grid (500, 600) is discharged to the outside. In the illustrated embodiment, the arc extinguishing frame (100) is a three-dimensional shape having a length in the front-rear direction that is longer than the width in the left-right direction and a height in the up-down direction.

[0074] The other side in the height direction of the arc shovel frame (100), that is, each side in the width direction of the lower side, that is, the left and right sides in the illustrated embodiment, are joined with the arc shovel side plate (200).

[0075] The arc extinguishing side plate (200) constitutes another part of the external shape of the arc extinguishing mechanism (10). The arc extinguishing side plate (200) can be combined with and supported by the arc extinguishing frame (100). At the same time, the arc extinguishing side plate (200) can be combined with and supported by other components of the arc extinguishing mechanism (10), namely the arc runner (300), arc guide (400), and arc grid (500, 600).

[0076] In the illustrated embodiment, the arc extinguishing side plate (200) constitutes each side in the width direction of the arc extinguishing mechanism (10), namely the left and right sides. The arc extinguishing side plate (200) surrounds each side in the width direction of the arc extinguishing frame (100), arc runner (300), and arc grid (500, 600) from the outside and is coupled with them. The arc extinguishing side plate (200) is coupled with each of the multiple arc guides (400) to support them.

[0077] The arc extinguishing side plate (200) is combined with the arc extinguishing frame (100) and may have any shape capable of supporting the arc runner (300), arc guide (400), and arc grid (500, 600). In the illustrated embodiment, the arc extinguishing side plate (200) is formed as a polygonal plate having a length in the front-rear direction, a thickness in the left-right direction, and a height in the up-down direction.

[0078] A plurality of through holes may be formed inside the arc extinguishing side plate (200). Some of the plurality of through holes may be coupled with protrusions formed on the arc extinguishing frame (100). Other of the plurality of through holes may be coupled with protrusions formed on the arc runner (300).

[0079] A plurality of arc extinguishing side plates (200) may be provided. A plurality of arc extinguishing side plates (200) may be connected to the arc extinguishing frame (100), arc runner (300), arc guide (400), and arc grid (500, 600) at different locations, respectively. In the illustrated embodiment, a pair of arc extinguishing side plates (200) is provided, including a first arc extinguishing side plate (210) and a second arc extinguishing side plate (220).

[0080] The first arc extinguishing side plate (210) is located on one side in the width direction of the arc extinguishing mechanism (10), on the left side in the illustrated embodiment. The first arc extinguishing side plate (210) is combined with the left portion of the arc extinguishing frame (100), arc runner (300), and arc grid (500, 600), and the first arc guide (410) to support them.

[0081] The second arc extinguishing side plate (220) is located on the other side in the width direction of the arc extinguishing mechanism (10), on the right side in the illustrated embodiment. The second arc extinguishing side plate (220) is combined with the right portion of the arc extinguishing frame (100), arc runner (300), and arc grid (500, 600), and the second arc guide (420) to support them.

[0082] The first arc extinguishing side plate (210) and the second arc extinguishing side plate (220) are arranged facing each other with an arc runner (300), an arc guide (400), and an arc grid (500, 600) placed between them.

[0083] The arc runner (300) guides the generated arc to proceed toward the arc grid (500, 600). The arc runner (300) may be positioned adjacent to the direction of movement of the movable contact (not shown). In the illustrated embodiment, the arc runner (300) is positioned on one side in the longitudinal direction of the arc extinguishing mechanism (10), in the illustrated embodiment, on the rear side.

[0084] The arc runner (300) is positioned adjacent to the arc extinguishing frame (100). The arc runner (300) can guide the generated arc toward the arc extinguishing frame (100). In the illustrated embodiment, the arc runner (300) is positioned below the arc extinguishing frame (100).

[0085] The arc runner (300) is combined with the arc extinguishing side plate (200). The arc runner (300) may be supported by the arc extinguishing side plate (200). In the illustrated embodiment, one side of the arc runner (300) in the width direction is combined and supported by the first arc extinguishing side plate (210), and the other side is combined and supported by the second arc extinguishing side plate (220). The arc runner (300) is located on one side of the arc extinguishing side plate (200) in the length direction, which is the rear side in the illustrated embodiment.

[0086] The arc runner (300) is positioned adjacent to the arc grid (500, 600). Specifically, a portion of the arc runner (300) is positioned below the arc grid body (510) and between a pair of arc grid racks (530). That is, the portion of the arc runner (300) can be positioned in a space defined by being surrounded by each portion of the arc grid (500, 600).

[0087] Accordingly, the arc generated in the above space can be rapidly guided toward the arc grid (500, 600) through the arc runner (300).

[0088] The arc runner (300) may be composed of multiple parts. One part of the arc runner (300) may extend in the height direction of the arc extinguishing mechanism (10) and may surround the arc grid (500, 600) on one side. Another part of the arc runner (300) may be continuous with the said part and may extend in the length direction of the arc extinguishing mechanism (10).

[0089] Protrusions may be formed protrudingly on each side in the width direction of the above-mentioned part and the above-mentioned other part of the arc runner (300), on the left and right sides in the illustrated embodiment, respectively. The protrusions may be inserted and coupled into through holes formed inside the first arc extinguishing side plate (210) and the second arc extinguishing side plate (220).

[0090] The arc guide (400) is configured to react with the generated arc to generate cutting gas. The arc guide (400) is coupled to the arc extinguishing side plate (200) and the arc grid (500, 600), respectively, and is positioned adjacent to a fixed contact (not shown) or a movable contact (not shown).

[0091] The arc guide (400) can react with an arc generated when a movable contact (not shown) is separated from a fixed contact (not shown). The arc guide (400) can receive cutting gas and then release the cutting gas by the heat or pressure provided by the arc.

[0092] The released cutting gas increases the pressure in the space surrounded by the arc grid (500, 600), so that the generated arc can be rapidly guided toward the arc grid (500, 600) and the arc extinguishing frame (100). Additionally, the released cutting gas can cool the arc to extinguish it.

[0093] The arc guide (400) is coupled to the arc extinguishing side plate (200). The arc guide (400) is coupled to one side in the height direction of the arc extinguishing side plate (200), and to the inner side of the lower side in the illustrated embodiment. In one embodiment, the arc guide (400) may be coupled to the arc extinguishing side plate (200) by a separate fastening member such as a screw.

[0094] The arc guide (400) is positioned adjacent to the arc runner (300). The arc guide (400) may be partially covered by the other part of the arc runner (300), namely the part extending in the front-rear direction. Thus, the arc can be rapidly induced and extinguished by the cutting gas generated in the arc guide (400) and the arc runner (300).

[0095] The arc guide (400) is coupled with the arc grid (500, 600). The arc guide (400) is coupled with an arc grid rack (530) located on one side in the height direction of the arc grid (500, 600), which is the lower side in the illustrated embodiment. At this time, the arc guide (400) may be coupled with the arc grid (500, 600) by at least partially wrapping the arc grid rack (530). In the illustrated embodiment, the arc guide (400) is coupled with the arc grid (500, 600) by surrounding a portion adjacent to the lower end of the arc grid rack (530).

[0096] The arc guide (400) is combined with the arc extinguishing side plate (200) and the arc grid (500, 600), is positioned adjacent to the arc runner (300), and may be of any shape capable of providing cutting gas in response to the generated arc. In the illustrated embodiment, the arc guide (400) is a three-dimensional shape having a triangular cross-section and a length in the front-rear direction.

[0097] The arc guide (400) may be composed of any material capable of providing cutting gas. In one embodiment, the arc guide (400) may be composed of materials such as fluoropolymer compounds, polytetrafluoroethylene (PTFE), polyamide compounds (Nylon, Polyamide, PA), polyoxymethylene (POM), ceramic, melamine resin, unsaturated polyester, and polybutylene terephthalate (PBT).

[0098] In the above embodiment, the arc guide (400) may be formed such that the cross-sectional area of ​​one side in the longitudinal direction, i.e., the front side, is greater than the cross-sectional area of ​​the other side in the longitudinal direction, i.e., the rear side.

[0099] A plurality of arc guides (400) may be provided. A plurality of arc guides (400) may each be coupled to a plurality of arc extinguishing side plates (200) and may each be coupled to an arc grid (500, 600) at different locations. In the illustrated embodiment, a pair of arc guides (400) is provided, including a first arc guide (410) and a second arc guide (420).

[0100] The first arc guide (410) is located on one side in the width direction of the arc extinguishing mechanism (10), on the left side in the illustrated embodiment. The first arc guide (410) is connected to the first arc extinguishing side plate (210) and the left arc grid rack (530), respectively.

[0101] The second arc guide (420) is located on the other side in the width direction of the arc extinguishing mechanism (10), on the right side in the illustrated embodiment. The second arc guide (420) is connected to the second arc extinguishing side plate (220) and the arc grid rack (530) on the right side, respectively.

[0102] The first arc guide (410) and the second arc guide (420) are positioned facing each other with the space formed between a pair of arc grid racks (530) in between.

[0103] The arc grid (500, 600) splits and cools the arc. The generated arc passes through the arc grid (500, 600) by the arc runner (300), splits and cools, and can be guided to the arc extinguishing frame (100). The arc grid (500, 600) substantially performs the role of cooling and extinguishing the generated arc.

[0104] The arc grid (500, 600) is combined with the arc extinguishing frame (100). One side of the arc grid (500, 600) in the height direction, the upper side in the illustrated embodiment, is partially accommodated in the arc extinguishing frame (100). The said one side of the arc grid (500, 600), i.e., the upper side, is covered by the arc extinguishing frame (100).

[0105] The arc grid (500, 600) is combined with the arc extinguishing side plate (200). Each side in the width direction of the arc grid (500, 600), the left and right sides in the illustrated embodiment, are combined with the arc extinguishing side plate (200). The arc grid (500, 600) is supported by the arc extinguishing side plate (200).

[0106] The arc grid (500, 600) is positioned adjacent to the arc runner (300). The generated arc can be guided by the arc runner (300) toward the arc grid (500, 600).

[0107] The arc grid (500, 600) is coupled with the arc guide (400). The other side in the height direction of the arc grid (500, 600), i.e., the lower side in the illustrated embodiment, is coupled with the arc guide (400). The other side of the arc grid (500, 600), i.e., the lower side, can be partially accommodated in the arc guide (400).

[0108] The arc grid (500, 600) may be formed by including any material capable of splitting and cooling the generated arc. In one embodiment, the arc grid (500, 600) may be formed of magnetizable copper (Cu), iron (Fe), or an alloy material containing these.

[0109] The arc grid (500, 600) can be combined with other components of the arc extinguishing mechanism (10) and formed in any shape capable of dividing and cooling the generated arc. In the illustrated embodiment, the arc grid (500, 600) is provided in the form of a polygonal plate having a length in the left-right direction, a height in the up-down direction, and a thickness in the front-back direction.

[0110] Multiple arc grids (500, 600) may be provided. Multiple arc grids (500, 600) may be spaced apart from each other in the longitudinal direction of the arc extinguishing frame (100) and may be combined with the arc extinguishing side plate (200) and the arc guide (400), respectively. In the illustrated embodiment, multiple arc grids (500, 600) are spaced apart in the front-rear direction.

[0111] One of the arc grids (500, 600) located on the outermost side is exposed to the outside. Another arc grid (500, 600) located on the other outermost side is surrounded by an arc runner (300).

[0112] Meanwhile, multiple arc grids (500, 600) can be divided into a first arc grid (500) and a second arc grid (600) depending on their structure and position.

[0113] That is, as best illustrated in FIGS. 6 and 7, the first arc grid (500) can be formed to have a longer length in the height direction, i.e., the vertical direction, compared to the second arc grid (600). This is because the first arc grid (500) is located relatively further forward than the second arc grid (600) and is not surrounded by the arc runner (300).

[0114] That is, the second arc grid (600) can be formed to have a shorter height compared to the first arc grid (500) to secure space for the arc runner (300) to be placed.

[0115] The first arc grid (500) and the second arc grid (600) differ in some aspects of their structure, but their connection relationship and function with other components of the arc extinguishing mechanism (10) are identical. Accordingly, the first arc grid (500) and the second arc grid (600) will be described below focusing on their structural features.

