Air circuit breaker

Abstract

An air circuit breaker is disclosed. The air circuit breaker of the present embodiment includes a cover magnet portion. The cover magnet portion is directly combined with an upper cover that forms the appearance of the air circuit breaker. The cover magnet portion is positioned adjacent to a fixed contact and forms a magnetic field. By the formed magnetic field, an electric arc generated is subjected to an electromagnetic force in the direction of an arc extinguishing portion. Thus, the electric arc generated can be rapidly moved and extinguished. The cover magnet portion is inserted into the face of the upper cover without being exposed to the outside. Thus, the electric arc generated does not come into contact with the cover magnet portion. As a result, the cover magnet portion is not damaged by the electric arc generated.

Description

TECHNICAL FIELD

[0001] The present application relates to an air circuit breaker, and more particularly, to an air circuit breaker having a structure capable of effectively extinguishing an arc generated by current interruption. BACKGROUND

[0002] A circuit breaker is a device capable of allowing or prohibiting energization with the outside by contact and separation of a fixed contact and a movable contact. The fixed contact and the movable contact provided to the circuit breaker are electrically connectable with an external power source or a load.

[0003] The movable contact is movably provided to the circuit breaker. The movable contact can be moved in a direction toward the fixed contact or a direction away from the fixed contact. If the movable contact and the fixed contact are in contact, the circuit breaker can be electrically connected with the external power source or the load.

[0004] When an overcurrent or an abnormal current flows in the circuit breaker, the movable contact and the fixed contact in contact with each other are separated from each other. At this time, the current flowing between the movable contact and the fixed contact is not immediately extinguished, but is transformed into the form of an arc and extends along the movable contact.

[0005] The arc can be defined as the flow of electrons of high temperature and high pressure. Therefore, in the case where the generated arc remains in the internal space of the circuit breaker for a long time, there is a risk that each constituent element of the circuit breaker is damaged. In addition, in the case where the arc is directly discharged to the outside of the circuit breaker without undergoing a separate treatment process, there is a risk that a user is injured.

[0006] In this regard, an arc extinguishing device for extinguishing and discharging the arc is generally provided in the circuit breaker. The generated arc passes through the arc extinguishing device, the arc pressure increases, the moving speed becomes fast, and at the same time, the arc is cooled, and then is discharged to the outside.

[0007] Therefore, it is necessary to quickly guide the generated arc to the arc extinguishing device.

[0008] Korean Patent Laid-Open Publication No. 10-2015-0001499 discloses a circuit breaker of a gas insulated opening and closing device in which arc energy utilization efficiency is improved. Specifically, a puffer type circuit breaker in which arc energy is used to increase the pressure of arc extinguishing gas, thereby improving arc extinguishing performance is disclosed.

[0009] However, this type of circuit breaker has a limitation that it can be applied only to a circuit breaker having additional gas as a medium for arc extinguishing. That is, the existing document can be used only in the case where SF6 (Sulfur hexafluoride) is used as a medium for arc extinguishing, and has a limitation that it is difficult to be applied to an air circuit breaker using air as a medium.

[0010] Korean Patent Publication Utility Model No. 20-100000825 discloses a current limiting structure of an air circuit breaker. Specifically, a current limiting structure of an air circuit breaker is disclosed, the air circuit breaker including a grid in which an arc chamber is laminated to have a prescribed gap, a guide groove being formed to position a contact; and a grid plate provided to a side wall of the guide groove of the grid.

[0011] However, this type of circuit breaker, although it can direct the arc to the grid by the guide plate, does not suggest a scheme for forming a path for the arc not flowing to the guide plate. That is, the prior art has a limitation in that a scheme for effectively forming a path for the arc not adjacent to the guide plate is not considered. SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] An object of the present invention is to provide an air circuit breaker of a structure capable of solving the above problems.

[0014] First, an object of the present invention is to provide an air circuit breaker of a structure capable of rapidly extinguishing and moving an arc generated

[0015] Further, an object of the present invention is to provide an air circuit breaker of a structure capable of easily disposing a magnet forming a magnetic field associated with a movement path of an arc.

[0016] Further, an object of the present invention is to provide an air circuit breaker of a structure capable of maintaining a stable combined state of a magnet forming a magnetic field associated with a movement path of an arc.

[0017] Further, an object of the present invention is to provide an air circuit breaker of a structure in which a magnet forming a magnetic field associated with a movement path of an arc is not damaged by an arc.

[0018] Further, an object of the present invention is to provide an air circuit breaker of a structure in which a magnet forming a magnetic field associated with a movement path of an arc is not damaged by an arc.

[0019] Further, an object of the present invention is to provide an air circuit breaker of a structure in which a magnet forming a magnetic field associated with a movement path of an arc is not damaged by an arc.

[0020] TECHNICAL SOLUTION TO THE PROBLEMS

[0021] To achieve the above object, the present application provides an air circuit breaker including: an upper cover in which a space is formed; a fixed contact accommodated in the space of the upper cover; a movable contact accommodated in the space of the upper cover, located adjacent to the fixed contact, and moved in a direction toward or away from the fixed contact; an arc extinguishing part accommodated in the space of the upper cover, located adjacent to the fixed contact, and extinguishing an arc extending from the fixed contact toward the movable contact; and a cover magnet part combined with the upper cover, located adjacent to the fixed contact, and forming a magnetic field in which an electromagnetic force is applied to the arc.

[0022] In addition, the cover magnet part of the air circuit breaker can be configured to surround the fixed contact on one side of the fixed contact or on the other side of the fixed contact opposite to the one side.

[0023] In addition, the fixed contact of the air circuit breaker can be provided in plural, the plural fixed contacts can be configured to be spaced apart from each other in one direction, the cover magnet part can be provided in plural, the plural cover magnet parts can be configured to be spaced apart from each other in the one direction, and the plural fixed contacts can be respectively configured between the cover magnet parts adjacent to each other among the plural cover magnet parts.

[0024] In addition, the upper side surfaces of the plural cover magnet parts of the air circuit breaker can be magnetized to have the same polarity as each other.

[0025] In addition, the upper cover of the air circuit breaker includes: a first upper cover covering the fixed contact on the side of the fixed contact opposite to the movable contact, in which a space is formed to accommodate a part of the arc extinguishing part and the fixed contact; and a second upper cover combined with the first upper cover, located on the other side of the fixed contact toward the movable contact, in which a space is formed to accommodate the remaining part of the arc extinguishing part and the movable contact; and the cover magnet part can be combined with any one of the first upper cover and the second upper cover, and extend toward the remaining one of the first upper cover and the second upper cover.

[0026] In addition, the upper cover of the air circuit breaker can be formed to extend in one direction, and both end parts of the one direction of the upper cover can surround the fixed contact.

[0027] In addition, the fixed contact of the air circuit breaker can be provided in plural, the plural fixed contacts can be configured to be spaced apart from each other in the one direction, the cover magnet part can be provided in plural, and the plural cover magnet parts can be respectively configured between the both end parts of the upper cover and the plural fixed contacts.

[0028] In addition, the fixed contact of the air circuit breaker can be provided with three, the three fixed contacts can be arranged apart from each other in the direction, the cover magnet portion can include: a first cover magnet located at a side end of the upper cover in the direction; a second cover magnet arranged opposite the first cover magnet across any one of the fixed contacts arranged on the one side in the direction among the three fixed contacts; a third cover magnet arranged opposite the second cover magnet across another one of the fixed contacts arranged in the middle in the direction among the three fixed contacts; and a fourth cover magnet arranged opposite the third cover magnet across the remaining one of the fixed contacts arranged on the other side in the direction among the three fixed contacts.

[0029] In addition, the upper side surfaces of the first cover magnet, the second cover magnet, the third cover magnet, and the fourth cover magnet of the air circuit breaker can be magnetized to S poles, respectively.

[0030] In addition, the present application provides an air circuit breaker including: an upper cover having a space formed therein; a fixed contact accommodated in the space of the upper cover; a movable contact rotatably accommodated in the space of the upper cover, located at a rear side of the fixed contact, and in contact with or separated from the fixed contact; an arc extinguishing portion accommodated in the space of the upper cover, located at an upper side of the fixed contact, and configured to extinguish an arc generated between the fixed contact and the movable contact; and a cover magnet portion combined with the upper cover, located at a left side of the fixed contact or a right side of the fixed contact, and configured to form a magnetic field applying an electromagnetic force to the arc.

[0031] In addition, the fixed contact of the air circuit breaker can be provided with a plurality of fixed contacts arranged apart from each other in the left-right direction, the cover magnet portion can be provided with a plurality of cover magnet portions, and the plurality of cover magnet portions can be arranged at a left side of a leftmost one of the plurality of fixed contacts, a right side of a rightmost one of the plurality of fixed contacts, and between the plurality of fixed contacts, respectively.

[0032] In addition, the upper side surfaces of the plurality of cover magnet portions of the air circuit breaker can be magnetized to the same polarity.

[0033] Additionally, the upper cover of the air circuit breaker can extend in a left-right direction, and three fixed contacts can be provided, which are spaced apart from each other in the left-right direction within the interior space of the upper cover. The cover magnet portion can include: a first cover magnet, which is attached to the upper cover to the left of the leftmost fixed contact; a second cover magnet, which is attached to the upper cover to the right of the leftmost fixed contact; a third cover magnet, which is attached to the upper cover to the right of the central fixed contact; and a fourth cover magnet, which is attached to the upper cover to the right of the rightmost fixed contact.

[0034] In addition, the upper surfaces of the first cover magnet, the second cover magnet, the third cover magnet, and the fourth cover magnet of the air circuit breaker can be magnetized into S poles, respectively.

[0035] Additionally, the upper cover of the air circuit breaker may include: a first upper cover covering the fixed contact on the side opposite to the movable contact, forming a space inside to accommodate a portion of the arc-extinguishing section and the fixed contact; and a second upper cover, coupled to the first upper cover, located on the other side of the fixed contact facing the movable contact, forming a space inside to accommodate the remaining portion of the arc-extinguishing section and the movable contact; the cover magnet portion may be coupled to either the first upper cover or the second upper cover, and extends toward the remaining one of the first upper cover and the second upper cover.

[0036] Invention Effects

[0037] According to various embodiments of the present invention, the following effects can be achieved.

[0038] First, the air circuit breaker is equipped with a cover magnet section. The cover magnet section is located near the fixed contacts and movable contacts where current flows. In addition, the cover magnet section is located near the arc-extinguishing section that extinguishes the arc generated when the fixed contacts and movable contacts separate.

[0039] The magnetic field generated by the magnet can span the fixed contact, the movable contact, and the arc-extinguishing part. When the fixed contact and the movable contact are separated, the magnetic field generates an electromagnetic force. The generated electromagnetic force forms in the direction towards the arc-extinguishing part.

[0040] As a result, the generated electric arc is drawn towards the arc-extinguishing part by the magnetic field formed by the cover magnet. Therefore, the generated electric arc can be moved quickly and extinguished.