[0116] In the embodiment illustrated in FIG. 6, the first arc grid (500) includes an arc grid body (510), an arc grid head (520), an arc grid leg (530), an arc grid outer circumference (540), an arc grid inner circumference (550), and an arc grid groove (560).

[0117] The arc grid body (510) constitutes the body of the first arc grid (500). The arc grid body (510) is formed to have the largest area among the parts of the first arc grid (500). In the illustrated embodiment, the arc grid body (510) constitutes one side in the height direction of the first arc grid (500), the upper side in the illustrated embodiment.

[0118] An arc grid head (520) is formed protrudingly at one end in the height direction of the arc grid body (510), in the illustrated embodiment, at the upper end. The portion of the upper end of the arc grid body (510) where the arc grid head (520) is not formed can support the arc extinguishing frame (100).

[0119] The other end in the height direction of the arc grid body (510), the lower end in the illustrated embodiment, is continuous with the arc grid rack (530). As will be described later, a plurality of arc grid racks (530) may be provided. The lower end of the arc grid body (510) may be continuous with each of the plurality of arc grid racks (530).

[0120] An arc grid groove (560) may be formed in a recess at the other end in the height direction of the arc grid body (510), in the illustrated embodiment, at the lower end. The inner circumference surrounding the arc grid groove (560) of the part of the arc grid body (510) may be defined as an arc grid inner circumference (550).

[0121] The arc grid head (520) is formed to protrude from the upper end of the arc grid body (510). The arc grid head (520) is the part where the first arc grid (500) is joined to the arc extinguishing frame (100). The arc grid head (520) can be inserted into a space formed inside the arc extinguishing frame (100). Accordingly, the joined state of the first arc grid (500) and the arc extinguishing frame (100) can be stably maintained.

[0122] The arc grid head (520) may have a shape corresponding to the shape of the arc grid body (510). In the illustrated embodiment, the arc grid head (520) is formed as a polygonal plate having a length in the left-right direction, a height in the up-down direction, and a thickness in the front-back direction.

[0123] The arc grid head (520) is positioned to face the arc grid rack (530), arc grid outer circumference (540), arc grid inner circumference (550), and arc grid groove (560) with the arc grid body (510) in between.

[0124] The arc grid rack (530) constitutes another part of the first arc grid (500). The first arc grid (500) is formed to have a relatively small area among the parts of the arc grid rack (530). The arc grid rack (530) constitutes the other side in the height direction of the first arc grid (500), the lower side in the illustrated embodiment.

[0125] The arc grid rack (530) is the part where the first arc grid (500) is joined to the arc guide (400). The arc grid rack (530) can be joined to the arc guide (400) at least partially.

[0126] The portion of the arc grid rack (530) that is coupled with the arc guide (400) can be accommodated in a space formed inside the arc guide (400) and surrounded by the arc guide (400). In the illustrated embodiment, one side in the height direction of the arc grid rack (530), i.e., the lower side, is coupled with the arc guide (400).

[0127] The other end of the arc grid rack (530) in the height direction, the upper end in the illustrated embodiment, is continuous with the lower end of the arc grid body (510). At this time, the part where the arc grid rack (530) and the arc grid body (510) are continuous can be defined as a first projection (ow1).

[0128] The first projection (ow1) may be formed to protrude more than other parts of the inner portion of the first arc grid (500). Accordingly, an arc that tends to move toward the peak proceeds smoothly up to the first projection (ow1), but it is relatively difficult to proceed to the arc grid groove (560) located higher therefrom.

[0129] Accordingly, in order to solve the aforementioned problem, the structure of the first arc grid (700) according to another embodiment of the present invention is modified so that the first projection (nw1) is positioned higher. Accordingly, the generated arc can be extinguished by the first arc grid (700) at a higher position compared to the first arc grid (500). This will be explained later.

[0130] In the illustrated embodiment, the arc grid rack (530) is formed in the shape of a triangular plate, with its cross-sectional area increasing as it moves toward the arc grid body (510), that is, from the lower side to the upper side.

[0131] A plurality of arc grid racks (530) may be provided. A plurality of arc grid racks (530) may be spaced apart from each other and each may be connected to the arc grid body (510) at different locations. In the illustrated embodiment, a pair of arc grid racks (530) is provided, including a first arc grid rack (531) and a second arc grid rack (532).

[0132] The first arc grid rack (531) and the second arc grid rack (532) are spaced apart in the width direction, that is, the left and right direction, of the arc grid body (510). The first arc grid rack (531) is continuous with the left end of the lower side of the arc grid body (510), and the second arc grid rack (532) is continuous with the right end of the lower side of the arc grid body (510).

[0133] The height of the arc grid rack (530), the vertical length in the illustrated embodiment, can be defined as the first height (oh1). That is, the first height (oh1) can be defined as the vertical distance from the lower end of the arc grid rack (530) to the first projection (ow1).

[0134] As will be described later, the first height (nh1) of the first arc grid (700) is formed to be longer than the first height (oh1) of the first arc grid (500). Accordingly, the arc elongation length by the first arc grid (700) can be formed to be longer than the arc elongation length by the first arc grid (500).

[0135] In addition, as the first height (nh1) of the first arc grid (700) is formed to be longer than the first height (oh1) of the first arc grid (500), the area of ​​the arc grid rack (730) can be increased. Accordingly, the cooling effect of the arc can be maintained. A detailed explanation of this will be provided later.

[0136] One corner of the arc grid rack (530) can be defined as the arc grid outer edge (540).

[0137] The outer edge of the arc grid (540) forms part of the inner edge of the first arc grid (500). The outer edge of the arc grid (540) can be defined as an inner edge among the edges of the arc grid rack (530).

[0138] In other words, the arc grid perimeter (540) can be defined as each corner where the first arc grid rack (531) and the second arc grid rack (532) face each other.

[0139] The outer circumference of the arc grid (540) may extend from one end in the height direction of the arc grid rack (530), i.e., the lower end, to the other end in the height direction, i.e., the upper end. At this time, the one end of the outer circumference of the arc grid (540), the upper end in the illustrated embodiment, may be continuous with the inner circumference of the arc grid (550).

[0140] The outer edge of the arc grid (540) may have a shape corresponding to the shape of the arc grid rack (530). In the illustrated embodiment, the outer edge of the arc grid (540) extends obliquely toward the inner and upper sides in the longitudinal direction of the first arc grid (500), i.e., the left and right directions.

[0141] As described above, the arc grid rack (530) may be provided as a pair including a first arc grid rack (531) and a second arc grid rack (532). Accordingly, the arc grid outer circumference (540) may also be defined to include a first arc grid outer circumference (541) which is one corner of the first arc grid rack (531) and a second arc grid outer circumference (542) which is one corner of the second arc grid rack (532).

[0142] The first arc grid outer circumference (541) forms one side of the first arc grid rack (531), the right corner in the illustrated embodiment. The first arc grid outer circumference (541) extends obliquely upward to the right from the lower end of the first arc grid rack (531) toward the first arc grid inner circumference (551). The first arc grid outer circumference (541) is continuous with the lower end of the first arc grid inner circumference (551).

[0143] The portion where the outer circumference (541) of the first arc grid is continuous with the inner circumference (551) of the first arc grid can be defined as the first projection (ow1). As described above, the first projection (ow1) can be formed in a pointed shape protruding outward.

[0144] At this time, the upper end of the arc grid groove (560) according to the illustrated embodiment (or the third arc grid inner circumference (553) surrounding it) is positioned lower than the first center (oc1) where the extension line of the first arc grid outer circumference (541) and the extension line of the second arc grid outer circumference (542) meet.

[0145] Therefore, the lower end of the arc grid inner circumference (550) surrounding the arc grid groove (560) is also positioned relatively low, so the first projection (ow1) is positioned further down, and as a result, there is a risk that the arc, which tends to face the tip, cannot be sufficiently extended toward the arc grid body (510).

[0146] Accordingly, in another embodiment of the present invention to be described later, the first arc grid (700) is formed such that the upper end of the arc grid groove (760) (or the third arc grid inner circumference (753) surrounding it) is higher than the first center (nc1) where the extension line of the first arc grid outer circumference (741) and the extension line of the second arc grid outer circumference (742) meet.

[0147] Accordingly, since the generated arc reaches the first projection (nw1) after being extended by a longer length, the arc can be extended to a length sufficient for it to be extinguished. A detailed explanation of this will be provided later.

[0148] The second arc grid outer circumference (542) forms one side of the second arc grid rack (532), the left corner in the illustrated embodiment. The second arc grid outer circumference (542) extends obliquely to the upper left from the lower end of the second arc grid rack (532) toward the second arc grid inner circumference (552). The second arc grid outer circumference (542) is continuous with the lower end of the second arc grid inner circumference (552).

[0149] The second arc grid outer perimeter (542) is spaced apart from the first arc grid outer perimeter (541) along the length direction of the first arc grid outer perimeter (541), and in the illustrated embodiment, the left-right direction, and is positioned to face the first arc grid outer perimeter (541). A point where the extension line of the first arc grid outer perimeter (541) and the extension line of the second arc grid outer perimeter (542) meet each other can be defined as the first center (oc1).

[0150] At this time, the angle formed by the first arc grid outer circumference (541) and the second arc grid outer circumference (542) with respect to the first center (oc1) can be defined as the first angle (oa1). The first angle (oa1) may be larger than the first angle (na1) according to another embodiment to be described later.

[0151] Accordingly, the first arc grid outer circumference (541) and the second arc grid outer circumference (542) can be formed to have a gentler slope compared to the first arc grid outer circumference (741) and the second arc grid outer circumference (742) to be described later.

[0152] The upper end of the outer circumference (540) of the arc grid is continuous with the inner circumference (550) of the arc grid.

[0153] The arc grid inner circumference (550) constitutes another part of the inner circumference of the arc grid body (510). The arc grid inner circumference (550) partially surrounds the arc grid groove (560) formed by being recessed inside the arc grid body (510).

[0154] In the illustrated embodiment, the arc grid inner circumference (550) surrounds the arc grid groove (560) on the upper, left, and right sides. That is, the arc grid inner circumference (550) can be defined as a part of the inner circumference of the arc grid body (510).

[0155] One side in the height direction of the arc grid inner circumference (550), the upper side in the illustrated embodiment, surrounds the upper end of the arc grid groove (560). The upper end of the arc grid groove (560) is enclosed and closed by the arc grid inner circumference (550). Additionally, the other side in the height direction of the arc grid inner circumference (550), the lower side in the illustrated embodiment, is continuous with the upper end of the arc grid outer circumference (540).

[0156] At this time, a first projection (ow1) may be formed in the part where the inner circumference (550) of the arc grid is continuous with the outer circumference (540) of the arc grid.

[0157] The arc grid inner circumference (550) is continuous with the arc grid outer circumference (540) and can be formed in any shape that can partially surround the arc grid groove (560). In the illustrated embodiment, the arc grid inner circumference (550) is configured to include a first arc grid inner circumference (551), a second arc grid inner circumference (552), and a third arc grid inner circumference (553).

[0158] The first arc grid inner circumference (551) forms a part of the arc grid inner circumference (550). The first arc grid inner circumference (551) surrounds the arc grid groove (560) on one side in the width direction, on the left side in the illustrated embodiment. The first arc grid inner circumference (551) extends in the height direction of the arc grid groove (560), in the vertical direction in the illustrated embodiment.

[0159] One side in the height direction of the first arc grid inner circumference (551), the lower end in the illustrated embodiment, is continuous with the first arc grid outer circumference (541). The portion where the first arc grid inner circumference (551) and the first arc grid outer circumference (541) are continuous can be defined as the first projection (ow1).

[0160] The other side in the height direction of the first arc grid inner circumference (551), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (553). A first center (oc1) may be located on the extension line of the first arc grid inner circumference (551).

[0161] That is, in the embodiment illustrated in FIG. 6, the first center (oc1) is positioned on the upper side of the first arc grid inner circumference (551), so that the first center (oc1) is positioned further upper than the upper end of the first arc grid inner circumference (551).

[0162] The first arc grid inner circumference (551) is positioned to face the second arc grid inner circumference (552) with the arc grid groove (560) in between.

[0163] The second arc grid inner circumference (552) constitutes another part of the arc grid inner circumference (550). The second arc grid inner circumference (552) surrounds the arc grid groove (560) on the other side in the width direction, on the right side in the illustrated embodiment. The second arc grid inner circumference (552) extends in the height direction of the arc grid groove (560), in the vertical direction in the illustrated embodiment.