[0041] In addition, the cover magnet portion is combined with the cover portion, specifically, an upper cover. The upper cover forms the appearance of the air circuit breaker, and has a space formed therein so as to be able to accommodate a fixed contact, a movable contact, and an arc extinguishing portion, etc. In an embodiment, a groove for allowing the cover magnet portion to be inserted and combined can be formed in the upper cover.

[0042] That is, no additional fastening member or the like for allowing the cover magnet portion that forms a magnetic field to be positioned in the inner space of the upper cover is required. In addition, by merely inserting and combining the cover magnet portion in the groove formed in the upper cover, the cover magnet portion can be provided to the air circuit breaker.

[0043] Thus, it is easy to combine the cover magnet portion for forming the moving path of the electric arc to the air circuit breaker.

[0044] In addition, the upper cover can be composed of a first upper cover provided to the front side and a second upper cover provided to the rear side. The cover magnet portion can be inserted and combined in any one of the first upper cover and the second upper cover. The other one of the first upper cover and the second upper cover can have a groove formed therein so that the remaining portion of the cover magnet portion can be inserted.

[0045] Thus, in the case where the first upper cover and the second upper cover are combined and fastened, the cover magnet portion is inserted into the grooves formed in the first upper cover and the second upper cover, respectively. As a result, the cover magnet portion can be stably combined to the upper cover.

[0046] In addition, by the above-described structure, the cover magnet portion is not exposed to the outside due to the upper cover. That is, even in the case where an electric arc is generated in the inner space of the upper cover, the generated electric arc does not reach the cover magnet portion.

[0047] Thus, the cover magnet portion is not damaged by the generated electric arc.

[0048] In addition, the cover magnet portion is directly combined with the upper cover. That is, no additional combining member or fastening member required in the case where the cover magnet portion is accommodated in the inner space of the upper cover is required any more.

[0049] Therefore, no excessive design change is required in order to provide the cover magnet portion.

[0050] Further, the cover magnet portion is directly combined to the frame that forms the upper cover. Therefore, even if no additional space is secured, the cover magnet portion can be provided.

[0051] Therefore, even if the cover magnet portion is provided, no excessive space is occupied. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 is a perspective view showing an air circuit breaker according to an embodiment of the present application.

[0053] Figure 2 is a view showing a cross section of the air circuit breaker shown inFigure 1 A 3D view of an air circuit breaker with the back cover removed.

[0054] Figure 3 It shows from Figure 1 Front view of the air circuit breaker with the back cover removed.

[0055] Figure 4 It shows from Figure 1 A top view of an air circuit breaker with the back cover removed.

[0056] Figure 5 It shows from Figure 1 A cross-sectional view of an air circuit breaker with the back cover removed.

[0057] Figure 6 It shows the setting in Figure 1 A three-dimensional diagram of the permanent magnet of an air circuit breaker.

[0058] Figure 7 It shows the setting in Figure 1 Front view of the permanent magnet of an air circuit breaker.

[0059] Figure 8 It shows the setting in Figure 1 An exploded perspective view of the current transformer housing of an air circuit breaker.

[0060] Figure 9 It is shown Figure 8 Front view of the current transformer housing.

[0061] Figure 10 It shows the setting in Figure 1 A perspective view of an embodiment of the arc-extinguishing section of an air circuit breaker.

[0062] Figure 11 It is shown Figure 10 A front view of one embodiment of the arc-extinguishing unit shown.

[0063] Figure 12 It is shown Figure 10 A top view of one embodiment of the arc-extinguishing section shown.

[0064] Figure 13 It is shown Figure 10 A side view of one embodiment of the arc-extinguishing unit shown.

[0065] Figure 14 It shows from Figure 10 The diagram shows the state of the arc-extinguishing section with the arc cover disassembled.

[0066] Figure 15 It shows from Figure 14 A three-dimensional view showing the state of the disassembled grid section of the arc-extinguishing part.

[0067] Figure 16 It shows from Figure 14 The top view shows the state of the arc-extinguishing section after the mesh section has been disassembled.

[0068] Figure 17 It shows from Figure 15 The diagram shows the state of the upper magnet part of the arc-extinguishing section after disassembly.

[0069] Figure 18 It shows from Figure 15 The top view shows the state of the upper magnet part of the arc extinguishing unit after it has been removed.

[0070] Figure 19 It shows the setting in Figure 1 A perspective view of another embodiment of the arc-extinguishing section of an air circuit breaker.

[0071] Figure 20 It shows the setting in Figure 1 A front view of another embodiment of the arc-extinguishing section of an air circuit breaker.

[0072] Figure 21 It shows from Figure 19 A three-dimensional view showing the state of the arc-extinguishing section after the support plate has been removed.

[0073] Figure 22 It shows from Figure 19 The front view shows the state of the arc-extinguishing section with the support plate removed.

[0074] Figure 23 It shows from Figure 19 The image shows a bottom view of the arc-extinguishing section with the support plate removed.

[0075] Figure 24 It shows from Figure 19 The image shown is a three-dimensional view of the arc-extinguishing section with a portion of the grille removed.

[0076] Figure 25 It shows from Figure 19 The front view shows the state of the arc-extinguishing section with a portion of the grille removed.

[0077] Figure 26 It shows from Figure 19 The left view (a) and right view (b) show the state of the arc-extinguishing section with a portion of the grille removed.

[0078] Figure 27 It shows the setting in Figure 19 An exploded perspective view of the arc-extinguishing magnet section of the arc-extinguishing unit is shown.

[0079] Figure 28 This is shown from another angle as the setting Figure 19An exploded perspective view of the arc-extinguishing magnet section of the arc-extinguishing unit is shown.

[0080] Figure 29 It shows the setting in Figure 19 The front view of the arc-extinguishing magnet section of the arc-extinguishing unit shown.

[0081] Figure 30 It shows the setting in Figure 19 The top view of the arc-extinguishing magnet section of the arc-extinguishing unit shown.

[0082] Figure 31 This is a front view illustrating an example of a magnetic field formed in a frame and the path of an electric arc formed according to the magnetic field, as per an embodiment of the present invention.

[0083] Figure 32 This is a top view illustrating an example of a magnetic field formed in a frame and the path of an electric arc formed according to the magnetic field, according to an embodiment of the present invention.

[0084] Figure 33 It is shown in Figure 10 A front view of an example of the magnetic field formed by the arc-extinguishing section of the embodiment and the path of the electric arc formed according to the magnetic field.

[0085] Figure 34 It is shown in Figure 10 A cross-sectional view of an example of the magnetic field formed by the arc-extinguishing section of the embodiment and the path of the arc formed according to the magnetic field.

[0086] Figure 35 It is shown in Figure 10 A front view of an example of the magnetic field formed by the arc-extinguishing section of the embodiment and the path of the electric arc formed according to the magnetic field.

[0087] Figure 36 It is shown in Figure 10 A cross-sectional view of the magnetic field formed by the arc-extinguishing part of the embodiment and another example of the path of the arc formed according to the magnetic field.

[0088] Figure 37 It is shown in including Figure 8 The current transformer housing and Figure 10 A cross-sectional view of an example of the magnetic field generated by the air circuit breaker of the arc-extinguishing section of the embodiment and the path of the arc generated therefrom.

[0089] Figure 38 It is shown in including Figure 8 The current transformer housing and Figure 10 A front view of another example of the magnetic field formed by the air circuit breaker of the arc-extinguishing section of the embodiment and the path of the arc formed thereunder.

[0090] Figure 39 It is shown in including Figure 8 The current transformer housing andFigure 10 A front view of an example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same.

[0091] Figure 40 A front view of an example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 8 A sectional view of an example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 10

[0092] Figure 41 A front view of an example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 19

[0093] Figure 42 A bottom view of an example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 19

[0094] Figure 43 A front view of another example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 19

[0095] A bottom view of another example of a magnetic field formed by an arc extinguishing portion of an air circuit breaker according to an embodiment of the present application and a path of an arc formed according to the same. Figure 44 DETAILED DESCRIPTION Figure 19 Hereinafter, an arc extinguishing portion according to an embodiment of the present application and an air circuit breaker including the same will be described in detail with reference to the accompanying drawings.

[0096] In the following description, explanation about a part of constituent elements can be omitted in order to clarify the features of the present application.

[0097] In the following description, "current conduction" means that a current or an electric signal is transmitted between two or more components.

[0098] 1. Definition of terms

[0099] In the following description, "magnet" means any object that can magnetize a magnetic body or generate a magnetic field. In an embodiment, the magnet can be a permanent magnet or an electromagnet.

[0100] In the following description, "magnet" means any object that can magnetize a magnetic body or generate a magnetic field. In an embodiment, the magnet can be a permanent magnet or an electromagnet.

[0101] ​​​​In the following description, the "air circuit breaker" refers to a circuit breaker that uses air or compressed air to extinguish an arc. Each of the configurations described below is premised on being applied to an air circuit breaker.

[0102] However, each of the configurations described below can also be applied to an air circuit breaker, a compressed air circuit breaker, a gas circuit breaker, an oil circuit breaker, a vacuum circuit breaker, and the like.

[0103] In the following description, the term "main magnetic field" refers to a magnetic field formed between a plurality of magnets arranged adjacent to each other. That is, the main magnetic field M.M.F refers to a magnetic field formed from any one of the plurality of magnets toward another.

[0104] In the following description, the term "sub magnetic field" refers to a magnetic field formed by any one magnet itself. That is, the sub magnetic field S.M.F refers to a magnetic field formed from one side of any one magnet toward the other side.

[0105] In the following description, the terms "upper side", "lower side", "right side", "left side", "front side", and "rear side" can be understood with reference to the coordinate system shown in Figure 1

[0106] 2. Explanation of the structure of the air circuit breaker 10 according to the embodiment of the present application

[0107] Referring to Figures 1 to 5 , the air circuit breaker 10 of the embodiment of the present application includes a cover portion 100, a drive portion 200, and a breaking portion 300.

[0108] In addition, referring to Figures 6 to 30 , the air circuit breaker 10 of the embodiment of the present application includes a cover magnet portion 400, a CT (Current Transformer) magnet portion 500, and arc extinguishing portions 600, 700.

[0109] Hereinafter, each of the configurations of the air circuit breaker 10 of the embodiment of the present application will be described with reference to the accompanying drawings, and the cover magnet portion 400, the CT magnet portion 500, and the arc extinguishing portions 600, 700 will be described separately.

[0110] (1) Explanation of the cover portion 100

[0111] Referring to Figures 1 to 5 , the air circuit breaker 10 of the embodiment of the present application includes a cover portion 100.

[0112] ​The cover portion 100 forms the appearance of the air circuit breaker 10. In addition, a space is formed in the inside of the cover portion 100, and various constituent elements for the operation of the air circuit breaker 10 can be installed in the space.

[0113] That is, the cover portion 100 functions as a kind of housing.

[0114] The cover portion 100 can be formed of a material having high heat resistance and high rigidity. This is to prevent the various constituent elements installed in the inside from being damaged, and to prevent damage due to an arc generated in the inside. In an embodiment, the cover portion 100 can be formed of synthetic resin or reinforced plastic.

[0115] In the illustrated embodiment, the cover portion 100 has a quadrangular prism shape having the vertical direction as the height. The shape of the cover portion 100 can be formed in any shape that can install the constituent elements for the operation of the air circuit breaker 10 in the inside.