[0164] One side in the height direction of the inner circumference (552) of the second arc grid, the lower end in the illustrated embodiment, is continuous with the outer circumference (542) of the second arc grid. The inner circumference (552) of the second arc grid and the outer circumference (542) of the second arc grid may be continuous with each other at a predetermined angle. In the illustrated embodiment, the predetermined angle may be an obtuse angle.

[0165] The other side in the height direction of the second arc grid inner circumference (552), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (553). The second arc grid inner circumference (552) is continuous with one end in the extension direction of the third arc grid inner circumference (553), the right end in the illustrated embodiment.

[0166] The third arc grid inner circumference (553) constitutes the remaining part of the arc grid inner circumference (550). The third arc grid inner circumference (553) surrounds the arc grid groove (560) on one side in the height direction, in the illustrated embodiment, on the upper side. The third arc grid inner circumference (553) extends in the width direction of the arc grid groove (560), in the left-right direction in the illustrated embodiment.

[0167] At this time, the third arc grid inner circumference (553) may be rounded and extended convexly to one side in the height direction of the arc grid groove (560). In the illustrated embodiment, the third arc grid inner circumference (553) is rounded and extended convexly upward. Accordingly, it will be understood that the arc grid inner circumference (550) is formed in the shape of an inverted "U".

[0168] The third arc grid inner circumference (553) is continuous with the first arc grid inner circumference (551). One end of the third arc grid inner circumference (553) in the extension direction, the left end in the illustrated embodiment, is continuous with the upper end of the first arc grid inner circumference (551).

[0169] The third arc grid inner circumference (553) is continuous with the second arc grid inner circumference (552). The other end of the third arc grid inner circumference (553) in the extension direction, the right end in the illustrated embodiment, is continuous with the upper end of the second arc grid inner circumference (552).

[0170] Meanwhile, the vertical distance between the upper end of the third arc grid inner circumference (553) and the lower end of the second arc grid inner circumference (552) can be defined as the first depth (od1). Alternatively, the first depth (od1) can be defined as the distance between the upper end of the second arc grid outer circumference (542) and the upper end of the arc grid groove (560).

[0171] That is, it will be understood that the first depth (od1) means the vertical length, i.e., the depth, of the arc grid groove (560).

[0172] At this time, the first depth (nd1) of the first arc grid (700), which will be described later, can be formed longer than the first depth (od1) of the first arc grid (500). That is, the arc grid groove (760) of the first arc grid (700) can be formed deeper than the arc grid groove (560) of the first arc grid (500). Accordingly, the elongation length of the generated arc is increased, and the arc extinguishing effect of the arc can also be improved.

[0173] The arc grid home (560) is in communication with the space formed between the first arc grid rack (531) and the second arc grid rack (532), that is, the space where the movable contact (not shown) is located.

[0174] The arc grid home (560) provides a passage for the arc generated in the space to flow into the arc grid body (510).

[0175] The arc grid groove (560) is formed by being recessed inside the arc grid body (510). Specifically, the arc grid groove (560) is formed by being recessed on one side in the height direction of the arc grid body (510), at the lower end in the illustrated embodiment.

[0176] The arc grid groove (560) is partially enclosed by a part of the inner circumference of the arc grid body (510), namely the arc grid inner circumference (550). In the illustrated embodiment, each side in the width direction and one side in the height direction of the arc grid groove (560), namely the left, right, and upper sides, are enclosed by the arc grid inner circumference (550).

[0177] The other side in the height direction of the arc grid home (560), the lower side in the illustrated embodiment, is formed open and communicates with the space, that is, the space where the arc is generated.

[0178] The arc grid groove (560) may have a shape corresponding to the shape of the arc grid inner circumference (550). In the illustrated embodiment, the arc grid groove (560) is formed such that its vertical height is longer than its horizontal width, and its upper end is rounded so as to be convex outward.

[0179] At this time, the height of the arc grid groove (560), that is, the length in the vertical direction, can be defined as the first depth (od1). As described above, the first depth (od1) of the first arc grid (500) according to the present embodiment can be formed shorter than the first depth (nd1) of the first arc grid (700) according to another embodiment.

[0180] The first arc grid (500) is located adjacent to the second arc grid (600).

[0181] Referring to FIG. 7, a second arc grid (600) according to one embodiment of the present invention is illustrated as an example. In the illustrated embodiment, the second arc grid (600) includes an arc grid body (610), an arc grid head (620), an arc grid leg (630), an arc grid outer circumference (640), an arc grid inner circumference (650), and an arc grid groove (660).

[0182] The arc grid body (610) constitutes the body of the second arc grid (600). The arc grid body (610) is formed to have the largest area among the parts of the second arc grid (600). In the illustrated embodiment, the arc grid body (610) constitutes one side in the height direction of the second arc grid (600), the upper side in the illustrated embodiment.

[0183] An arc grid head (620) is formed protrudingly at one end in the height direction of the arc grid body (610), in the illustrated embodiment, at the upper end. The portion of the upper end of the arc grid body (610) where the arc grid head (620) is not formed can support the arc extinguishing frame (100).

[0184] The other end in the height direction of the arc grid body (610), the lower end in the illustrated embodiment, is continuous with the arc grid rack (630). As will be described later, a plurality of arc grid racks (630) may be provided. The lower end of the arc grid body (610) may be continuous with each of the plurality of arc grid racks (630).

[0185] An arc grid groove (660) may be formed in a recess at the other end in the height direction of the arc grid body (610), in the illustrated embodiment, at the lower end. The inner circumference surrounding the arc grid groove (660) of the part of the arc grid body (610) may be defined as an arc grid inner circumference (650).

[0186] The arc grid head (620) is formed to protrude from the upper end of the arc grid body (610). The arc grid head (620) is the part where the second arc grid (600) is joined to the arc extinguishing frame (100). The arc grid head (620) can be inserted into a space formed inside the arc extinguishing frame (100). Accordingly, the joined state of the second arc grid (600) and the arc extinguishing frame (100) can be stably maintained.

[0187] The arc grid head (620) may have a shape corresponding to the shape of the arc grid body (610). In the illustrated embodiment, the arc grid head (620) is formed as a polygonal plate having a length in the left-right direction, a height in the up-down direction, and a thickness in the front-back direction.

[0188] The arc grid head (620) is positioned to face the arc grid rack (630), arc grid outer circumference (640), arc grid inner circumference (650), and arc grid groove (660) with the arc grid body (610) in between.

[0189] The arc grid rack (630) constitutes another part of the second arc grid (600). The second arc grid (600) is formed to have a relatively small area among the parts of the arc grid rack (630). The arc grid rack (630) constitutes the other side in the height direction of the second arc grid (600), the lower side in the illustrated embodiment.

[0190] The arc grid rack (630) is the part where the second arc grid (600) is joined to the arc guide (400). The arc grid rack (630) can be joined to the arc guide (400) at least partially.

[0191] The portion of the arc grid rack (630) that is coupled with the arc guide (400) may be received in a space formed inside the arc guide (400) and surrounded by the arc guide (400). In the illustrated embodiment, one side in the height direction of the arc grid rack (630), i.e., the lower side, is coupled with the arc guide (400).

[0192] The other end in the height direction of the arc grid rack (630), the upper end in the illustrated embodiment, is continuous with the lower end of the arc grid body (610). At this time, the part where the arc grid rack (630) and the arc grid body (610) are continuous can be defined as a second projection (ow2).

[0193] The second projection (ow2) may be formed to protrude more than other parts of the inner portion of the second arc grid (600). Accordingly, an arc that tends to move toward the peak proceeds smoothly up to the second projection (ow2), but it is relatively difficult to proceed to the arc grid groove (660) located higher therefrom.

[0194] Accordingly, in order to solve the aforementioned problem, the structure of the second arc grid (800) according to another embodiment of the present invention is modified so that the second projection (nw2) is positioned higher. Accordingly, the generated arc can be extinguished by the second arc grid (800) at a higher position compared to the second arc grid (600). This will be explained later.

[0195] In the illustrated embodiment, the arc grid rack (630) is formed in the shape of a triangular plate, with its cross-sectional area increasing as it moves toward the arc grid body (610), that is, from the lower side to the upper side.

[0196] A plurality of arc grid racks (630) may be provided. A plurality of arc grid racks (630) may be spaced apart from each other and each may be connected to the arc grid body (610) at different locations. In the illustrated embodiment, a pair of arc grid racks (630) is provided, including a first arc grid rack (631) and a second arc grid rack (632).

[0197] The first arc grid rack (631) and the second arc grid rack (632) are spaced apart in the width direction of the arc grid body (610), that is, in the left-right direction. The first arc grid rack (631) is continuous with the left end of the lower side of the arc grid body (610), and the second arc grid rack (632) is continuous with the right end of the lower side of the arc grid body (610).

[0198] The height of the arc grid rack (630), the vertical length in the illustrated embodiment, can be defined as the second height (oh2). That is, the second height (oh2) can be defined as the vertical distance from the lower end of the arc grid rack (630) to the second projection (ow2).

[0199] As will be described later, the second height (nh2) of the second arc grid (800) is formed to be longer than the second height (oh2) of the second arc grid (600). Accordingly, the arc extension length by the second arc grid (800) can be formed to be longer than the arc extension length by the second arc grid (600).

[0200] In addition, as the second height (nh2) of the second arc grid (800) is formed to be longer than the second height (oh2) of the second arc grid (600), the area of ​​the arc grid rack (830) can be increased. Accordingly, the cooling effect of the arc can be maintained. A detailed explanation of this will be provided later.

[0201] One corner of the arc grid rack (630) can be defined as the arc grid outer edge (640).

[0202] The outer edge of the arc grid (640) forms part of the inner edge of the second arc grid (600). The outer edge of the arc grid (640) can be defined as an inner edge among the edges of the arc grid rack (630).

[0203] In other words, the arc grid perimeter (640) can be defined as each corner where the first arc grid rack (631) and the second arc grid rack (632) face each other.

[0204] The outer circumference of the arc grid (640) may extend from one end in the height direction of the arc grid rack (630), i.e., the lower end, to the other end in the height direction, i.e., the upper end. At this time, the one end of the outer circumference of the arc grid (640), the upper end in the illustrated embodiment, may be continuous with the inner circumference of the arc grid (650).

[0205] The outer edge of the arc grid (640) may have a shape corresponding to the shape of the arc grid rack (630). In the illustrated embodiment, the outer edge of the arc grid (640) extends obliquely toward the inner and upper sides in the length direction of the second arc grid (600), i.e., the left and right directions. At this time, the outer edge of the arc grid (640) may include a rounded portion that is convex toward the inner side in the width direction of the second arc grid (600), i.e., the left and right directions.

[0206] As described above, the arc grid rack (630) may be provided as a pair including a first arc grid rack (631) and a second arc grid rack (632). Accordingly, the arc grid outer edge (640) may also be defined to include a first arc grid outer edge (641) which is one corner of the first arc grid rack (631) and a second arc grid outer edge (642) which is one corner of the second arc grid rack (632).

[0207] The first arc grid outer circumference (641) forms one side of the first arc grid rack (631), the right corner in the illustrated embodiment. The first arc grid outer circumference (641) extends obliquely upward to the right from the lower end of the first arc grid rack (631) toward the first arc grid inner circumference (651). The first arc grid outer circumference (641) is continuous with the lower end of the first arc grid inner circumference (651).

[0208] The portion where the outer circumference (641) of the first arc grid is continuous with the inner circumference (651) of the first arc grid can be defined as a second projection (ow2). As described above, the second projection (ow2) can be formed in a pointed shape protruding outward.

[0209] That is, the upper end of the arc grid groove (660) according to the illustrated embodiment (or the third arc grid inner circumference (653) surrounding it) is positioned lower than the second center (oc2) where the extension line of the first arc grid outer circumference (641) and the extension line of the second arc grid outer circumference (642) meet.

[0210] Therefore, the lower end of the arc grid inner circumference (650) surrounding the arc grid groove (660) is also positioned relatively low, so the second projection (ow2) is positioned further down, and as a result, there is a risk that the arc, which tends to face the tip, will not be able to extend sufficiently toward the arc grid body (610).