[0116] The inside space of the cover portion 100 is electrically connected to the outside. The various constituent elements installed in the inside of the cover portion 100 can be electrically connectable to the power source or the load of the outside.

[0117] In the illustrated embodiment, the cover portion 100 includes an upper cover 110 and a lower cover 120.

[0118] The upper cover 110 forms the upper side of the cover portion 100. The upper cover 110 is positioned on the upper side of the lower cover 120. In an embodiment, the upper cover 110 and the lower cover 120 can be formed in one body.

[0119] A space is formed in the inside of the upper cover 110. Various constituent elements provided in the air circuit breaker 10 are installed in the space. In an embodiment, the inside space of the upper cover 110 can install the breaking portion 300 and the arc extinguishing portions 600, 700, etc.

[0120] The inside space of the upper cover 110 is in communication with the inside space of the lower cover 120. The constituent elements such as the breaking portion 300 can be accommodated across the inside space of the upper cover 110 and the inside space of the lower cover 120.

[0121] The arc extinguishing portions 600, 700 are positioned on one side of the upper cover 110, and in the illustrated embodiment, on the upper side. A part of the arc extinguishing portions 600, 700 can be exposed on the upper side of the upper cover 110. An arc generated in the inside space of the upper cover 110 can be extinguished after passing through the arc extinguishing portions 600, 700, and then discharged to the outside of the air circuit breaker 10.

[0122] The fixed contact 310 of the disconnecting portion 300 is exposed on the other side of the upper cover 110, which is the front side in the illustrated embodiment. The fixed contact 310 can be electrically connected to an external power source or load through the exposed portion.

[0123] In the illustrated embodiment, the upper cover 110 includes a first upper cover 111 and a second upper cover 112.

[0124] The first upper cover 111 is configured to cover one side of the upper side of the air circuit breaker 10, which is the front side in the illustrated embodiment. The first upper cover 111 is coupled to the second upper cover 112 by any fastening member.

[0125] An opening portion is formed in the first upper cover 111. The fixed contact 310 can be exposed to the outside through the opening portion. In the illustrated embodiment, three opening portions are formed in the left-right direction.

[0126] A cover magnet portion 400 can be provided in the first upper cover 111. The cover magnet portion 400 can be provided in a direction in which the arc extinguishing portions 600, 700 are spaced apart from each other.

[0127] The second upper cover 112 is configured to cover the other side of the upper side of the air circuit breaker 10, which is the rear side in the illustrated embodiment. The second upper cover 112 can be coupled to the first upper cover 111 by any fastening member.

[0128] A cover magnet portion 400 can be provided in the second upper cover 112. As described above, a cover magnet portion 400 can also be provided in the first upper cover 111. That is, a cover magnet portion 400 can be provided in either the first upper cover 111 or the second upper cover 112.

[0129] The lower cover 120 forms the lower side of the cover portion 100. The lower cover 120 is positioned below the upper cover 110.

[0130] A space is formed in the inside of the lower cover 120. Various constituent elements provided in the air circuit breaker 10 are installed in the space. In one embodiment, the drive portion 200 and the disconnecting portion 300, etc. can be installed in the inside space of the lower cover 120.

[0131] The inside space of the lower cover 120 communicates with the inside space of the upper cover 110. The constituent elements such as the disconnecting portion 300 can be accommodated across the inside space of the lower cover 120 and the inside space of the upper cover 110.

[0132] The movable contact 320 of the disconnecting portion 300 is positioned at one side of the lower cover 120, in the illustrated embodiment, the front. The movable contact 320 can be exposed to the outside through an opening portion formed in the lower cover 120. The movable contact 320 can be electrically connected with the external power source or load through the exposed portion.

[0133] The opening portion of the lower cover 120, i.e., the opening portion in which the movable contact 320 is exposed, is combined with a CT magnet portion 500 described later. Detailed description thereof will be made later.

[0134] (2) Explanation of the drive portion 200

[0135] With reference to Figures 1 to 5 , the air circuit breaker 10 of the embodiment includes a driving portion 200.

[0136] The driving portion 200 rotates as the fixed contact 311 and the movable contact 321 of the disconnecting portion 300 are separated, thereby performing a trip mechanism. Thus, the air circuit breaker 10 can be disconnected from the external power supply, and the user can recognize that the operation for disconnecting the power supply has been performed.

[0137] The driving portion 200 is accommodated in the inside of the air circuit breaker 10. Specifically, a part of the driving portion 200 is accommodated in the space inside the cover portion 100. In addition, the remaining part of the driving portion 200 is accommodated in the inside of an unmarked housing provided at one side (the rear side in the illustrated embodiment) of the cover portion 100.

[0138] The driving portion 200 is connected with the disconnecting portion 300. Specifically, the crossbar 220 of the driving portion 200 is configured to rotate together with the rotation of the movable contact 320 of the disconnecting portion 300.

[0139] Thus, if the movable contact 320 of the disconnecting portion 300 is rotationally moved, the driving portion 200 can be rotated together. The driving portion 200 is rotatably accommodated in the inside of the air circuit breaker 10.

[0140] In the illustrated embodiment, the driving portion 200 includes a projection portion 210, a crossbar 220, and a rod 230.

[0141] The projection portion 210 can rotate together with the rotation of the movable contact 320 of the disconnecting portion 300 in the direction away from the fixed contact 310. The projection portion 210 is connected with the crossbar 220 and the rod 230.

[0142] Specifically, the one side end of the projection 210 is restrained by the cross bar 220. An elastic member is provided at the other side end of the projection 210. Thereby, in the state that the fixed contact 311 and the movable contact 321 are in contact, the projection 210 stores the restoring force by pressing the elastic member. The external force for the pressing can be provided by the state that the cross bar 220 is rotated toward the fixed contact 310.

[0143] If the movable contact 321 is separated from the fixed contact 311, the movable contact 320 is rotated toward the direction away from the fixed contact 310. Thereby, the cross bar 220 is also rotated, and the one side end of the projection 210 is released and rotated by the restoring force provided by the elastic member.

[0144] The projection 210 is connected with the lever 230. As the projection 210 is rotated to hit the lever 230, the lever 230 can also be rotated and perform the tripping action.

[0145] The cross bar 220 is connected with the movable contact 320 and is rotated together as the movable contact 320 is rotated. Thereby, the projection 210 restrained by the cross bar 220 is released, so that the tripping action can be performed.

[0146] The cross bar 220 can extend between the plurality of breaking sections 300. In the illustrated embodiment, the movable contacts 320 of the breaking sections 300 are provided in total of three and are arranged in the left-right direction. The cross bar 220 can connect the plurality of movable contacts 320 arranged in the left-right direction by being penetrated.

[0147] The cross bar 220 restrains the projection 210 by being in contact with the one side end of the projection 210. If the cross bar 220 is rotated together with the movable contact 320, the cross bar 220 releases the one side end of the projection 210.

[0148] The lever 230 can be rotated by being hit by the rotated projection 210. A part of the lever 230 can be exposed to the outside of the air circuit breaker 10. If the tripping action is performed through the breaking section 300, the lever 230 is rotated toward the direction set in advance.

[0149] Thereby, the user can easily recognize that the tripping action has been performed. In addition, the user can adjust the air circuit breaker 10 to become the state that the power can be supplied again by performing the rotating operation on the lever 230.

[0150] Since the process that the tripping action is performed through the driving section 200 is a well-known technology, the detailed description thereof is omitted.

[0151] (3) Explanation of the breaking portion 300

[0152] Reference Figures 1 to 5The air circuit breaker 10 according to an embodiment of the present application includes a breaking portion 300.

[0153] The breaking portion 300 includes a fixed contact 310 and a movable contact 320 which are separated from or contacted with each other. If the fixed contact 310 and the movable contact 320 are contacted with each other, the air circuit breaker 10 can be energized with an external power source or load. If the fixed contact 310 and the movable contact 320 are separated from each other, the air circuit breaker 10 is de-energized from the external power source or load.

[0154] The breaking portion 300 is accommodated in the inside of the air circuit breaker 10. Specifically, the breaking portion 300 is rotatably accommodated in the inside space of the cover portion 100.

[0155] The breaking portion 300 can be energized with the outside. In an embodiment, a current can flow from an external power source or load to any one of the fixed contact 310 and the movable contact 320. In addition, the current can flow from the other of the fixed contact 310 and the movable contact 320 to the external power source or load.

[0156] A part of the breaking portion 300 can be exposed to the outside of the air circuit breaker 10. Accordingly, the breaking portion 300 can be electrically connected with the external power source or load through a wire (not shown) or the like.

[0157] The breaking portion 300 can be provided in plural. The plural breaking portions 300 can be arranged apart from each other in one direction. Between the respective breaking portions 300, a partition wall for preventing interference between currents flowing in the respective breaking portions 300 can be provided.

[0158] In the illustrated embodiment, the breaking portion 300 is provided in three. In addition, the three breaking portions 300 are arranged apart from each other in the left-right direction of the air circuit breaker 10. This is because three-phase currents of R phase, S phase, and T phase or U phase, V phase, and W phase flow in the air circuit breaker 10 according to an embodiment of the present application.

[0159] The number of the breaking portion 300 can vary according to the number of phases of a current flowing in the air circuit breaker 10.

[0160] In the illustrated embodiment, the breaking portion 300 includes the fixed contact 310 and the movable contact 320.

[0161] The fixed contact 310 can be contacted with or separated from the movable contact 320. If the movable contact 320 is contacted with the fixed contact 310, the air circuit breaker 10 can be energized with an external power source or load. If the fixed contact 310 and the movable contact 320 are separated from each other, the air circuit breaker 10 is de-energized from the external power source or load.

[0162] As the name implies, the fixed contact 310 is fixedly disposed in the cover portion 100. Thus, the contact and separation of the fixed contact 310 and the movable contact 320 are achieved by the rotation of the movable contact 320.

[0163] In the illustrated embodiment, the fixed contact 310 is accommodated in the internal space of the upper cover 110.

[0164] A portion of the fixed contact 310 can be exposed to the outside of the air circuit breaker 10. Through the exposed portion, the fixed contact 310 can be electrically connectable with an external power source or load.

[0165] In the illustrated embodiment, the fixed contact 310 can be exposed to the outside through an opening portion formed in the front side of the upper cover 110.

[0166] The fixed contact 310 can be formed of a material having electrical conductivity. In an embodiment, the fixed contact 310 can be formed of copper (Cu) or iron (Fe) and an alloy material including the same.

[0167] In the illustrated embodiment, the fixed contact 310 includes a fixed contact point 311.

[0168] The fixed contact point 311 can be in contact with or separated from the movable contact point 321. The fixed contact point 311 is located at a side of the fixed contact 310 facing the movable contact 320, which is the rear side in the illustrated embodiment.

[0169] The fixed contact point 311 is electrically connected with the fixed contact 310. In the illustrated embodiment, the fixed contact point 311 is located at the rear side of the fixed contact 310. In an embodiment, the fixed contact point 311 can be formed in one body with the fixed contact 310.

[0170] If the fixed contact point 311 and the movable contact point 321 are in contact, the air circuit breaker 10 can be electrically connected with an external power source or load. In addition, if the fixed contact point 311 is separated from the movable contact point 321, the electrical connection of the air circuit breaker 10 with the external power source or load is broken.

[0171] The movable contact 320 can be in contact with or separated from the fixed contact 310. As described before, the air circuit breaker 10 can be electrically connected with or disconnected from an external power source or load by the contact and separation of the movable contact 320 and the fixed contact 310.

[0172] The movable contact 320 is rotatably disposed in the internal space of the cover portion 100. The movable contact 320 can be rotated in a direction toward the fixed contact 310 and a direction away from the fixed contact 310.

[0173] In the illustrated embodiment, the movable contact 320 is housed in the interior space of the upper cover 110 and the lower cover 120. As described above, the interior space of the upper cover 110 and the interior space of the lower cover 120 can be in communication with each other.

[0174] A portion of the movable contact 320 can be exposed to the outside of the air circuit breaker 10. Through the exposed portion, the movable contact 320 can be electrically connected with an external power source or load.

[0175] In the illustrated embodiment, the movable contact 320 is exposed to the outside through an opening portion formed in the front side of the lower cover 120.

[0176] The opening portion can be covered by the CT magnet portion 500, which will be described later. Thereby, the opening portion can be closed except for the portion of the movable contact 320 that is electrically connected with the external power source or load.

[0177] The movable contact 320 can be formed of a material having electrical conductivity. In an embodiment, the movable contact 320 can be formed of copper or iron, and an alloy material including the same.

[0178] The movable contact 320 is connected with the driving portion 200. Specifically, the movable contact 320 is connected with the cross bar 220 of the driving portion 200. In an embodiment, the cross bar 220 can be penetratingly coupled to the movable contact 320.

[0179] If the movable contact 320 rotates, the cross bar 220 can also rotate. Thereby, as described above, the tripping action can be performed by the operation of the driving portion 200.

[0180] In the illustrated embodiment, the movable contact 320 includes a movable contact point 321 and a rotating shaft 322.

[0181] The movable contact point 321 can be in contact with or separated from the fixed contact point 311. The movable contact point 321 is located at the side of the movable contact 320 facing the fixed contact 310, which is the front side in the illustrated embodiment.

[0182] The movable contact point 321 can rotate together with the movable contact 320. If the movable contact 320 rotates toward the fixed contact 310, the movable contact point 321 can also rotate toward the fixed contact 311 and be in contact with the fixed contact 311.

[0183] In addition, if the movable contact 320 rotates in a direction away from the fixed contact 310, the movable contact point 321 can also be separated from the fixed contact 311.

[0184] The movable contact 321 is in contact with the movable contact 320. In the illustrated embodiment, the movable contact 321 is positioned on the front side of the movable contact 320. In one embodiment, the movable contact 321 can be formed integrally with the movable contact 320.

[0185] As described above, the air circuit breaker 10 is in contact or disconnected with an external power source or load by contact and separation of the movable contact 321 and the fixed contact 311.

[0186] In a state where the fixed contact 311 and the movable contact 321 are in contact with each other and thus in contact, if the fixed contact 311 and the movable contact 321 are separated, an arc is generated. The air circuit breaker 10 of the embodiment of the present application includes various configurations for efficiently forming a path of the generated arc. Explanation thereof will be made later.

[0187] The rotation shaft 322 is a portion of the movable contact 320 that is rotatably coupled to the cover portion 100. The movable contact 320 can be rotated about the rotation shaft 322 in a direction toward the fixed contact 310 or a direction away from the fixed contact 310.

[0188] The rotation shaft 322 is positioned on the other side of the movable contact 320 opposite the fixed contact 310, and in the illustrated embodiment, on the rear side.

[0189] 3. Explanation of the cover magnet portion 400 according to the embodiment of the present application

[0190] Referring to Figures 6 to 7 The air circuit breaker 10 of the embodiment of the present application includes a cover magnet portion 400.

[0191] The cover magnet portion 400 forms a magnetic field. Through the magnetic field, an arc path A.P. for an arc generated in the arc extinguishing portions 600, 700 to flow can be formed.

[0192] The cover magnet portion 400 can be provided in any form capable of forming a magnetic field. In one embodiment, the cover magnet portion 400 can be a permanent magnet or an electromagnet, etc.

[0193] The cover magnet portion 400 is coupled to the upper cover 110 of the air circuit breaker 10. The cover magnet portion 400 is positioned between and outside the plurality of arc extinguishing portions 600, 700, respectively.

[0194] In the illustrated embodiment, the plurality of arc extinguishing portions 600, 700 are positioned adjacent to the plurality of fixed contacts 311, respectively.

[0195] In one embodiment, the cover magnet portion 400 can be configured to be more adjacent to the arc extinguishing portions 600, 700 than the plurality of fixed contacts 311. That is, the cover magnet portion 400 can be positioned between the fixed contacts 311 and the arc extinguishing portions 600, 700 in the up-and-down direction.

[0196] In the illustrated embodiment, one side of the cover magnet portion 400 is coupled to the second upper cover 112, and the other side extends toward the first upper cover 111. That is, the cover magnet portion 400 extends in the front-rear direction.

[0197] In the illustrated embodiment, the first upper cover 111 can be recessed to form a receiving groove for receiving the cover magnet portion 400.

[0198] Alternatively, the cover magnet portion 400 can be coupled to the first upper cover 111 and extend toward the second upper cover 112. That is, the cover magnet portion 400 can be coupled to any one of the first upper cover 111 and the second upper cover 112.

[0199] In the illustrated embodiment, the second upper cover 112 can be recessed to form a receiving groove for receiving the cover magnet portion 400.

[0200] That is, the first upper cover 111 and the second upper cover 112 can be recessed to form receiving grooves for receiving a portion and the remaining portion of the cover magnet portion 400, respectively.

[0201] Thus, if the cover magnet portion 400 is coupled to the upper cover 110, the cover magnet portion 400 is not exposed to the outside. Therefore, the cover magnet portion 400 is not damaged by an electric arc generated.

[0202] The cover magnet portion 400 can be provided in plural. The plural cover magnet portions 400 can be arranged apart from each other. In the illustrated embodiment, four cover magnet portions 400 are provided.

[0203] Each of the cover magnet portions 400 can be arranged outside each of the arc extinguishing portions 600, 700 arranged side by side and between the arc extinguishing portions 600, 700.

[0204] In the illustrated embodiment, the cover magnet portion 400 includes a first cover magnet 410, a second cover magnet 420, a third cover magnet 430, and a fourth cover magnet 440.

[0205] The first cover magnet 410 is located outside the plurality of arc extinguishing portions 600, 700. In the illustrated embodiment, the plurality of arc extinguishing portions 600, 700 are arranged side by side in the left-right direction.

[0206] The first cover magnet 410 is located outside (i.e., left side) of the leftmost arc extinguishing portion 600, 700 among the plurality of arc extinguishing portions 600, 700. The first cover magnet 410 is configured to cover a portion of the outside (i.e., left side) of the leftmost arc extinguishing portion 600, 700 among the plurality of arc extinguishing portions 600, 700.

[0207] The first cover magnet 410 can form a main magnetic field M.M.F. with the second cover magnet 420. In addition, the first cover magnet 410 can form a secondary magnetic field S.M.F. by itself.

[0208] The first cover magnet 410 includes a first face 411 and a second face 412.

[0209] The first face 411 is defined by one side face of the first cover magnet 410, which faces the grid cover 630, 730 of the arc extinguishing part 600, 700. In the illustrated embodiment, the first face 411 forms an upper side face of the first cover magnet 410.

[0210] The second face 412 is defined by the other side face of the first cover magnet 410, which is opposite to the grid cover 630, 730 of the arc extinguishing part 600, 700. In the illustrated embodiment, the second face 412 forms a lower side face of the first cover magnet 410.

[0211] The first face 411 and the second face 412 are configured to be opposite to each other. In other words, the first face 411 and the second face 412 are one side face and the other side face of the first cover magnet 410, which are opposite to each other.

[0212] The first face 411 can be magnetized as an S pole. In addition, the second face 412 can be magnetized as an N pole.

[0213] That is, the first face 411 and the second face 412 are magnetized as opposite polarities to each other. Accordingly, a secondary magnetic field S.M.F. can be formed between the first face 411 and the second face 412.

[0214] The second cover magnet 420 is located at any one position among the plurality of arc extinguishing parts 600, 700. In the illustrated embodiment, the second cover magnet 420 is located between the leftmost arc extinguishing part 600, 700 and the central arc extinguishing part 600, 700 among the plurality of arc extinguishing parts 600, 700.

[0215] The second cover magnet 420 is configured to cover a portion of an inner side (i.e., right side) of the leftmost arc extinguishing part 600, 700 and a portion of an inner side (i.e., left side) of the central arc extinguishing part 600, 700 among the plurality of arc extinguishing parts 600, 700.

[0216] The second cover magnet 420 can form a main magnetic field M.M.F. with the first cover magnet 410 and the third cover magnet 430. In addition, the second cover magnet 420 can form a secondary magnetic field S.M.F. by itself.

[0217] The second cover magnet 420 includes a first face 421 and a second face 422.

[0218] The first face 421 is defined by one side face of the second cover magnet 420 among the faces thereof facing the grid cover 630, 730 of the arc extinguishing portion 600, 700. In the illustrated embodiment, the first face 421 forms the upper side face of the second cover magnet 420.

[0219] The second face 422 is defined by the other side face of the second cover magnet 420 among the faces thereof opposite to the grid cover 630, 730 of the arc extinguishing portion 600, 700. In the illustrated embodiment, the second face 422 forms the lower side face of the second cover magnet 420.

[0220] The first face 421 and the second face 422 are configured to face each other. In other words, the first face 421 and the second face 422 are one side face and the other side face of the second cover magnet 420 facing each other.

[0221] The first face 421 can be magnetized to be an S pole. In addition, the second face 422 can be magnetized to be an N pole. That is, the first face 421 and the second face 422 are magnetized to be polarities opposite to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 421 and the second face 422.

[0222] The third cover magnet 430 is located at another position among the plurality of arc extinguishing portions 600, 700. Specifically, the third cover magnet 430 is located between the arc extinguishing portion 600, 700 located at the center among the plurality of arc extinguishing portions 600, 700 and the arc extinguishing portion 600, 700 located at the rightmost side.

[0223] The third cover magnet 430 is configured to cover a portion of the other inner side (i.e., the right side) of the arc extinguishing portion 600, 700 located at the center among the plurality of arc extinguishing portions 600, 700 and a portion of the inner side (i.e., the left side) of the arc extinguishing portion 600, 700 located at the leftmost side.

[0224] The third cover magnet 430 can form a main magnetic field M.M.F. with the second cover magnet 410 and the fourth cover magnet 440. In addition, the third cover magnet 430 itself can form a secondary magnetic field S.M.F.

[0225] The third cover magnet 430 includes a first face 431 and a second face 432.