[0211] Accordingly, in another embodiment of the present invention to be described later, the second arc grid (800) is formed such that the upper end of the arc grid groove (860) (or the third arc grid inner circumference (853) surrounding it) is higher than the second center (nc2) where the extension line of the first arc grid outer circumference (841) and the extension line of the second arc grid outer circumference (842) meet.

[0212] Accordingly, since the generated arc reaches the second projection (nw2) after being extended by a longer length, the arc can be extended to a length sufficient for it to be extinguished. A detailed explanation of this will be provided later.

[0213] The second arc grid outer circumference (642) forms one side of the second arc grid rack (632), the left corner in the illustrated embodiment. The second arc grid outer circumference (642) extends obliquely to the upper left from the lower end of the second arc grid rack (632) toward the second arc grid inner circumference (652). The second arc grid outer circumference (642) is continuous with the lower end of the second arc grid inner circumference (652).

[0214] The second arc grid outer circumference (642) is spaced apart from the first arc grid outer circumference (641) along the length direction of the first arc grid outer circumference (641), and in the illustrated embodiment, the left-right direction, and is positioned to face the first arc grid outer circumference (641). A point where the extension line of the first arc grid outer circumference (641) and the extension line of the second arc grid outer circumference (642) meet each other can be defined as the second center (oc2).

[0215] At this time, the angle formed by the outer circumference of the first arc grid (641) and the outer circumference of the second arc grid (642) with respect to the second center (oc2) can be defined as the second angle (oa2). The second angle (oa2) may be larger than the second angle (na2) according to another embodiment to be described later.

[0216] Accordingly, the first arc grid outer circumference (641) and the second arc grid outer circumference (642) can be formed to have a gentler slope compared to the first arc grid outer circumference (841) and the second arc grid outer circumference (842) to be described later.

[0217] The upper end of the outer circumference (640) of the arc grid is continuous with the inner circumference (650) of the arc grid.

[0218] The arc grid inner circumference (650) constitutes another part of the inner circumference of the arc grid body (610). The arc grid inner circumference (650) partially surrounds the arc grid groove (660) formed by being recessed inside the arc grid body (610).

[0219] In the illustrated embodiment, the arc grid inner circumference (650) surrounds the arc grid groove (660) on the upper, left, and right sides. That is, the arc grid inner circumference (650) can be defined as a part of the inner circumference of the arc grid body (610).

[0220] One side in the height direction of the arc grid inner circumference (650), the upper side in the illustrated embodiment, surrounds the upper end of the arc grid groove (660). The upper end of the arc grid groove (660) is enclosed and closed by the arc grid inner circumference (650). Additionally, the other side in the height direction of the arc grid inner circumference (650), the lower side in the illustrated embodiment, is continuous with the upper end of the arc grid outer circumference (640).

[0221] At this time, a second projection (ow2) may be formed in the part where the inner circumference (650) of the arc grid is continuous with the outer circumference (640) of the arc grid.

[0222] The arc grid inner circumference (650) may be formed in any shape that is continuous with the arc grid outer circumference (640) and partially surrounds the arc grid groove (660). In the illustrated embodiment, the arc grid inner circumference (650) is configured to include a first arc grid inner circumference (651), a second arc grid inner circumference (652), and a third arc grid inner circumference (653).

[0223] The first arc grid inner circumference (651) forms a part of the arc grid inner circumference (650). The first arc grid inner circumference (651) surrounds the arc grid groove (660) on one side in the width direction, on the left side in the illustrated embodiment. The first arc grid inner circumference (651) extends in the height direction of the arc grid groove (660), in the vertical direction in the illustrated embodiment.

[0224] One side in the height direction of the first arc grid inner circumference (651), the lower end in the illustrated embodiment, is continuous with the first arc grid outer circumference (641). The portion where the first arc grid inner circumference (651) and the first arc grid outer circumference (641) are continuous can be defined as a second projection (ow2).

[0225] The other side in the height direction of the first arc grid inner circumference (651), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (653). A second center (oc2) may be located on the extension line of the first arc grid inner circumference (651).

[0226] That is, in the embodiment illustrated in FIG. 7, a second center (oc2) is positioned above the first arc grid inner circumference (651), so that the second center (oc2) is positioned further above the upper end of the first arc grid inner circumference (651).

[0227] The first arc grid inner circumference (651) is positioned to face the second arc grid inner circumference (652) with the arc grid groove (660) in between.

[0228] The second arc grid inner circumference (652) constitutes another part of the arc grid inner circumference (650). The second arc grid inner circumference (652) surrounds the arc grid groove (660) on the other side in the width direction, on the right side in the illustrated embodiment. The second arc grid inner circumference (652) extends in the height direction of the arc grid groove (660), in the vertical direction in the illustrated embodiment.

[0229] One side in the height direction of the inner circumference (652) of the second arc grid, the lower end in the illustrated embodiment, is continuous with the outer circumference (642) of the second arc grid. The inner circumference (652) of the second arc grid and the outer circumference (642) of the second arc grid may be continuous with each other at a predetermined angle. In the illustrated embodiment, the predetermined angle may be an obtuse angle.

[0230] The other side in the height direction of the second arc grid inner circumference (652), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (653). The second arc grid inner circumference (652) is continuous with one end in the extension direction of the third arc grid inner circumference (653), the right end in the illustrated embodiment.

[0231] The third arc grid inner circumference (653) constitutes the remainder of the arc grid inner circumference (650). The third arc grid inner circumference (653) surrounds the arc grid groove (660) on one side in the height direction, in the illustrated embodiment, on the upper side. The third arc grid inner circumference (653) extends in the width direction of the arc grid groove (660), in the left-right direction in the illustrated embodiment.

[0232] At this time, the third arc grid inner circumference (653) may be rounded and extended convexly to one side in the height direction of the arc grid groove (660). In the illustrated embodiment, the third arc grid inner circumference (653) is rounded and extended convexly upward. Accordingly, it will be understood that the arc grid inner circumference (650) is formed in the shape of an inverted "U".

[0233] The third arc grid inner circumference (653) is continuous with the first arc grid inner circumference (651). One end of the third arc grid inner circumference (653) in the extension direction, the left end in the illustrated embodiment, is continuous with the upper end of the first arc grid inner circumference (651).

[0234] The third arc grid inner circumference (653) is continuous with the second arc grid inner circumference (652). The other end of the third arc grid inner circumference (653) in the extension direction, the right end in the illustrated embodiment, is continuous with the upper end of the second arc grid inner circumference (652).

[0235] Meanwhile, the vertical distance between the upper end of the third arc grid inner circumference (653) and the lower end of the second arc grid inner circumference (652) can be defined as the second depth (od2). Alternatively, the second depth (od2) can be defined as the distance between the upper end of the second arc grid outer circumference (642) and the upper end of the arc grid groove (660).

[0236] That is, it will be understood that the second depth (od2) means the vertical length, i.e., the depth, of the arc grid groove (660).

[0237] At this time, the second depth (nd2) of the second arc grid (800), which will be described later, can be formed to be longer than the second depth (od2) of the second arc grid (600). That is, the arc grid groove (860) of the second arc grid (800) can be formed deeper than the arc grid groove (660) of the second arc grid (600). Accordingly, the elongation length of the generated arc is increased, and the arc extinguishing effect of the arc can also be improved.

[0238] The arc grid home (660) is in communication with the space formed between the first arc grid rack (631) and the second arc grid rack (632), that is, the space where the movable contact (not shown) is located.

[0239] The arc grid home (660) provides a passage for the arc generated in the space to flow into the arc grid body (610).

[0240] The arc grid groove (660) is formed by being recessed inside the arc grid body (610). Specifically, the arc grid groove (660) is formed by being recessed on one side in the height direction of the arc grid body (610), at the lower end in the illustrated embodiment.

[0241] The arc grid groove (660) is partially enclosed by a part of the inner circumference of the arc grid body (610), namely the arc grid inner circumference (650). In the illustrated embodiment, each side in the width direction and one side in the height direction of the arc grid groove (660), namely the left, right, and upper sides, are enclosed by the arc grid inner circumference (650).

[0242] The other side in the height direction of the arc grid home (660), the lower side in the illustrated embodiment, is formed open and communicates with the space, that is, the space where the arc is generated.

[0243] The arc grid groove (660) may have a shape corresponding to the shape of the arc grid inner circumference (650). In the illustrated embodiment, the arc grid groove (660) is formed such that its vertical height is longer than its horizontal width, and its upper end is rounded so that it is convex outward.

[0244] At this time, the height of the arc grid groove (660), that is, the length in the vertical direction, can be defined as the second depth (od2). As described above, the second depth (od2) of the second arc grid (600) according to the present embodiment can be formed shorter than the second depth (nd2) of the second arc grid (800) according to another embodiment.

[0245]

[0246] Referring to FIGS. 8 and 9, a first arc grid (700) and a second arc grid (800) according to another embodiment of the present invention are illustrated as examples. The first arc grid (700) and the second arc grid (800) according to the illustrated embodiment have some differences in structure compared to the first arc grid (500) and the second arc grid (600) according to the above-described embodiment.

[0247] Specifically, the first arc grid (700) is formed such that the height of the arc grid body (710), i.e., the first height (nh1), is longer than the first height (oh1) of the first arc grid (500) according to the embodiment described above.

[0248] Additionally, the first projection (nw1) is positioned higher than the first projection (ow1) of the first arc grid (500), and the first depth (nd1) of the arc grid groove (760) is formed deeper than the first depth (od1) of the first arc grid (500).

[0249] Likewise, the second arc grid (800) is formed such that the height of the arc grid body (810), i.e., the second height (nh2), is longer than the second height (oh2) of the second arc grid (600) according to the embodiment described above.

[0250] Additionally, the second projection (nw2) is positioned higher than the second projection (ow2) of the second arc grid (600), and the second depth (nd2) of the arc grid groove (760) is formed deeper than the second depth (od2) of the second arc grid (600).

[0251] Accordingly, as described above, the arc extinguishing effect of the first arc grid (700) can be further enhanced compared to the arc extinguishing effect of the first arc grid (500). Additionally, the arc extinguishing effect of the second arc grid (800) can also be further enhanced compared to the arc extinguishing effect of the second arc grid (600).

[0252] At the same time, the area of ​​the first arc grid (700) and the second arc grid (800) can be maintained to be the same as the area of ​​the first arc grid (500) and the second arc grid (600). Thus, the arc extinguishing effect can be enhanced, while the arc cooling effect can also be maintained.

[0253] Referring to FIG. 8, the first arc grid (700) includes an arc grid body (710), an arc grid head (720), an arc grid leg (730), an arc grid outer circumference (740), an arc grid inner circumference (750), and an arc grid groove (760).

[0254] The arc grid body (710) constitutes the body of the first arc grid (700). The arc grid body (710) is formed to have the largest area among the parts of the first arc grid (700). In the illustrated embodiment, the arc grid body (710) constitutes one side in the height direction of the first arc grid (700), the upper side in the illustrated embodiment.

[0255] An arc grid head (720) is formed protrudingly at one end in the height direction of the arc grid body (710), in the illustrated embodiment, at the upper end. The portion of the upper end of the arc grid body (710) where the arc grid head (720) is not formed can support the arc extinguishing frame (100).

[0256] The other end in the height direction of the arc grid body (710), the lower end in the illustrated embodiment, is continuous with the arc grid rack (730). As will be described later, a plurality of arc grid racks (730) may be provided. The lower end of the arc grid body (710) may be continuous with each of the plurality of arc grid racks (730).

[0257] An arc grid groove (760) may be formed in a recess at the other end in the height direction of the arc grid body (710), in the illustrated embodiment, at the lower end. The inner circumference surrounding the arc grid groove (760) of the part of the arc grid body (710) may be defined as an arc grid inner circumference (750).

[0258] Meanwhile, as will be described later, the arc grid groove (760) may be formed to have a first depth (nd1) that is deeper than the first depth (od1) of the arc grid groove (560) of the first arc grid (500) according to the above-described embodiment. That is, considering only the change in the shape of the arc grid groove (760), the area of ​​the arc grid body (710) may be reduced compared to the arc grid body (510) according to the above-described embodiment.

[0259] In this case, the cooling effect of the arc by the first arc grid (700) can be reduced by the amount of the reduction in the area of ​​the arc grid body (710).