[0226] The first face 431 is defined by one side face of the third cover magnet 430 among the faces thereof facing the grid cover 630, 730 of the arc extinguishing portion 600, 700. In the illustrated embodiment, the first face 431 forms the upper side face of the third cover magnet 430.

[0227] The second face 432 is defined by the other side face of the third cover magnet 430 among the faces thereof opposite to the grid cover 630, 730 of the arc extinguishing portion 600, 700. In the illustrated embodiment, the second face 432 forms the lower side face of the third cover magnet 430.

[0228] The first face 431 and the second face 432 are configured to be opposite to each other. In other words, the first face 431 and the second face 432 are one side face and the other side face of the third cover magnet 430 opposite to each other.

[0229] The first face 431 can be magnetized as an S pole. In addition, the second face 432 can be magnetized as an N pole. That is, the first face 431 and the second face 432 are magnetized as opposite polarities to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 431 and the second face 432.

[0230] The fourth cover magnet 440 is located outside (i.e., right side) of the rightmost arc extinguishing part 600, 700 among the plurality of arc extinguishing parts 600, 700. The fourth cover magnet 440 is configured to cover a portion of the outside (i.e., right side) of the rightmost arc extinguishing part 600, 700 among the plurality of arc extinguishing parts 600, 700.

[0231] The fourth cover magnet 440 can form a main magnetic field M.M.F. with the third cover magnet 430. In addition, the fourth cover magnet 440 can form a secondary magnetic field S.M.F. by itself.

[0232] The fourth cover magnet 440 includes a first face 441 and a second face 442.

[0233] The first face 441 is defined by one side face of the fourth cover magnet 440 facing the grid cover 630, 730 of the arc extinguishing part 600, 700. In the illustrated embodiment, the first face 441 forms an upper side face of the fourth cover magnet 440.

[0234] The second face 442 is defined by the other side face of the fourth cover magnet 440 opposite to the grid cover 630, 730 of the arc extinguishing part 600, 700. In the illustrated embodiment, the second face 442 forms a lower side face of the fourth cover magnet 440.

[0235] The first face 441 and the second face 442 are configured to be opposite to each other. In other words, the first face 441 and the second face 442 are one side face and the other side face of the fourth cover magnet 440 opposite to each other.

[0236] The first face 441 can be magnetized as an S pole. In addition, the second face 442 can be magnetized as an N pole. That is, the first face 441 and the second face 442 are magnetized as opposite polarities to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 441 and the second face 442.

[0237] The thickness of the second cover magnet 420 can be thicker than the thickness of the first cover magnet 410 and the fourth cover magnet 440. As described above, since the second cover magnet 420 can form the main magnetic field M.M.F with the first cover magnet 410 and the third cover magnet 430, this is to ensure sufficient magnetic force.

[0238] Likewise, the thickness of the third cover magnet 430 can also be thicker than the thickness of the first cover magnet 410 and the fourth cover magnet 440. As described above, since the third cover magnet 430 can form the main magnetic field M.M.F with the second cover magnet 420 and the fourth cover magnet 440, this is to ensure sufficient magnetic force.

[0239] In an embodiment, the thickness of the third cover magnet 430 and the thickness of the second cover magnet 420 can be the same. In addition, the thickness of the first cover magnet 410 and the thickness of the fourth cover magnet 440 can be the same.

[0240] In the present embodiment, the cover magnet portion 400 is directly combined with the upper cover 110. Thereby, the assembly convenience of the air circuit breaker 10 can be improved.

[0241] In addition, with the cover magnet portion 400 of the present embodiment provided, the generated arc can effectively flow toward the arc extinguishing portion 600, 700. This is achieved by the main magnetic field M.M.F and the secondary magnetic field S.M.F formed by the cover magnet portion 400. For this, a detailed explanation will be given later.

[0242] 4. Explanation of the CT (Current Transformer) magnet portion 500 according to the embodiment of the present application Figure 1

[0243] With reference to Figure 8 , Figure 9 and 5. Explanation of the arc extinguishing portion 600 according to the embodiment of the present application , the air circuit breaker 10 of the present embodiment includes a CT magnet portion 500.

[0244] The CT magnet portion 500 can be detachably combined with the lower cover 120 to cover the opening portion of the lower cover 120 for exposing a portion of the movable contact 320.

[0245] In addition, the CT magnet 530 is included in the inside of the CT magnet portion 500, thereby forming a magnetic field for forming an arc path A.P.

[0246] The CT magnet portion 500 can be provided with a plurality of. In the illustrated embodiment, the movable contact 320 and the opening portion of the lower cover 120 can be provided with three. Thereby, the CT magnet portion 500 can also be provided with three.

[0247] A space is formed inside the CT magnet portion 500. The CT magnet 530 can be accommodated in the space. When the current flowing in the air circuit breaker 10 is alternating current, various components for a current transformer can be installed in the space.

[0248] Hereinafter, a case where a direct current flows in the air circuit breaker 10 according to the embodiment of the present application will be described as a premise.

[0249] In the illustrated embodiment, the CT magnet portion 500 includes a housing 510, a space portion 520, a CT magnet 530, and a cover portion 540.

[0250] The housing 510 forms the appearance of the CT magnet portion 500. The housing 510 is detachably coupled to the lower cover 120 to cover the opening portion of the lower cover 120.

[0251] The space portion 520 is formed inside the housing 510. The CT magnet 530 can be accommodated in the space portion 520. As described above, in the embodiment where an alternating current flows in the air circuit breaker 10, various components for a current transformer can be installed in the space portion 520.

[0252] On the contrary, in the embodiment where a direct current flows in the air circuit breaker 10, components for a current transformer are not required. Thus, it can be understood that the embodiment where the CT magnet 530 is accommodated in the space portion 520 is a case where a direct current flows in the air circuit breaker 10.

[0253] An opening portion is formed inside the housing 510. The opening portion communicates with the opening portion of the lower cover 120. The movable contact 320 can be exposed to the outside through the opening portion.

[0254] The space portion 520 is a space formed inside the housing 510. The space portion 520 can be defined as a space surrounded by the outer surface and the inner surface of the housing 510.

[0255] The CT magnet 530 is accommodated in the space portion 520. As described above, the embodiment is a case where an alternating current flows in the air circuit breaker 10.

[0256] The space portion 520 includes an open portion which is open. The open portion is formed in the space portion 520 at a side opposite to the cover portion 100, i.e., the front side in the illustrated embodiment. The open portion can be closed by the cover portion 540.

[0257] In the illustrated embodiment, the space portion 520 is defined by a space which surrounds the opening portion formed inside the housing 510 and is surrounded by the outer surface of the housing 510.

[0258] A fastening member (not shown) for coupling the case 510 to the cover 100 can be accommodated in the space portion 520. In addition, a fastening member for coupling the cover 540 to the case 510 can be accommodated in the space portion 520.

[0259] The CT magnet 530 forms a magnetic field. By the magnetic field, an arc path A.P. for an arc generated in the arc extinguishing portion 600, 700 to flow can be formed.

[0260] Specifically, the CT magnet 530 forms a magnetic field in a direction from the arc extinguishing portion 600, 700 toward the CT magnet 530 or in a direction from the CT magnet 530 toward the arc extinguishing portion 600, 700.

[0261] Thus, the generated arc is subjected to an electromagnetic force in a direction toward both sides of the grid 720 provided in the arc extinguishing portion 600, 700. Therefore, the arc path A.P. is formed toward a peak formed in both sides of the grid 720, so that the arc can effectively flow toward the arc extinguishing portion 600, 700.

[0262] The CT magnet 530 can be provided in any form capable of forming a magnetic field. In an embodiment, the CT magnet 530 can be a permanent magnet or an electromagnet, etc.

[0263] The CT magnet 530 is coupled to the case 510. Specifically, the CT magnet 530 is accommodated in a space portion 520 formed in the inside of the case 510. The CT magnet 530 is coupled to a side of the case 510 facing the cover 100, which is a rear side in the illustrated embodiment.

[0264] In an embodiment, the CT magnet 530 can also be coupled to a side surrounding the opening portion of the case 510. In the embodiment, the CT magnet 530 can be more stably coupled to the case 510.

[0265] In the illustrated embodiment, the CT magnet 530 is positioned on the upper side of the opening portion of the case 510. In other words, the CT magnet 530 is positioned between the opening portion of the case 510 and the arc extinguishing portion 600, 700.

[0266] Alternatively, the CT magnet 530 can be positioned on the lower side of the opening portion of the case 510. That is, the CT magnet 530 can be configured such that the opening portion of the case 510 is positioned between the CT magnet 530 and the arc extinguishing portion 600, 700. In this case, the distance between the CT magnet 530 and the arc extinguishing portion 600, 700 increases, so it is preferable to increase the magnetic force of the CT magnet 530.

[0267] In order to prevent the coupled CT magnet 530 from being arbitrarily separated and shaken, a fixing member (not shown) such as a screw or a frame can be provided.

[0268] The CT magnet 530 includes a first face 531 and a second face 532.

[0269] The first face 531 can be defined by a side of the faces of the CT magnet 530 facing the arc extinguishing portion 600, 700. In the illustrated embodiment, the arc extinguishing portion 600, 700 is located on the upper side of the CT magnet 530.

[0270] Accordingly, the first face 531 can be defined by the upper side of the CT magnet 530.

[0271] The second face 532 can be defined by a side of the faces of the CT magnet 530 opposite the arc extinguishing portion 600, 700. In other words, the second face 532 can be defined by the lower side of the CT magnet 530.

[0272] The first face 531 and the second face 532 are configured to oppose each other. In other words, the first face 531 and the second face 532 are a side and another side of the CT magnet 530 opposing each other.

[0273] The first face 531 can be magnetized to either of N-pole and S-pole. In addition, the second face 532 can be magnetized to the other of N-pole and S-pole. That is, the first face 531 and the second face 532 are magnetized to opposite polarities to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 531 and the second face 532.

[0274] As will be described later, the arc extinguishing portion 600 of an embodiment of the present application can be provided with an arc extinguishing magnet 634. In the embodiment, a primary magnetic field M.M.F. can be formed between the first face 531 and a first face 633a of the arc extinguishing magnet 634.

[0275] As described above, the embodiment in which the direct current flows in the air circuit breaker 10 does not require a component for current conversion.

[0276] Accordingly, in the present embodiment, in the case where the direct current flows in the air circuit breaker 10, the CT magnet 530 is provided in the CT magnet portion 500. The CT magnet 530 itself forms the secondary magnetic field S.M.F., and together with the arc extinguishing magnet 634 of the arc extinguishing portion 600, forms the primary magnetic field M.M.F.

[0277] Thereby, the generated arc can be effectively extinguished in the process through the arc extinguishing portion 600. Details of this will be described later.

[0278] Figures 10 to 18

[0279] With reference to 6. Explanation of the arc extinguishing portion 700 according to another embodiment of the present application , the air circuit breaker 10 of an embodiment of the present application includes an arc extinguishing portion 600.

[0280] The arc extinguishing portion 600 is configured to extinguish the arc generated due to the separation of the fixed contact 311 and the movable contact 321. The generated arc can be extinguished and cooled while passing through the arc extinguishing portion 600, and then discharged to the outside of the air circuit breaker 10.

[0281] The arc extinguishing portion 600 is combined with the cover portion 100. The side of the arc extinguishing portion 600 for discharging the arc can be exposed to the outside of the cover portion 100. In the illustrated embodiment, the upper side of the arc extinguishing portion 600 is exposed to the outside of the cover portion 100.

[0282] A part of the arc extinguishing portion 600 is accommodated in the cover portion 100. The remaining part of the arc extinguishing portion 600 except for the part exposed to the outside can be accommodated in the internal space of the cover portion 100. In the illustrated embodiment, a part of the arc extinguishing portion 600 can be accommodated in the upper side of the upper cover 110.

[0283] The configuration can vary depending on the positions of the fixed contact 311 and the movable contact 312. That is, the arc extinguishing portion 600 can be located adjacent to the fixed contact 311 and the movable contact 312. Thereby, the arc extending along the movable contact 312 rotating in the direction away from the fixed contact 311 can easily enter the arc extinguishing portion 600.

[0284] The arc extinguishing portion 600 can be provided in plural. The plural arc extinguishing portions 600 can be physically and electrically separated from each other. In the illustrated embodiment, three arc extinguishing portions 600 are provided. This is because, as described above, three-phase currents flow in the air circuit breaker 10 of the embodiment of the present application.

[0285] That is, each of the arc extinguishing portions 600 is located adjacent to each of the fixed contacts 311 and the movable contacts 321. In the illustrated embodiment, each of the arc extinguishing portions 600 is located adjacent to the upper side of each of the fixed contacts 311 and the movable contacts 321.

[0286] It can be understood that each of the arc extinguishing portions 600 is configured to extinguish the arc generated at the time of the disconnection of each of the phase currents flowing in each of the disconnecting portions 300.

[0287] The arc extinguishing portions 600 can be arranged adjacent to each other. In the illustrated embodiment, the three arc extinguishing portions 600 are arranged side by side in the left-right direction of the air circuit breaker 10.

[0288] In the present embodiment, the arc extinguishing portion 600 includes an arc extinguishing magnet 634. The arc extinguishing magnet 634 forms an arc path A.P. for the generated arc to flow effectively toward the arc extinguishing portion 600 by forming a main magnetic field M.M.F and a secondary magnetic field S.M.F. Details thereof will be described later.

[0289] In the illustrated embodiment, the arc extinguishing portion 600 includes a support plate 610, a grid 620, a grid cover 630, an arc guide 640, and an arc runner 650.

[0290] The support plate 610 forms both sides of the arc extinguishing portion 600, in the illustrated embodiment, the right side and the left side. The support plate 610 is combined with and supports each of the constituent elements of the arc extinguishing portion 600.

[0291] Specifically, the support plate 610 is combined with the grid 620, the grid cover 630, the arc guide 640, and the arc runner 650.

[0292] The support plate 610 is provided in plural. The plural support plates 610 can be arranged to be spaced apart from and opposite to each other. In the illustrated embodiment, the support plate 610 is provided in two and forms the right side and the left side of the arc extinguishing portion 600, respectively.

[0293] The support plate 610 can be formed of an insulating material. This is to prevent the generated arc from flowing toward the support plate 610.

[0294] The support plate 610 can be formed of a heat-resistant material. This is to prevent damage or deformation due to the generated arc.

[0295] Plural through-holes are formed in the support plate 610. The grid 620 and the arc runner 650 can be inserted and combined into a part of the through-holes. In addition, another part of the through-holes can be through-combined with fastening members for fastening the grid cover 630 and the arc guide 640 to the support plate 610.

[0296] In the illustrated embodiment, the support plate 610 is formed in a plate shape having plural corners formed at the apex. The support plate 610 can be provided in any form that forms both sides of the arc extinguishing portion 600 and is capable of supporting each of the constituent elements of the arc extinguishing portion 600.

[0297] The support plate 610 is combined with the grid 620. Specifically, the insertion protrusions provided at both sides, in the illustrated embodiment, the right end portion and the left end portion, of the grid 620 are inserted and combined into a part of the through-holes of the support plate 610.

[0298] The support plate 610 is combined with the grid cover 630. Specifically, the grid cover 630 is combined on the upper side of the support plate 610. The combination can be achieved by insertion combination of the support plate 610 and the grid cover 630 or by an additional fastening member.

[0299] The support plate 610 is combined with the arc guide 640. Specifically, the arc guide 640 is combined on the lower side of the support plate 610, that is, the side opposite to the grid cover 630. The combination can be achieved by an additional fastening member.

[0300] The support plate 610 is combined with the arc flow path 650. Specifically, the arc flow path 650 is combined on the rear side of the support plate 610, that is, on the side opposite to the fixed contact 311. The combination can be achieved by an additional fastening member.

[0301] The grid 620 guides the arc generated due to the separation of the fixed contact 311 and the movable contact 321 toward the arc extinguishing portion 600.

[0302] The guidance can be achieved by the magnetic force generated by the grid 620. In addition, the guidance can be achieved by the arc extinguishing magnet 634 provided to the arc extinguishing portion 600.

[0303] The grid 620 can be formed of a material having magnetism. This is to apply an attractive force to the arc that is the flow of electrons.

[0304] The grid 620 can be provided in plural. The plural grids 620 can be spaced apart from each other and stacked. In the illustrated embodiment, the grid 620 is provided in nine and stacked in the front-rear direction.

[0305] The number of the grid 620 can be changed. Specifically, the number of the grid 620 can vary depending on the size, performance, or rated capacity of the air circuit breaker 10 having the arc extinguishing portion 600, and the like.

[0306] The arc flowing in is divided into smaller flows by the spaces formed by the plural grids 620 being spaced apart from each other. Therefore, the pressure of the arc can be increased, and the moving speed of the arc and the arc extinguishing speed can be improved.

[0307] The arc flow path 650 is located adjacent to the grid 620 farthest from the fixed contact 311 among the plural grids 620, that is, the grid 620 on the rear side in the illustrated embodiment.

[0308] The end portion of the grid 620 in the width direction, that is, the left-right direction in the illustrated embodiment, can be formed protruding toward the fixed contact 311, that is, the lower side. That is, the grid 620 is formed in a peak shape with the end portion in the left-right direction facing the lower side.

[0309] Thus, the generated arc can effectively travel toward the end portion of the grid 620 in the left-right direction, and thus easily flow toward the arc extinguishing portion 600.

[0310] The arc guide 640 is located outside the end portion of the grid 620 in the left-right direction, that is, on the lower side in the illustrated embodiment.

[0311] The grid 620 is combined with the support plate 610. Specifically, at the edges of the grid 620 in the width direction, in the illustrated embodiment, the left and right directions, a plurality of combination protrusions are formed, and a plurality of the combination protrusions are formed in the direction in which the grid 620 extends, in the illustrated embodiment, the up and down directions. The combination protrusions of the grid 620 are inserted into the through holes formed in the support plate 610.

[0312] The side of the grid 620 facing the grid cover 630, in the illustrated embodiment, the upper side end portion, can be positioned adjacent to the grid cover 630. The electric arc flowing along the grid 620 can be discharged to the outside through the grid cover 630.

[0313] The grid cover 630 forms the upper side of the arc extinguishing portion 600. The grid cover 630 is configured to cover the upper side end portion of the grid 620. The electric arc that has passed through the spaces formed by the plurality of grids 620 spaced apart from each other can be discharged to the outside of the air circuit breaker 10 via the grid cover 630.

[0314] The grid cover 630 is combined with the support plate 610. At the edges of the grid cover 630 in the width direction, in the illustrated embodiment, the left and right directions, protrusions that are inserted into the through holes of the support plate 610 can be formed. In addition, the grid cover 630 and the support plate 610 can be combined using an additional fastening member.

[0315] The grid cover 630 is formed so as to extend in one direction, in the illustrated embodiment, the front and back directions. It can be understood that the direction is the same as the stacking direction of the plurality of grids 620.

[0316] The length of the grid cover 630 in the other direction, in the illustrated embodiment, the width direction, can be determined in accordance with the length in the width direction of the plurality of grids 620.

[0317] In the illustrated embodiment, the grid cover 630 includes a cover main body 631, an upper frame 632, a mesh portion 633, an arc extinguishing magnet 634, a magnet cover 635, and a barrier plate 636.

[0318] The cover main body 631 forms the appearance of the grid cover 630. The cover main body 631 is combined with the support plate 610. In addition, the upper frame 632 is combined with the cover main body 631.

[0319] A prescribed space is formed inside the cover main body 631. The space can be covered by the upper frame 632. The mesh portion 633, the arc extinguishing magnet 634, the magnet cover 635, and the barrier plate 636 are accommodated in the space. Thus, the space can be referred to as an "accommodation space".

[0320] The receiving space is connected to the space formed by the grille 620. As a result, the receiving space is connected to the interior space of the cover 100. Thus, the generated electric arc can flow into the receiving space of the cover body 631 through the space formed by the grille 620.

[0321] In the illustrated embodiment, the lower side of the cover body 631 facing the grille 620 can contact the upper end of the grille 620. In one embodiment, the cover body 631 can support the upper end of the grille 620.

[0322] The cover body 631 can be formed of an insulating material. This is to prevent the magnetic field of the path AP used to form the electric arc from being distorted.

[0323] The cover body 631 may be formed of a heat-resistant material. This is to prevent the cover body 631 from being damaged or deformed by the generated electric arc.

[0324] In the illustrated embodiment, the length of the cover body 631 in the front-to-back direction is greater than its length in the left-to-right direction. The shape of the cover body 631 can vary depending on the shape of the support plate 610 and the shape and number of the grilles 620.

[0325] On the side of the cover body 631 opposite to the grille 620, in the illustrated embodiment, an upper frame 632 is attached to the upper side.

[0326] The upper frame 632 is joined to the upper side of the cover body 631. The upper frame 632 is configured to cover the receiving space formed in the cover body 631 and the mesh portion 633, arc-extinguishing magnet 634, magnet cover 635 and barrier plate 636 housed in the receiving space.

[0327] In the illustrated embodiment, the length of the upper frame 632 in the front-to-back direction is greater than its length in the left-to-right direction. The upper frame 632 can be formed in any shape that is stably attached to the upper side of the cover body 631 and is capable of covering the receiving space and the constituent elements contained in the receiving space.

[0328] A plurality of through holes are formed in the upper frame 632. Through these through holes, electric arcs that have passed through and been extinguished between the grids 620 can be discharged. In the illustrated embodiment, three through holes are arranged in the left-right direction and three rows in the front-back direction, thus forming a total of nine through holes. The number of through holes can be varied.

[0329] The through holes are spaced apart from each other. A rib is formed between the through holes. The rib can pressurize the mesh portion 633, the arc-extinguishing magnet 634, the magnet cover 635, and the barrier plate 636, which are housed in the space of the cover body 631, from the top.

[0330] Thus, even if an arc occurs, the grid portion 633, the arc extinguishing magnet 634, the magnet cover 635, and the barrier plate 636 do not come off the accommodation space of the cover main body 631.