[0260] Accordingly, the first arc grid (700) according to the present embodiment can be configured such that the length of the arc grid rack (730) portion, that is, the size of the first height (nh1), is increased. That is, the reduction in area caused by the arc grid groove (760) can be offset by the increase in area of ​​the arc grid rack (730).

[0261] Accordingly, the area of ​​the first arc grid (700) can be maintained at the same level. As a result, the arc extinguishing effect of the arc generated when interrupting a small current can be improved, while the cooling effect of the arc can also be maintained.

[0262] The arc grid head (720) is formed to protrude from the upper end of the arc grid body (710). The arc grid head (720) is the part where the first arc grid (700) is joined to the arc extinguishing frame (100). The arc grid head (720) can be inserted into a space formed inside the arc extinguishing frame (100). Accordingly, the joined state of the first arc grid (700) and the arc extinguishing frame (100) can be stably maintained.

[0263] The arc grid head (720) may have a shape corresponding to the shape of the arc grid body (710). In the illustrated embodiment, the arc grid head (720) is formed as a polygonal plate having a length in the left-right direction, a height in the up-down direction, and a thickness in the front-back direction.

[0264] The arc grid head (720) is positioned to face the arc grid rack (730), arc grid outer circumference (740), arc grid inner circumference (750), and arc grid groove (760) with the arc grid body (710) in between.

[0265] The arc grid rack (730) constitutes another part of the first arc grid (700). The first arc grid (700) is formed to have a relatively small area among the parts of the arc grid rack (730). The arc grid rack (730) constitutes the other side in the height direction of the first arc grid (700), the lower side in the illustrated embodiment.

[0266] The arc grid rack (730) is the part where the first arc grid (700) is joined to the arc guide (400). The arc grid rack (730) can be joined to the arc guide (400) at least partially.

[0267] The portion of the arc grid rack (730) that is coupled with the arc guide (400) can be accommodated in a space formed inside the arc guide (400) and surrounded by the arc guide (400). In the illustrated embodiment, one side in the height direction of the arc grid rack (730), i.e., the lower side, is coupled with the arc guide (400).

[0268] The other end in the height direction of the arc grid rack (730), the upper end in the illustrated embodiment, is continuous with the lower end of the arc grid body (710). At this time, the part where the arc grid rack (730) and the arc grid body (710) are continuous can be defined as a first projection (nw1).

[0269] As described above, the structure of the first arc grid (700) according to the present embodiment is modified so that the first protrusion (nw1) is positioned higher in order to solve the problem described above, namely, the problem that sufficient pressure for arc expansion is not generated when a small current is passed.

[0270] To this end, the first height (nh1) of the first arc grid (700) according to the present embodiment is formed to be longer than the first height (oh1) of the first arc grid (500). Due to this structural change, the first protrusion (nw1) is also positioned above the first protrusion (ow1) according to the above embodiment.

[0271] Accordingly, the arc extension length by the first arc grid (700) can be formed to be longer than the arc extension length by the first arc grid (500).

[0272] Additionally, as the first height (nh1) increases, the generated arc can be extended and separated (i.e., extinguished) in a higher portion of the first arc grid (700). That is, the generated arc can be easily extended to a higher portion of the first arc grid (700), thereby improving the arc extinguishing effect.

[0273] In particular, even in the case of a small current circuit breaker where it is difficult to generate sufficient pressure for arc extinguishing, the generated arc can extend to the upper part of the first arc grid (700). Accordingly, the arc extinguishing effect of the generated arc can be improved even in the case of a circuit breaker through which a small current is conducted.

[0274] Furthermore, as the first height (nh1) of the arc grid rack (730) increases, the area of ​​the arc grid rack (730) itself can be increased. Accordingly, as described above, the decrease in the area of ​​the arc grid body (710) due to the increase in the depth of the arc grid groove (760) is offset, and the area of ​​the arc grid body (710) can be maintained.

[0275] In the illustrated embodiment, the arc grid rack (730) is formed in the shape of a triangular plate, with its cross-sectional area increasing as it moves toward the arc grid body (710), that is, from the lower side to the upper side.

[0276] A plurality of arc grid racks (730) may be provided. A plurality of arc grid racks (730) may be spaced apart from each other and each may be connected to the arc grid body (710) at different locations. In the illustrated embodiment, a pair of arc grid racks (730) is provided, including a first arc grid rack (731) and a second arc grid rack (732).

[0277] The first arc grid rack (731) and the second arc grid rack (732) are spaced apart in the width direction of the arc grid body (710), that is, in the left-right direction. The first arc grid rack (731) is continuous with the left end of the lower side of the arc grid body (710), and the second arc grid rack (732) is continuous with the right end of the lower side of the arc grid body (710).

[0278] The height of the arc grid rack (730), the vertical length in the illustrated embodiment, can be defined as the first height (nh1). That is, the first height (nh1) can be defined as the vertical distance from the lower end of the arc grid rack (730) to the first projection (nw1).

[0279] One corner of the arc grid rack (730) can be defined as the arc grid outer edge (740).

[0280] The outer edge of the arc grid (740) forms part of the inner edge of the first arc grid (700). The outer edge of the arc grid (740) can be defined as an inner edge among the edges of the arc grid rack (730).

[0281] In other words, the arc grid perimeter (740) can be defined as each corner where the first arc grid rack (731) and the second arc grid rack (732) face each other.

[0282] The outer circumference of the arc grid (740) may extend from one end in the height direction of the arc grid rack (730), i.e., the lower end, to the other end in the height direction, i.e., the upper end. At this time, the one end of the outer circumference of the arc grid (740), the upper end in the illustrated embodiment, may be continuous with the inner circumference of the arc grid (750).

[0283] The outer edge of the arc grid (740) may have a shape corresponding to the shape of the arc grid rack (730). In the illustrated embodiment, the outer edge of the arc grid (740) extends obliquely toward the inner and upper sides in the longitudinal direction of the first arc grid (700), i.e., the left and right directions.

[0284] As described above, the arc grid rack (730) may be provided as a pair including a first arc grid rack (731) and a second arc grid rack (732). Accordingly, the arc grid outer circumference (740) may also be defined to include a first arc grid outer circumference (741) which is one corner of the first arc grid rack (731) and a second arc grid outer circumference (742) which is one corner of the second arc grid rack (732).

[0285] The first arc grid outer circumference (741) forms one side of the first arc grid rack (731), the right corner in the illustrated embodiment. The first arc grid outer circumference (741) extends obliquely upward to the right from the lower end of the first arc grid rack (731) toward the first arc grid inner circumference (751). The first arc grid outer circumference (741) is continuous with the lower end of the first arc grid inner circumference (751).

[0286] The portion where the outer circumference (741) of the first arc grid is continuous with the inner circumference (751) of the first arc grid can be defined as the first projection (nw1). As described above, the first projection (nw1) can be formed in a pointed shape protruding outward.

[0287] That is, the upper end of the arc grid groove (760) according to the illustrated embodiment (or the third arc grid inner circumference (753) surrounding it) is positioned higher than the first center (nc1) where the extension line of the first arc grid outer circumference (741) and the extension line of the second arc grid outer circumference (742) meet.

[0288] Accordingly, the lower end of the arc grid inner circumference (750) surrounding the arc grid groove (760) is also positioned relatively high, so that the first projection (nw1) is positioned further upward. As a result, the generated arc reaches the first projection (nw1) after being extended by a longer length, so the arc can be extended to a length sufficient for extinguishing, thereby improving the arc extinguishing effect.

[0289] The second arc grid outer circumference (742) forms one side of the second arc grid rack (732), the left corner in the illustrated embodiment. The second arc grid outer circumference (742) extends obliquely to the upper left from the lower end of the second arc grid rack (732) toward the second arc grid inner circumference (752). The second arc grid outer circumference (742) is continuous with the lower end of the second arc grid inner circumference (752).

[0290] The second arc grid outer perimeter (742) is spaced apart from the first arc grid outer perimeter (741) along the length direction of the first arc grid outer perimeter (741), and in the illustrated embodiment, the left-right direction, and is positioned to face the first arc grid outer perimeter (741). A point where the extension line of the first arc grid outer perimeter (741) and the extension line of the second arc grid outer perimeter (742) meet each other can be defined as the first center (nc1).

[0291] At this time, the angle formed by the first arc grid outer circumference (741) and the second arc grid outer circumference (742) with respect to the first center (nc1) can be defined as the first angle (na1). The first angle (na1) is formed to be smaller than the first angle (oa1) according to the above-described embodiment.

[0292] Accordingly, the first arc grid outer circumference (741) and the second arc grid outer circumference (742) can be formed to have a steeper slope compared to the first arc grid outer circumference (541) and the second arc grid outer circumference (542) described above.

[0293] The upper end of the outer circumference (740) of the arc grid is continuous with the inner circumference (750) of the arc grid.

[0294] The arc grid inner circumference (750) constitutes another part of the inner circumference of the arc grid body (710). The arc grid inner circumference (750) partially surrounds the arc grid groove (760) formed by being recessed inside the arc grid body (710).

[0295] In the illustrated embodiment, the arc grid inner circumference (750) surrounds the arc grid groove (760) on the upper, left, and right sides. That is, the arc grid inner circumference (750) can be defined as a part of the inner circumference of the arc grid body (710).

[0296] One side in the height direction of the arc grid inner circumference (750), the upper side in the illustrated embodiment, surrounds the upper end of the arc grid groove (760). The upper end of the arc grid groove (760) is enclosed and closed by the arc grid inner circumference (750). Additionally, the other side in the height direction of the arc grid inner circumference (750), the lower side in the illustrated embodiment, is continuous with the upper end of the arc grid outer circumference (740).

[0297] At this time, a first projection (nw1) may be formed in the part where the inner circumference (750) of the arc grid is continuous with the outer circumference (740) of the arc grid.

[0298] The arc grid inner circumference (750) may be formed in any shape that is continuous with the arc grid outer circumference (740) and partially surrounds the arc grid groove (760). In the illustrated embodiment, the arc grid inner circumference (750) is configured to include a first arc grid inner circumference (751), a second arc grid inner circumference (752), and a third arc grid inner circumference (753).

[0299] The first arc grid inner circumference (751) forms a part of the arc grid inner circumference (750). The first arc grid inner circumference (751) surrounds the arc grid groove (760) on one side in the width direction, on the left side in the illustrated embodiment. The first arc grid inner circumference (751) extends in the height direction of the arc grid groove (760), in the vertical direction in the illustrated embodiment.

[0300] One side in the height direction of the first arc grid inner circumference (751), the lower end in the illustrated embodiment, is continuous with the first arc grid outer circumference (741). The portion where the first arc grid inner circumference (751) and the first arc grid outer circumference (741) are continuous can be defined as the first projection (nw1).

[0301] The other side in the height direction of the first arc grid inner circumference (751), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (753). A first center (nc1) may be located on the first arc grid inner circumference (751).

[0302] That is, in the embodiment illustrated in FIG. 8, a first center (nc1) is positioned on the first arc grid inner circumference (751), and the first center (nc1) is positioned further down than the upper end of the first arc grid inner circumference (751).

[0303] The first arc grid inner circumference (751) is positioned to face the second arc grid inner circumference (752) with the arc grid groove (760) in between.

[0304] The second arc grid inner circumference (752) constitutes another part of the arc grid inner circumference (750). The second arc grid inner circumference (752) surrounds the arc grid groove (760) on the other side in the width direction, on the right side in the illustrated embodiment. The second arc grid inner circumference (752) extends in the height direction of the arc grid groove (760), in the vertical direction in the illustrated embodiment.

[0305] One side in the height direction of the inner circumference (752) of the second arc grid, the lower end in the illustrated embodiment, is continuous with the outer circumference (742) of the second arc grid. The inner circumference (752) of the second arc grid and the outer circumference (742) of the second arc grid may be continuous with each other at a predetermined angle. In the illustrated embodiment, the predetermined angle may be an obtuse angle.

[0306] The other side in the height direction of the second arc grid inner circumference (752), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (753). The second arc grid inner circumference (752) is continuous with one end in the extension direction of the third arc grid inner circumference (753), the right end in the illustrated embodiment.

[0307] The third arc grid inner circumference (753) constitutes the remainder of the arc grid inner circumference (750). The third arc grid inner circumference (753) surrounds the arc grid groove (760) on one side in the height direction, in the illustrated embodiment, on the upper side. The third arc grid inner circumference (753) extends in the width direction of the arc grid groove (760), in the left-right direction, in the illustrated embodiment.