[0331] The upper frame 632 can be fixedly coupled to the upper side of the cover main body 631. In the illustrated embodiment, the upper frame 632 is fixedly coupled to the upper side of the cover main body 631 by a fastening member.

[0332] The grid portion 633, the arc extinguishing magnet 634, the magnet cover 635, and the barrier plate 636 are positioned between the upper frame 632 and the cover main body 631, i.e., on the lower side of the upper frame 632 in the accommodation space of the cover main body 631.

[0333] In other words, in the accommodation space of the cover main body 631, the grid portion 633, the arc extinguishing magnet 634, the magnet cover 635, and the barrier plate 636 are stacked from the upper side toward the lower side.

[0334] The grid portion 633 functions to filter impurities remaining in an arc that is extinguished in the process of passing through the space formed between the grids 620. The extinguished arc can pass through the grid portion 633 and be discharged to the outside after the remaining impurities are removed.

[0335] That is, the grid portion 633 functions as a kind of filter.

[0336] The grid portion 633 includes a plurality of through-holes. Preferably, the size, i.e., the diameter, of the through-holes is smaller than the diameter of the impurity particles remaining in the arc. In addition, preferably, the diameter of the through-holes is formed to be sufficiently large so that the gas included in the arc can pass through.

[0337] The grid portion 633 can be provided in plural. The plural grid portions 633 can be stacked in the up-and-down direction. Thus, the impurities remaining in the arc that passes through the grid portion 633 can be effectively removed.

[0338] The grid portion 633 is accommodated in the accommodation space formed in the inside of the cover main body 631. The shape of the grid portion 633 can be determined according to the shape of the accommodation space.

[0339] The grid portion 633 is positioned on the lower side of the upper frame 632. The plurality of through-holes formed in the grid portion 633 communicate with the plurality of through-holes formed in the upper frame 632. Thus, the arc that has passed through the grid portion 633 can be discharged to the outside through the upper frame 632.

[0340] The plurality of through-holes formed in the grid portion 633 communicate with the space formed by the grids 620. As a result, the plurality of through-holes formed in the grid portion 633 communicate with the inside space of the cover portion 100.

[0341] The arc extinguishing magnet 634, the magnet cover 635, and the barrier plate 636 are located on the lower side of the grid portion 633.

[0342] The arc extinguishing magnet 634 forms a magnetic field that forms an electromagnetic force for flowing the generated arc toward the arc extinguishing portion 600. The arc extinguishing magnet 634 is housed inside the housing space of the cover main body 631.

[0343] The arc extinguishing magnet 634 is located on the lower side of the grid portion 633. In addition, the arc extinguishing magnet 634 is located on the upper side of the barrier plate 636. In an embodiment, the arc extinguishing magnet 634 can be disposed on the barrier plate 636.

[0344] The arc extinguishing magnet 634 can be provided in any form capable of forming a magnetic field. In an embodiment, the arc extinguishing magnet 634 can be a permanent magnet or an electromagnet.

[0345] The arc extinguishing magnet 634 can be formed in a prescribed size. Specifically, as described later, a plurality of through holes 636a can be formed in the barrier plate 636. Preferably, the arc extinguishing magnet 634 is formed in a size that does not cover the through holes 636a formed in the barrier plate 636.

[0346] In the illustrated embodiment, the arc extinguishing magnet 634 is formed in a rectangular shape. The arc extinguishing magnet 634 is formed so that its length is half or less of the length of the barrier plate 636 in the front-rear direction. In addition, the arc extinguishing magnet 634 is formed so as to be smaller than the length of the barrier plate 636 in the width direction.

[0347] The arc extinguishing magnet 634 can be formed in any size and shape that does not obstruct the through holes 636a. For example, the arc extinguishing magnet 634 can have a width that is the same as the length of the barrier plate 636 in the width direction.

[0348] In the illustrated embodiment, the arc extinguishing magnet 634 is located on the front side of the housing space of the cover main body 631. In other words, the arc extinguishing magnet 634 is located on the opposite side of the position where the plurality of through holes 636a are formed in the housing space of the cover main body 631.

[0349] The arc extinguishing magnet 634 can be disposed at any position that does not obstruct the plurality of through holes 636a.

[0350] The arc extinguishing magnet 634 is supported by the magnet cover 635. Specifically, the arc extinguishing magnet 634 is inserted into the second opening portion 635b formed in the magnet cover 635.

[0351] Thus, the up-down direction wobble of the arc extinguishing magnet 634 is restricted by the upper frame 632, the grid portion 633, and the barrier plate 636. In addition, the front-rear direction and the left-right direction wobbles of the arc extinguishing magnet 634 are restricted by the magnet cover 635.

[0352] The arc extinguishing magnet 634 includes a first face 634a and a second face 634b.

[0353] The first face 634a forms a side of the arc extinguishing magnet 634 facing the grid portion 633. In other words, the first face 634a forms a side of the arc extinguishing magnet 634 opposite the grid 620. In the illustrated embodiment, the first face 634a can be defined by an upper side of the arc extinguishing magnet 634.

[0354] The second face 634b forms another side of the arc extinguishing magnet 634 facing the barrier plate 636. In other words, the second face 634b forms another side of the arc extinguishing magnet 634 facing the grid 620. In the illustrated embodiment, the second face 634b can be defined by a lower side of the arc extinguishing magnet 634.

[0355] The first face 634a and the second face 634b are configured to face each other. In other words, the first face 634a and the second face 634b are a side and another side of the arc extinguishing magnet 634 facing each other.

[0356] The first face 634a can be magnetized to either one of N-pole or S-pole. In addition, the second face 634b can be magnetized to the other one of N-pole or S-pole. That is, the first face 634a and the second face 634b are magnetized to opposite polarities to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 634a and the second face 634b.

[0357] As described above, the CT magnet portion 500 of the embodiment of the present application includes the CT magnet 530. In the embodiment, a primary magnetic field M.M.F. can be formed between the second face 634b and the first face 531 of the CT magnet portion 500.

[0358] Detailed description about the process of forming the primary magnetic field M.M.F. and the secondary magnetic field S.M.F. by the arc extinguishing magnet 634 will be made later.

[0359] The magnet cover 635 supports the arc extinguishing magnet 634 such that the arc extinguishing magnet 634 disposed on the barrier plate 636 cannot be arbitrarily shaken on the barrier plate 636.

[0360] The magnet cover 635 is located at a lower side of the grid portion 633. In addition, the magnet cover 635 is located at an upper side of the barrier plate 636. The magnet cover 635 can be disposed on the barrier plate 636.

[0361] As described above, the arc extinguishing magnet 634 can also be disposed on the barrier plate 636. That is, the magnet cover 635 can be located on the same plane as the arc extinguishing magnet 634.

[0362] The magnet cover 635 includes a plurality of opening portions. In the illustrated embodiment, the magnet cover 635 includes a first opening portion 635a formed on the rear side and a second opening portion 635b formed on the front side.

[0363] Any one of the first opening portion 635a and the second opening portion 635b of the magnet cover 635, the first opening portion 635a formed on the rear side in the illustrated embodiment, communicates with the through-hole 636a of the barrier plate 636. An electric arc passing through the through-hole 636a can flow toward the grid portion 633 through the first opening portion 635a via the barrier plate 636.

[0364] The arc extinguishing magnet 634 is positioned in the other of the first opening portion 635a and the second opening portion 635b of the magnet cover 635, the second opening portion 635b formed on the front side in the illustrated embodiment. The edges of the magnet cover 635 surrounding the second opening portion 635b formed on the front side of the magnet cover 635 surround the arc extinguishing magnet 634.

[0365] The second opening portion 635b formed on the front side of the magnet cover 635 can be formed in a shape corresponding to the shape of the arc extinguishing magnet 634. In the illustrated embodiment, the arc extinguishing magnet 634 has a rectangular cross section extending in the front-rear direction and the left-right direction.

[0366] Thus, the second opening portion 635b formed on the front side of the magnet cover 635 can also be formed to have a rectangular cross section extending in the front-rear direction and the left-right direction.

[0367] The arc extinguishing magnet 634 can not be shaken in the front-rear direction or the left-right direction in a state of being seated on the barrier plate 636 by the magnet cover 635. Meanwhile, an electric arc passing through the through-hole 636a of the barrier plate 636 can flow toward the grid portion 633 via the opening portion formed in the magnet cover 635.

[0368] The magnet cover 635 can be formed of a heat-resistant material. This is to prevent the magnet cover 635 from being damaged or deformed by an electric arc passing through the through-hole 636a of the barrier plate 636.

[0369] The magnet cover 635 can be formed of an insulating material. This is to prevent a magnetic field formed by the arc extinguishing magnet 634 from being disturbed or an electric arc in flow from being attracted by the magnet cover 635.

[0370] In one embodiment, the magnet cover 635 can be formed of a reinforced plastic or an acrylic material or the like.

[0371] The barrier plate 636 is positioned on the lower side of the magnet cover 635.

[0372] The barrier plate 636 supports the arc extinguishing magnet 634 and the magnet cover 635 on the lower side. Thus, the arc extinguishing magnet 634 housed in the internal space of the cover main body 631 is not exposed to the generated arc. Therefore, it is possible to prevent the arc extinguishing magnet 634 from being damaged by the arc.

[0373] In addition, the barrier plate 636 provides a passage for the arc passing through the space formed between the grids 620 to flow toward the mesh portion 633.

[0374] The barrier plate 636 is housed in the housing space of the cover main body 631. In the housing space of the cover main body 631, the barrier plate 636 is located on the lowermost side.

[0375] In the illustrated embodiment, the barrier plate 636 is formed in a rectangular cross section having a length in the front-rear direction greater than a length in the left-right direction. The shape of the barrier plate 636 can vary depending on the cross-sectional shape of the housing space of the cover main body 631.

[0376] The grid 620 is located on the lower side of the barrier plate 636. In one embodiment, the upper side end portion of the grid 620, that is, the side end portion of the grid 620 toward the barrier plate 636 can be in contact with the barrier plate 636.

[0377] The barrier plate 636 includes a through-hole 636a.

[0378] The through-hole 636a is a passage for the arc passing through the spaces formed by the plurality of grids 620 to flow into the housing space of the cover main body 631. The through-hole 636a is formed in a direction perpendicular to the barrier plate 636, that is, in the up-down direction in the illustrated embodiment.

[0379] The through-hole 636a can be formed in a plurality. The plurality of through-holes 636a can be arranged apart from each other.

[0380] The through-hole 636a can be located in a position deviated to one side in the barrier plate 636. In the illustrated embodiment, the through-hole 636a is located on the opposite side of the arc extinguishing magnet 634, that is, on the rear side of the barrier plate 636.

[0381] The through-hole 636a is not blocked by the arc extinguishing magnet 634 and can be arranged at any position that can communicate with the first opening portion 635a formed in the magnet cover 635. The through-hole 636a communicates with the first opening portion 635a.

[0382] The arc guide 640 guides the generated arc to flow toward the grid 620. By the arc guide 640, it is possible to prevent the generated arc from flowing toward the support plate 610 to cause damage to the support plate 610.

[0383] The arc guide 640 is located on the side of the support plate 610 facing the fixed contact 311 and the movable contact 321. In the illustrated embodiment, the arc guide 640 is located on the lower side of the support plate 610.