[0308] At this time, the third arc grid inner circumference (753) may be rounded and extended convexly to one side in the height direction of the arc grid groove (760). In the illustrated embodiment, the third arc grid inner circumference (753) is rounded and extended convexly upward. Accordingly, it will be understood that the arc grid inner circumference (750) is formed in the shape of an inverted "U".

[0309] The third arc grid inner circumference (753) is continuous with the first arc grid inner circumference (751). One end of the third arc grid inner circumference (753) in the extension direction, the left end in the illustrated embodiment, is continuous with the upper end of the first arc grid inner circumference (751).

[0310] The third arc grid inner circumference (753) is continuous with the second arc grid inner circumference (752). The other end of the third arc grid inner circumference (753) in the extension direction, the right end in the illustrated embodiment, is continuous with the upper end of the second arc grid inner circumference (752).

[0311] Meanwhile, the vertical distance between the upper end of the third arc grid inner circumference (753) and the lower end of the second arc grid inner circumference (752) can be defined as the first depth (nd1). Alternatively, the first depth (nd1) can be defined as the distance between the upper end of the second arc grid outer circumference (742) and the upper end of the arc grid groove (760).

[0312] That is, it will be understood that the first depth (nd1) means the vertical length, i.e., the depth, of the arc grid groove (760).

[0313] At this time, the first depth (nd1) of the first arc grid (700) can be formed longer than the first depth (od1) of the first arc grid (500) described above. That is, the arc grid groove (760) of the first arc grid (700) can be formed deeper than the arc grid groove (560) of the first arc grid (500). Accordingly, the elongation length of the generated arc is increased, and the arc extinguishing effect of the arc can also be improved.

[0314] The arc grid home (760) is in communication with the space formed between the first arc grid rack (731) and the second arc grid rack (732), that is, the space where the movable contact (not shown) is located.

[0315] The arc grid home (760) provides a passage for the arc generated in the space to flow into the arc grid body (710).

[0316] The arc grid groove (760) is formed by being recessed inside the arc grid body (710). Specifically, the arc grid groove (760) is formed by being recessed on one side in the height direction of the arc grid body (710), at the lower end in the illustrated embodiment.

[0317] The arc grid groove (760) is partially enclosed by a part of the inner circumference of the arc grid body (710), namely the arc grid inner circumference (750). In the illustrated embodiment, each side in the width direction and one side in the height direction of the arc grid groove (760), namely the left, right, and upper sides, are enclosed by the arc grid inner circumference (750).

[0318] The other side in the height direction of the arc grid home (760), the lower side in the illustrated embodiment, is formed open and communicates with the space, that is, the space where the arc is generated.

[0319] The arc grid groove (760) may have a shape corresponding to the shape of the arc grid inner circumference (750). In the illustrated embodiment, the arc grid groove (760) is formed such that its vertical height is longer than its horizontal width, and its upper end is rounded so as to be convex outward.

[0320] At this time, the height of the arc grid groove (760), that is, the length in the vertical direction, can be defined as the first depth (nd1). As described above, the first depth (nd1) of the first arc grid (700) according to the present embodiment can be formed deeper than the first depth (od1) of the first arc grid (500) according to another embodiment.

[0321] Meanwhile, although not illustrated, the arc grid groove (760) may be formed to have a longer length and a narrower width. In the above embodiment, the upper end of the arc grid groove (760) is located higher than the first center (nc1).

[0322] In addition, in the above embodiment, the first angle (na1), which is the angle formed by the first arc grid rack (731) and the second arc grid rack (732), may be the same as the first angle (oa1) according to the above embodiment.

[0323] The first arc grid (700) is located adjacent to the second arc grid (800).

[0324] Referring to FIG. 9, a second arc grid (800) according to one embodiment of the present invention is illustrated as an example. In the illustrated embodiment, the second arc grid (800) includes an arc grid body (810), an arc grid head (820), an arc grid leg (830), an arc grid outer circumference (840), an arc grid inner circumference (850), and an arc grid groove (860).

[0325] The arc grid body (810) constitutes the body of the second arc grid (800). The arc grid body (810) is formed to have the largest area among the parts of the second arc grid (800). In the illustrated embodiment, the arc grid body (810) constitutes one side in the height direction of the second arc grid (800), the upper side in the illustrated embodiment.

[0326] An arc grid head (820) is formed protrudingly at one end in the height direction of the arc grid body (810), in the illustrated embodiment, at the upper end. The portion of the upper end of the arc grid body (810) where the arc grid head (820) is not formed can support the arc extinguishing frame (100).

[0327] The other end in the height direction of the arc grid body (810), the lower end in the illustrated embodiment, is continuous with the arc grid rack (830). As will be described later, a plurality of arc grid racks (830) may be provided. The lower end of the arc grid body (810) may be continuous with each of the plurality of arc grid racks (830).

[0328] An arc grid groove (860) may be formed in a recess at the other end in the height direction of the arc grid body (810), in the illustrated embodiment, at the lower end. The inner circumference surrounding the arc grid groove (860) of the part of the arc grid body (810) may be defined as an arc grid inner circumference (850).

[0329] Meanwhile, as will be described later, the arc grid groove (860) may be formed to have a second depth (nd2) that is deeper than the second depth (od2) of the arc grid groove (560) of the second arc grid (500) according to the above-described embodiment. That is, considering only the change in the shape of the arc grid groove (860), the area of ​​the arc grid body (810) may be reduced compared to the arc grid body (510) according to the above-described embodiment.

[0330] In this case, the cooling effect of the arc by the second arc grid (800) can be reduced by the amount of the reduction in the area of ​​the arc grid body (810).

[0331] Accordingly, the second arc grid (800) according to the present embodiment can be configured such that the length of the arc grid rack (830) portion, that is, the size of the second height (nh2), is increased. That is, the reduction in area caused by the arc grid groove (860) can be offset by the increase in area of ​​the arc grid rack (830).

[0332] Accordingly, the area of ​​the second arc grid (800) can be maintained at the same level. As a result, the arc extinguishing effect of the arc generated when the small current is interrupted can be improved, while the arc cooling effect can also be maintained.

[0333] The arc grid head (820) is formed to protrude from the upper end of the arc grid body (810). The arc grid head (820) is the part where the second arc grid (800) is joined to the arc extinguishing frame (100). The arc grid head (820) can be inserted into a space formed inside the arc extinguishing frame (100). Accordingly, the joined state of the second arc grid (800) and the arc extinguishing frame (100) can be stably maintained.

[0334] The arc grid head (820) may have a shape corresponding to the shape of the arc grid body (810). In the illustrated embodiment, the arc grid head (820) is formed as a polygonal plate having a length in the left-right direction, a height in the up-down direction, and a thickness in the front-back direction.

[0335] The arc grid head (820) is positioned to face the arc grid rack (830), arc grid outer circumference (840), arc grid inner circumference (850), and arc grid groove (860) with the arc grid body (810) in between.

[0336] The arc grid rack (830) constitutes another part of the second arc grid (800). The second arc grid (800) is formed to have a relatively small area among the parts of the arc grid rack (830). The arc grid rack (830) constitutes the other side in the height direction of the second arc grid (800), the lower side in the illustrated embodiment.

[0337] The arc grid rack (830) is the part where the second arc grid (800) is joined to the arc guide (400). The arc grid rack (830) can be joined to the arc guide (400) at least partially.

[0338] The portion of the arc grid rack (830) that is coupled with the arc guide (400) may be accommodated in a space formed inside the arc guide (400) and surrounded by the arc guide (400). In the illustrated embodiment, one side in the height direction of the arc grid rack (830), i.e., the lower side, is coupled with the arc guide (400).

[0339] The other end in the height direction of the arc grid rack (830), the upper end in the illustrated embodiment, is continuous with the lower end of the arc grid body (810). At this time, the part where the arc grid rack (830) and the arc grid body (810) are continuous can be defined as a second projection (nw2).

[0340] The second projection (nw2) may be formed to protrude more than other parts of the inner portion of the second arc grid (800). Accordingly, an arc that tends to move toward the peak proceeds smoothly up to the second projection (nw2), but it is relatively difficult to proceed to the arc grid groove (860) located higher therefrom.

[0341] Accordingly, as described above, the structure of the second arc grid (800) according to the present embodiment is modified so that the second protrusion (nw2) is positioned higher in order to solve the problem described above, namely, the problem that sufficient pressure for arc expansion is not generated when a small current is passed.

[0342] To this end, the second height (nh2) of the second arc grid (800) according to the present embodiment is formed to be longer than the second height (oh2) of the second arc grid (600). Due to this structural change, the second projection (nw2) is also positioned above the second projection (ow2) according to the above embodiment.

[0343] In the illustrated embodiment, the arc grid rack (830) is formed in the shape of a triangular plate, with its cross-sectional area increasing as it moves toward the arc grid body (810), that is, from the lower side to the upper side.

[0344] A plurality of arc grid racks (830) may be provided. A plurality of arc grid racks (830) may be spaced apart from each other and each may be connected to the arc grid body (810) at different locations. In the illustrated embodiment, a pair of arc grid racks (830) is provided, including a first arc grid rack (831) and a second arc grid rack (832).

[0345] The first arc grid rack (831) and the second arc grid rack (832) are spaced apart in the width direction of the arc grid body (810), that is, in the left-right direction. The first arc grid rack (831) is continuous with the left end of the lower side of the arc grid body (810), and the second arc grid rack (832) is continuous with the right end of the lower side of the arc grid body (810).

[0346] The height of the arc grid rack (830), the vertical length in the illustrated embodiment, can be defined as the second height (nh2). That is, the second height (nh2) can be defined as the vertical distance from the lower end of the arc grid rack (830) to the second projection (nw2).

[0347] At this time, the second height (nh2) of the arc grid rack (830) is formed to be longer than the second height (oh2) of the arc grid rack (630) described above.

[0348] Accordingly, the arc extension length by the second arc grid (800) can be formed to be longer than the arc extension length by the second arc grid (600).

[0349] Additionally, as the second height (nh2) increases, the generated arc can be extended and separated (i.e., extinguished) in a higher portion of the second arc grid (800). That is, the generated arc can be easily extended to a higher portion of the second arc grid (800), thereby improving the arc extinguishing effect.

[0350] In particular, even in the case of a small current circuit breaker where it is difficult to generate sufficient pressure for arc extinguishing, the generated arc can extend to the upper part of the second arc grid (800). Accordingly, the arc extinguishing effect of the generated arc can be improved even in the case of a circuit breaker through which a small current is conducted.

[0351] Furthermore, as the second height (nh2) of the arc grid rack (830) increases, the area of ​​the arc grid rack (830) itself can be increased. Accordingly, as described above, the decrease in the area of ​​the arc grid body (810) due to the increase in the depth of the arc grid groove (860) is offset, and the area of ​​the arc grid body (810) can be maintained.

[0352] One corner of the arc grid rack (830) can be defined as the arc grid outer edge (840).

[0353] The outer edge of the arc grid (840) forms part of the inner edge of the second arc grid (800). The outer edge of the arc grid (840) can be defined as an inner edge among the edges of the arc grid rack (830).

[0354] In other words, the arc grid perimeter (840) can be defined as each corner where the first arc grid rack (831) and the second arc grid rack (832) face each other.

[0355] The outer circumference of the arc grid (840) may extend from one end in the height direction of the arc grid rack (830), i.e., the lower end, to the other end in the height direction, i.e., the upper end. At this time, the one end of the outer circumference of the arc grid (840), the upper end in the illustrated embodiment, may be continuous with the inner circumference of the arc grid (850).

[0356] The outer edge of the arc grid (840) may have a shape corresponding to the shape of the arc grid rack (830). In the illustrated embodiment, the outer edge of the arc grid (840) extends obliquely toward the inner and upper sides in the length direction of the second arc grid (800), i.e., the left and right directions. At this time, the outer edge of the arc grid (840) may include a rounded portion that is convex toward the inner side in the width direction of the second arc grid (800), i.e., the left and right directions.

[0357] As described above, the arc grid rack (830) may be provided as a pair including a first arc grid rack (831) and a second arc grid rack (832). Accordingly, the arc grid outer circumference (840) may also be defined to include a first arc grid outer circumference (841) which is one corner of the first arc grid rack (831) and a second arc grid outer circumference (842) which is one corner of the second arc grid rack (832).

[0358] The first arc grid outer circumference (841) forms one side of the first arc grid rack (831), the right corner in the illustrated embodiment. The first arc grid outer circumference (841) extends obliquely upward to the right from the lower end of the first arc grid rack (831) toward the first arc grid inner circumference (851). The first arc grid outer circumference (841) is continuous with the lower end of the first arc grid inner circumference (851).

[0359] The portion where the outer circumference (841) of the first arc grid is continuous with the inner circumference (851) of the first arc grid can be defined as a second projection (nw2). As described above, the second projection (nw2) can be formed in a pointed shape protruding outward.

[0360] That is, the upper end of the arc grid groove (860) according to the illustrated embodiment (or the third arc grid inner circumference (853) surrounding it) is positioned higher than the second center (oc2) where the extension line of the first arc grid outer circumference (841) and the extension line of the second arc grid outer circumference (842) meet.

[0361] Accordingly, the lower end of the arc grid inner circumference (850) surrounding the arc grid groove (860) is also positioned relatively high, so that the second projection (nw2) is positioned further upward. As a result, the generated arc reaches the second projection (nw2) after being extended by a longer length, so the arc can be extended to a length sufficient for extinguishing, thereby improving the arc extinguishing effect.

[0362] The second arc grid outer circumference (842) forms one side of the second arc grid rack (832), the left corner in the illustrated embodiment. The second arc grid outer circumference (842) extends obliquely to the upper left from the lower end of the second arc grid rack (832) toward the second arc grid inner circumference (852). The second arc grid outer circumference (842) is continuous with the lower end of the second arc grid inner circumference (852).

[0363] The second arc grid outer circumference (842) is spaced apart from the first arc grid outer circumference (841) along the length direction of the first arc grid outer circumference (841), and in the illustrated embodiment, the left-right direction, and is positioned to face the first arc grid outer circumference (841). A point where the extension line of the first arc grid outer circumference (841) and the extension line of the second arc grid outer circumference (842) meet each other can be defined as the second center (nc2).

[0364] At this time, the angle formed by the outer circumference of the first arc grid (841) and the outer circumference of the second arc grid (842) with respect to the second center (nc2) can be defined as the second angle (na2). The second angle (na2) can be formed to be smaller than the second angle (oa2) according to the above embodiment.

[0365] Accordingly, the first arc grid outer circumference (841) and the second arc grid outer circumference (842) can be formed to have a steeper slope compared to the first arc grid outer circumference (641) and the second arc grid outer circumference (642) described above.

[0366] The upper end of the outer circumference (840) of the arc grid is continuous with the inner circumference (850) of the arc grid.

[0367] The arc grid inner circumference (850) constitutes another part of the inner circumference of the arc grid body (810). The arc grid inner circumference (850) partially surrounds the arc grid groove (860) formed by being recessed inside the arc grid body (810).

[0368] In the illustrated embodiment, the arc grid inner circumference (850) surrounds the arc grid groove (860) on the upper, left, and right sides. That is, the arc grid inner circumference (850) can be defined as a part of the inner circumference of the arc grid body (810).

[0369] One side in the height direction of the arc grid inner circumference (850), the upper side in the illustrated embodiment, surrounds the upper end of the arc grid groove (860). The upper end of the arc grid groove (860) is enclosed and closed by the arc grid inner circumference (850). Additionally, the other side in the height direction of the arc grid inner circumference (850), the lower side in the illustrated embodiment, is continuous with the upper end of the arc grid outer circumference (840).

[0370] At this time, a second projection (nw2) may be formed in the part where the inner circumference (850) of the arc grid is continuous with the outer circumference (840) of the arc grid.

[0371] The arc grid inner circumference (850) is continuous with the arc grid outer circumference (840) and can be formed in any shape that can partially surround the arc grid groove (860). In the illustrated embodiment, the arc grid inner circumference (850) is configured to include a first arc grid inner circumference (851), a second arc grid inner circumference (852), and a third arc grid inner circumference (853).

[0372] The first arc grid inner circumference (851) forms a part of the arc grid inner circumference (850). The first arc grid inner circumference (851) surrounds the arc grid groove (860) on one side in the width direction, on the left side in the illustrated embodiment. The first arc grid inner circumference (851) extends in the height direction of the arc grid groove (860), in the vertical direction in the illustrated embodiment.

[0373] One side in the height direction of the first arc grid inner circumference (851), the lower end in the illustrated embodiment, is continuous with the first arc grid outer circumference (841). The portion where the first arc grid inner circumference (851) and the first arc grid outer circumference (841) are continuous can be defined as a second projection (nw2).

[0374] The other side in the height direction of the first arc grid inner circumference (851), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (853). A second center (nc2) may be located on the extension line of the first arc grid inner circumference (851).

[0375] That is, in the embodiment illustrated in FIG. 9, a second center (nc2) is positioned above the first arc grid inner circumference (851), so that the second center (oc2) is positioned further above the upper end of the first arc grid inner circumference (851).

[0376] The first arc grid inner circumference (851) is positioned to face the second arc grid inner circumference (852) with the arc grid groove (860) in between.

[0377] The second arc grid inner circumference (852) constitutes another part of the arc grid inner circumference (850). The second arc grid inner circumference (852) surrounds the arc grid groove (860) on the other side in the width direction, on the right side in the illustrated embodiment. The second arc grid inner circumference (852) extends in the height direction of the arc grid groove (860), in the vertical direction in the illustrated embodiment.

[0378] One side in the height direction of the inner circumference (852) of the second arc grid, the lower end in the illustrated embodiment, is continuous with the outer circumference (842) of the second arc grid. The inner circumference (852) of the second arc grid and the outer circumference (842) of the second arc grid may be continuous with each other at a predetermined angle. In the illustrated embodiment, the predetermined angle may be an obtuse angle.

[0379] The other side in the height direction of the second arc grid inner circumference (852), the upper end in the illustrated embodiment, is continuous with the third arc grid inner circumference (853). The second arc grid inner circumference (852) is continuous with one end in the extension direction of the third arc grid inner circumference (853), the right end in the illustrated embodiment.

[0380] The third arc grid inner circumference (853) constitutes the remainder of the arc grid inner circumference (850). The third arc grid inner circumference (853) surrounds the arc grid groove (860) on one side in the height direction, in the illustrated embodiment, on the upper side. The third arc grid inner circumference (853) extends in the width direction of the arc grid groove (860), in the left-right direction, in the illustrated embodiment.

[0381] At this time, the third arc grid inner circumference (853) may be rounded and extended convexly to one side in the height direction of the arc grid groove (860). In the illustrated embodiment, the third arc grid inner circumference (853) is rounded and extended convexly upward. Accordingly, it will be understood that the arc grid inner circumference (850) is formed in the shape of an inverted "U".

[0382] The third arc grid inner circumference (853) is continuous with the first arc grid inner circumference (851). One end of the third arc grid inner circumference (853) in the extension direction, the left end in the illustrated embodiment, is continuous with the upper end of the first arc grid inner circumference (851).

[0383] The third arc grid inner circumference (853) is continuous with the second arc grid inner circumference (852). The other end of the third arc grid inner circumference (853) in the extension direction, the right end in the illustrated embodiment, is continuous with the upper end of the second arc grid inner circumference (852).

[0384] Meanwhile, the vertical distance between the upper end of the third arc grid inner circumference (853) and the lower end of the second arc grid inner circumference (852) can be defined as the second depth (nd2). Alternatively, the second depth (nd2) can be defined as the distance between the upper end of the second arc grid outer circumference (842) and the upper end of the arc grid groove (860).

[0385] That is, it will be understood that the second depth (nd2) means the vertical length, i.e., the depth, of the arc grid groove (860).

[0386] At this time, the second depth (nd2) of the second arc grid (800) can be formed longer than the second depth (od2) of the second arc grid (600). That is, the arc grid groove (860) of the second arc grid (800) can be formed deeper than the arc grid groove (860) of the second arc grid (800). Accordingly, the elongation length of the generated arc is increased, and the arc extinguishing effect of the arc can also be improved.

[0387] The arc grid groove (860) is in communication with the space formed between the first arc grid rack (831) and the second arc grid rack (832), that is, the space where a movable contact (not shown) is located. The arc grid groove (860) provides a passage for an arc generated in the space to flow into the arc grid body (810).

[0388] The arc grid groove (860) is formed by being recessed inside the arc grid body (810). Specifically, the arc grid groove (860) is formed by being recessed on one side in the height direction of the arc grid body (810), at the lower end in the illustrated embodiment.

[0389] The arc grid groove (860) is partially enclosed by a part of the inner circumference of the arc grid body (810), namely the arc grid inner circumference (850). In the illustrated embodiment, each side in the width direction and one side in the height direction of the arc grid groove (860), namely the left, right, and upper sides, are enclosed by the arc grid inner circumference (850).

[0390] The other side in the height direction of the arc grid home (860), the lower side in the illustrated embodiment, is formed open and communicates with the space, that is, the space where the arc is generated.

[0391] The arc grid groove (860) may have a shape corresponding to the shape of the arc grid inner circumference (850). In the illustrated embodiment, the arc grid groove (860) is formed such that its vertical height is longer than its horizontal width, and its upper end is rounded so as to be convex outward.

[0392] At this time, the height of the arc grid groove (860), that is, the length in the vertical direction, can be defined as the second depth (nd2). As described above, the second depth (nd2) of the second arc grid (800) according to the present embodiment can be formed to be longer than the second depth (od2) of the second arc grid (600) according to the above embodiment.

[0393] Meanwhile, although not illustrated, the arc grid groove (860) may be formed to have a longer length and a narrower width. In the above embodiment, the upper end of the arc grid groove (860) is located higher than the second center (nc2).

[0394] In addition, in the above embodiment, the second angle (na2), which is the angle formed by the first arc grid rack (831) and the second arc grid rack (832), may be the same as the second angle (oa2) according to the above embodiment.

[0395]

[0396] Referring to FIGS. 10 to 13, a state in which a first arc guide (500, 700) and a second arc guide (600, 800) according to each embodiment of the present invention are overlapped is illustrated. By the illustrated state, the structural differences between the first arc guide (500, 700) and the second arc guide (600, 800) according to each embodiment can be more clearly understood.

[0397] Referring to FIGS. 10 and 11, the overlapping state of the first arc guide (500, 700) is illustrated as an example.

[0398] As described above, the first height (nh1), which is the height of the arc grid rack (730) provided in the first arc grid (700), is formed to be longer than the first height (oh1), which is the height of the arc grid rack (530) provided in the first arc grid (500).

[0399] Accordingly, the position of the first projection (nw1) where the first arc grid rack (731) and the first arc grid inner circumference (751) are continuous is positioned higher than the position of the first projection (ow1) where the first arc grid rack (531) and the first arc grid inner circumference (551) are continuous.

[0400] Therefore, the generated arc can be extended to a longer length compared to the case where it reaches the first projection (ow1) and reach the first projection (nw1).

[0401] Accordingly, the generated arc can be extended and separated (i.e., extinguished) in a portion of the first arc grid (700) that is higher than the first arc grid (500). That is, the generated arc can be easily extended to a portion of the first arc grid (700) that is higher, so that the arc extinguishing effect of the arc can be improved.

[0402] In particular, even in the case of a small current circuit breaker where it is difficult to generate sufficient pressure for arc extinguishing, the generated arc can extend to the upper part of the first arc grid (700). Accordingly, the arc extinguishing effect of the generated arc can be improved even in the case of a circuit breaker through which a small current is conducted.

[0403] Additionally, the first depth (nd1), which is the depth of the arc grid groove (760) formed in the first arc grid (700), may be formed longer than the first depth (od1), which is the depth of the arc grid groove (560) formed in the first arc grid (500). Accordingly, the upper end of the arc grid groove (760) is positioned higher than the upper end of the arc grid groove (560).

[0404] Therefore, the generated arc can be extended in the arc grid groove (760) by a longer length compared to when it is extended in the arc grid groove (560).

[0405] Meanwhile, the first center (oc1), which is the point where the extension line of the first arc grid outer circumference (541) and the extension line of the second arc grid outer circumference (542) meet, is located higher than the upper end of the arc grid groove (560).

[0406] On the other hand, the first center (nc1), which is the point where the extension line of the first arc grid outer circumference (741) and the extension line of the second arc grid outer circumference (742) meet, is located lower than the end of the arc grid groove (760). To this end, the arc grid rack (730) can be extended more steeply than the arc grid rack (530).

[0407] Additionally, as the arc grid rack (730) is extended more steeply, the size of the first angle (na1), which is the angle between the first arc grid rack (731) and the second arc grid rack (732) centered on the first center (nc1), may be smaller than the size of the first angle (oa1), which is the angle between the first arc grid rack (531) and the second arc grid rack (532) centered on the first center (oc1).

[0408] Accordingly, the arc generated between the first arc grid rack (731) and the second arc grid rack (732) can be extended by a longer length toward the first projection (nw1) and the arc grid groove (760). Thus, the length to which the arc is extended is increased, and the arc extinguishing effect of the arc can be improved.

[0409] Furthermore, as described above, the decrease in the area of ​​the arc grid body (710) is offset by the increase in the area of ​​the arc grid rack (730), so that the cooling effect of the arc can be maintained.

[0410] Referring to FIGS. 12 and 13, an overlapping state of the second arc guide (600, 800) is illustrated as an example.

[0411] As described above, the second height (nh2), which is the height of the arc grid rack (830) provided in the second arc grid (800), is formed to be longer than the second height (oh2), which is the height of the arc grid rack (630) provided in the second arc grid (600).

[0412] Accordingly, the position of the second projection (nw2) where the first arc grid rack (831) and the first arc grid inner circumference (851) are connected is positioned higher than the position of the second projection (ow2) where the first arc grid rack (631) and the first arc grid inner circumference (651) are connected.

[0413] Therefore, the generated arc can be extended to a longer length than when it reaches the second projection (ow2) and reach the second projection (nw2).

[0414] Accordingly, the generated arc can be extended and separated (i.e., extinguished) in a portion of the second arc grid (800) that is higher than the second arc grid (600). That is, the generated arc can be easily extended to a portion of the second arc grid (800) that is higher, so that the arc extinguishing effect of the arc can be improved.

[0415] In particular, even in the case of a small current circuit breaker where it is difficult to generate sufficient pressure for arc extinguishing, the generated arc can extend to the upper part of the second arc grid (800). Accordingly, the arc extinguishing effect of the generated arc can be improved even in the case of a circuit breaker through which a small current is conducted.

[0416] Additionally, the second depth (nd2), which is the depth of the arc grid groove (860) formed in the second arc grid (800), may be formed longer than the second depth (od2), which is the depth of the arc grid groove (660) formed in the second arc grid (600). Accordingly, the upper end of the arc grid groove (860) is positioned higher than the upper end of the arc grid groove (660).

[0417] Therefore, the generated arc can be extended in the arc grid groove (860) by a longer length compared to when it is extended in the arc grid groove (660).

[0418] Meanwhile, the second center (oc2), which is the point where the extension line of the first arc grid outer circumference (641) and the extension line of the second arc grid outer circumference (642) meet, is located higher than the upper end of the arc grid groove (660).

[0419] On the other hand, the second center (oc2), which is the point where the extension line of the first arc grid outer circumference (841) and the extension line of the second arc grid outer circumference (842) meet, is located lower than the end of the arc grid groove (860). To this end, the arc grid rack (830) can be extended more steeply than the arc grid rack (630).

[0420] Additionally, as the arc grid rack (830) is extended more steeply, the size of the second angle (na2), which is the angle between the first arc grid rack (831) and the second arc grid rack (832) centered on the second center (nc2), may be smaller than the size of the second angle (oa2), which is the angle between the first arc grid rack (631) and the second arc grid rack (632) centered on the second center (oc2).

[0421] Accordingly, the arc generated between the first arc grid rack (831) and the second arc grid rack (832) can be extended by a longer length toward the second projection (nw2) and the arc grid groove (860). Thus, the length to which the arc is extended is increased, and the arc extinguishing effect of the arc can be improved.

[0422] Furthermore, as described above, the decrease in the area of ​​the arc grid body (810) is offset by the increase in the area of ​​the arc grid rack (830), so that the cooling effect of the arc can be maintained.

[0423]

[0424] Although embodiments of the present invention have been described, the spirit of the present invention is not limited to the embodiments presented in this specification. Those skilled in the art who understand the spirit of the present invention may easily propose other embodiments within the scope of the same spirit by adding, changing, deleting, or adding components, and such embodiments shall also be considered to fall within the scope of the spirit of the present invention.

[0425] 10: Arc Soaring Mechanism 100: Arc Soaring Frame

[0426] 200: Arc Soh side plate 210: 1st Arc Soh side plate

[0427] 220: 2nd Arc Soho Side Plate 300: Arc Runner

[0428] 400: Arc Guide 410: First Arc Guide

[0429] 420: 2nd Arc Guide 500: 1st Arc Grid

[0430] 510: Arc Grid Body 520: Arc Grid Head

[0431] 530: Arc Grid Lag 531: 1st Arc Grid Lag

[0432] 532: 2nd Arc Grid Rack 540: Arc Grid Outsourcing

[0433] 541: 1st Arc Grid Outsourcing 542: 2nd Arc Grid Outsourcing

[0434] 550: Arc Grid Inner Palace 551: 1st Arc Grid Inner Palace

[0435] 552: 2nd Arc Grid In-place 553: 3rd Arc Grid In-place

[0436] 560: Arc Grid Home 600: 2nd Arc Grid

[0437] 610: Arc Grid Body 620: Arc Grid Head

[0438] 630: Arc Grid Lag 631: 1st Arc Grid Lag

[0439] 632: 2nd Arc Grid Rack 640: Arc Grid Outsourcing

[0440] 641: 1st Arc Grid Outsourcing 642: 2nd Arc Grid Outsourcing

[0441] 650: Arc Grid Inner Palace 651: 1st Arc Grid Inner Palace

[0442] 652: 2nd Arc Grid In-house 653: 3rd Arc Grid In-house

[0443] 660: Arc Grid Home 700: 1st Arc Grid

[0444] 710: Arc Grid Body 720: Arc Grid Head

[0445] 730: Arc Grid Lag 731: 1st Arc Grid Lag

[0446] 732: 2nd Arc Grid Rack 740: Arc Grid Outsourcing

[0447] 741: 1st Arc Grid Outsourcing 742: 2nd Arc Grid Outsourcing

[0448] 750: Arc Grid Inner Palace 751: 1st Arc Grid Inner Palace

[0449] 752: 2nd Arc Grid In-place 753: 3rd Arc Grid In-place

[0450] 760: Arc Grid Home 800: 2nd Arc Grid

[0451] 810: Arc Grid Body 820: Arc Grid Head

[0452] 830: Arc Grid Lag 831: 1st Arc Grid Lag

[0453] 832: 2nd Arc Grid Rack 840: Arc Grid Outsourcing

[0454] 841: 1st Arc Grid Outsourcing 842: 2nd Arc Grid Outsourcing

[0455] 850: Arc Grid Inner Palace 851: 1st Arc Grid Inner Palace

[0456] 852: 2nd Arc Grid In-place 853: 3rd Arc Grid In-place

[0457] 860: Arc Grid Home od1, nd1: 1st Depth

[0458] od2, nd2: 2nd depth oa1, na1: 1st angle

[0459] oa2, na2: Second angle oc1, nc1: First center

[0460] oc2, nc2: Second center ow1, nw1: First projection

[0461] ow2, nw2: Second projection oh1, nh1: First height

[0462] oh2, nh2: Second height

[0463]

Claims

1. Plate-shaped arc grid body; A pair of arc grid racks extending from one end in the height direction of the above arc grid body; A pair of arc grid outer peripheries constituting the inner corners of each of the pair of arc grid racks; and It includes an arc grid groove positioned between a pair of the arc grid racks and formed by a recess at one end of the arc grid body, A pair of the outer peripheries of the aforementioned arc grids extend obliquely toward the arc grid grooves and each other, forming a predetermined angle with respect to the height direction of the arc grid body, and The height-direction end of the above arc grid groove is positioned higher than a point where a pair of extension lines of the outer circumference of the arc grid meet. Arc Grid.

2. In Paragraph 1, The above arc grid rack is, A first arc grid rack located on one side in the longitudinal direction of the above arc grid body; and It includes a second arc grid rack located on the other side in the longitudinal direction of the arc grid body, and The above arc grid outsourcing is, A first arc grid outer circumference forming the inner corner of the first arc grid rack and extending obliquely toward the arc grid groove; and Constituting the inner corner of the second arc grid rack and including the outer circumference of the second arc grid that extends obliquely toward the arc grid groove, Arc Grid.

3. In Paragraph 1, Defined by the inner edge of the arc grid body, it includes an arc grid inner circumference that partially surrounds the arc grid groove, and A projection protruding outward is formed in a continuous portion where the inner circumference of the arc grid and the outer circumference of the arc grid are connected. Arc Grid.

4. In Paragraph 3, The above arc grid provides, A first arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on one side in the width direction; A second arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on the other side in the width direction; and A third arc grid inner circumference that is continuous with the first arc grid inner circumference and the second arc grid inner circumference, respectively, and surrounds the end of the arc grid groove, Arc Grid.

5. In Paragraph 4, The above-mentioned point where the extension lines of the outer circumference of a pair of the above-mentioned arc grids meet is, Located between the projection and the inner circumference of the third arc grid along the height direction of the arc grid body, Arc Grid.

6. In Paragraph 4, The above-mentioned point where the extension lines of the outer circumference of a pair of the above-mentioned arc grids meet is, Located on the inner circumference of the first arc grid, Arc Grid.

7. Multiple arc grids formed in a plate shape and spaced apart and arranged parallel to each other along the thickness direction; An arc extinguishing frame coupled to one side in the height direction of a plurality of the above-mentioned arc grids; and It includes an arc guide coupled to the other side in the height direction of a plurality of the above-mentioned arc grids, and The above arc grid is, Plate-shaped arc grid body; A pair of arc grid racks extending from one end in the height direction of the above arc grid body; and It includes an arc grid groove positioned between a pair of the arc grid racks and formed by a recess at one end of the arc grid body, The height-direction end of the above-mentioned arc grid groove is positioned higher than a point where the extensions of the inner edges of a pair of the above-mentioned arc grid racks meet. Arc Soho device.

8. In Paragraph 7, The above arc guide is, A first arc guide located on one side of the separation direction; and It includes a second arc guide located on the other side of the separation direction, The height of the first arc guide is formed to be longer than the height of the second arc guide. Arc Soho device.

9. In Paragraph 7, The above arc guide is, A pair of arc grid peripheries constituting the corners of a pair of arc grid racks; and It includes an arc grid inner circumference that surrounds the above arc grid groove and is continuous with the outer circumference of the arc grid, One end of the height direction of the inner circumference of the arc grid is positioned higher than the one point where the extension lines of a pair of the inner circumferences of the arc grid meet. Arc Soho device.

10. In Paragraph 9, A first arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on one side in the width direction; A second arc grid inner circumference extending in the height direction of the arc grid body, continuous with the outer circumference of the arc grid, and surrounding the arc grid groove on the other side in the width direction; and A third arc grid inner circumference that is continuous with the first arc grid inner circumference and the second arc grid inner circumference, respectively, and surrounds the end of the arc grid groove, Arc Soho device.

11. In Paragraph 10, The one point where the extension lines of a pair of the inner circumferences of the arc grid meet is located on the inner circumference of the first arc grid, Arc Soho device.

12. In Paragraph 10, The above arc grid rack is, A first arc grid rack located on one side in the longitudinal direction of the arc grid body; and It includes a second arc grid rack located on the other side in the longitudinal direction of the arc grid body, and The above arc grid outsourcing is, A first arc grid outer circumference forming the inner corner of the first arc grid rack and extending obliquely toward the arc grid groove; and Constituting the inner corner of the second arc grid rack and including the outer circumference of the second arc grid that extends obliquely toward the arc grid groove, Arc Soho device.

13. In Paragraph 12, The portion where the outer circumference of the first arc grid and the inner circumference of the first arc grid are continuous is located higher than the portion where the outer circumference of the second arc grid and the inner circumference of the second arc grid are continuous. Arc Soho device.

Images