[0384] A plurality of arc guides 640 can be provided. The plurality of arc guides 640 can be combined with each support plate 610. In the illustrated embodiment, the arc guide 640 is provided with two and combined with each support plate 610, respectively. The two arc guides 640 are configured to face each other.

[0385] The arc guide 640 is combined with the support plate 610. The combination can be achieved by an additional fastening member.

[0386] The arc guide 640 can be formed of a heat-resistant material. This is to prevent damage and deformation due to the generated arc. In an embodiment, the arc guide 640 can be formed of a ceramic material.

[0387] The arc guide 640 is configured to surround a portion of the pointed portion formed at both sides of the grid 620, the left and right directions in the illustrated embodiment. Thus, the arc guided by the arc guide 640 does not concentrate on any portion in the grid 620.

[0388] The arc guide 640 can extend in the extension direction of the support plate 610, the front and rear directions in the illustrated embodiment. That is, the arc guide 640 can extend between the grid 620 located at the most front side and the grid 620 located at the most rear side.

[0389] The arc guide 640 includes a first extension 641 and a second extension 642.

[0390] The first extension 641 is a portion of the arc guide 640 combined with the support plate 610. The first extension 641 is located on the side of the support plate 610 facing the fixed contact 310, the lower side in the illustrated embodiment. The first extension 641 can be combined with the support plate 610 using a fastening member.

[0391] The first extension 641 extends in the direction toward the grid 620, the upper side in the illustrated embodiment. In an embodiment, the first extension 641 can be in contact with the support plate 610 and extend. In another embodiment, the first extension 641 can extend in parallel with the support plate 610.

[0392] The second extension 642 extends from the end of the first extension 641.

[0393] The second extension portion 642 is formed to surround a part of the pointed portion formed at the end portion of the grid 620 in the left-right direction. The second extension portion 642 is formed to extend at a predetermined angle with the first extension portion 641. In one embodiment, the second extension portion 642 can be formed to extend at an obtuse angle with the first extension portion 641.

[0394] In another embodiment, the second extension portion 642 can be formed to extend in parallel with the pointed portion formed at the end portion of the grid 620 in the left-right direction.

[0395] The arc flow channel 650 guides the generated arc to flow toward the grid 620. By the arc guide 640, it is possible to prevent the generated arc from advancing toward the side wall of the cover portion 100 beyond the grid 620. Thereby, it is possible to prevent the cover portion 100 from being damaged by the generated arc.

[0396] The arc flow channel 650 is located at the side of the support plate 610 toward the fixed contact 311 and the movable contact 321. In the illustrated embodiment, the arc flow channel 650 is located at the lower side of the support plate 610.

[0397] The arc flow channel 650 is located at the other side of the support plate 610 opposite to the fixed contact 311. Specifically, the arc flow channel 650 is located at the rear side of the lower side of the support plate 610, thereby being opposite to the fixed contact 311 located at the front side of the support plate 610.

[0398] The arc flow channel 650 is combined with the support plate 610. The combination can be achieved by inserting the protrusion formed at the end portion of the arc flow channel 650 in the left-right direction into the through hole formed in the support plate 610.

[0399] The arc flow channel 650 can be formed of an electrically conductive material. This is to effectively guide the arc by applying attractive force to the arc in flow. In one embodiment, the arc flow channel 650 can be formed of copper, iron, or an alloy including them.

[0400] The arc flow channel 650 extends toward the grid 620 by a predetermined length. In one embodiment, the arc flow channel 650 can be configured to cover the grid 620 located farthest from the fixed contact 311 at the rear side, in the illustrated embodiment, the grid 620 located at the most rear side.

[0401] Thereby, the arc cannot extend beyond the grid 620 located at the most rear side, thereby making it possible to prevent the cover portion 100 from being damaged. In addition, it is possible to effectively guide the generated arc toward the grid 620.

[0402] Figures 19 to 30

[0403] Referring to 7. Explanation of the path A.P of the electric arc formed by the air circuit breaker 10 according to each embodiment of the present application , the air circuit breaker 10 according to another embodiment of the present application includes the arc extinguishing portion 700.

[0404] The arc extinguishing portion 700 is configured to extinguish an arc generated due to the separation of the fixed contact 311 and the movable contact 321. The generated arc can be extinguished and cooled in the process of passing through the arc extinguishing portion 700, and then discharged to the outside of the air circuit breaker 10.

[0405] The arc extinguishing portion 700 is combined with the cover portion 100. One side of the arc extinguishing portion 700 for discharging the arc can be exposed to the outside of the cover portion 100. In the illustrated embodiment, the upper side of the arc extinguishing portion 700 is exposed to the outside of the cover portion 100.

[0406] A part of the arc extinguishing portion 700 is accommodated in the cover portion 100. The remaining part of the arc extinguishing portion 700 other than the part exposed to the outside can be accommodated in the internal space of the cover portion 100. In the illustrated embodiment, a part of the arc extinguishing portion 700 is accommodated in the upper side of the upper cover 110.

[0407] The above-described configuration can vary depending on the positions of the fixed contact 311 and the movable contact 312. That is, the arc extinguishing portion 700 can be located adjacent to the fixed contact 311 and the movable contact 312. Therefore, the arc extending along the movable contact 312 rotating in the direction away from the fixed contact 311 can easily enter the arc extinguishing portion 700.

[0408] The arc extinguishing portion 700 can be provided in plural. The plural arc extinguishing portions 700 can be physically or electrically separated from each other. In the illustrated embodiment, the arc extinguishing portion 700 is provided in three. This is also because, as in the foregoing case, three-phase currents flow in the air circuit breaker 10 of the embodiment of the present application.

[0409] That is, each of the arc extinguishing portions 700 is located adjacent to each of the fixed contacts 311 and the movable contacts 321. In the illustrated embodiment, each of the arc extinguishing portions 700 is adjacent to the upper side of each of the fixed contacts 311 and the movable contacts 321.

[0410] It can be understood that each of the arc extinguishing portions 700 is configured to extinguish an arc generated due to the disconnection of each of the phase currents flowing in each of the disconnecting portions 300.

[0411] The arc extinguishing portions 700 can be arranged adjacent to each other. In the illustrated embodiment, the three arc extinguishing portions 700 are arranged side by side in the left-right direction of the air circuit breaker 10.

[0412] In the present embodiment, the arc extinguishing portion 700 includes first to third arc magnet portions 771, 772, 773. The first to third arc magnet portions 771, 772, 773 form an arc path A.P. for the generated arc to effectively flow toward the arc extinguishing portion 700 by forming a main magnetic field M.M.F and a secondary magnetic field S.M.F. Details thereof will be described later.

[0413] In the illustrated embodiment, the arc extinguishing portion 700 includes a support plate 710, a grid 720, a grid cover 730, an arc guide 740, an arc runner 750, a magnet housing 760, and an arc extinguishing magnet portion 770.

[0414] The support plate 710 forms both sides of the arc extinguishing portion 700, in the illustrated embodiment, the right side and the left side. The support plate 710 is combined with each of the constituent elements of the arc extinguishing portion 700, and supports the constituent elements.

[0415] Specifically, the support plate 710 is combined with the grid 720, the grid cover 730, the arc guide 740, and the arc runner 750. In addition, the support plate 710 is combined with the magnet housing 760.

[0416] The support plate 710 is provided in plural. The plural support plates 710 can be arranged so as to be spaced apart from each other and to face each other. In the illustrated embodiment, the support plate 710 is provided in two, and forms the right side and the left side of the arc extinguishing portion 700, respectively.

[0417] The support plate 710 can be formed of an insulating material. This is in order to prevent the generated arc from flowing toward the support plate 710.

[0418] The support plate 710 can be formed of a heat-resistant material. This is in order to prevent the support plate 710 from being damaged or deformed by the generated arc.

[0419] Plural through-holes are formed in the support plate 710. The grid 720 and the arc runner 750 can be inserted and combined in a part of the through-holes.

[0420] In addition, another part of the through-holes can be through-combined with fastening members that fasten the grid cover 730 and the arc guide 740 to the support plate 710.

[0421] Further, still another part of the through-holes can be through-combined with fastening members 762c, 763c for fastening the second arc extinguishing magnet portion 772 to the third arc extinguishing magnet portion 773 to the support plate 710.

[0422] In the illustrated embodiment, the support plate 710 is in a plate shape in which plural corners are formed at the apex. The support plate 710 can be provided in any form that forms both sides of the arc extinguishing portion 700 and is capable of supporting each of the constituent elements of the arc extinguishing portion 700.

[0423] The support plate 710 is combined with the grid 720. Specifically, the insertion protrusions provided at both sides of the grid 720, in the illustrated embodiment, the right end portion and the left end portion, are inserted and combined in a part of the through-holes of the support plate 710.

[0424] The support plate 710 is combined with the grid cover 730. Specifically, the grid cover 730 is combined on the upper side of the support plate 710. The combination can be achieved by insertion combination of the support plate 710 and the grid cover 730 or by an additional fastening member.

[0425] The support plate 710 is combined with the arc guide 740. Specifically, the arc guide 740 is combined on the lower side of the support plate 710, i.e., the side opposite to the grid cover 730. The combination can be achieved by an additional fastening member.

[0426] The support plate 710 is combined with the arc runner 750. Specifically, the arc runner 750 is combined on the rear side of the support plate 710, i.e., the side opposite to the fixed contact 311. The combination can be achieved by an additional fastening member.

[0427] The support plate 710 is combined with the magnet housing 760. Specifically, the support plate 710 can be combined with the second and third accommodation portions 762 and 763 of the magnet housing 760 by the second and third fastening members 762c and 763c.

[0428] The grid 720 guides the arc generated due to the separation of the fixed contact 311 and the movable contact 321 toward the arc extinguishing portion 700.

[0429] The guidance can be achieved by the magnetic force generated by the grid 720. In addition, the guidance can be achieved by the arc extinguishing magnet portion 770 provided to the arc extinguishing portion 700.

[0430] The grid 720 can be formed of a material having magnetism. This is to apply an attractive force to the arc that is the flow of electrons.

[0431] The grid 720 can be provided in plural. The plural grids 720 can be spaced apart from each other and stacked. In the illustrated embodiment, the grid 720 is provided in ten and stacked in the front-rear direction.

[0432] The space formed by the plural grids 720 spaced apart from each other divides the inflowing arc into smaller and flows. Thereby, the pressure of the arc, the moving speed of the arc, and the arc extinguishing speed can be increased.

[0433] The arc runner 750 is located adjacent to the grid 720 farthest from the fixed contact 311 among the plural grids 720, i.e., the grid 720 on the rear side in the illustrated embodiment.

[0434] The end portion of the grid 720 in the width direction, i.e., the left-right direction in the illustrated embodiment, can be formed protruding toward the fixed contact 311, i.e., the lower side. That is, the grid 720 is formed in a peak shape with the end portion in the left-right direction toward the lower side.

[0435] Thus, the generated arc can effectively travel toward the end portions of the grid 720 in the left-right direction, and thus can easily flow to the arc extinguishing portion 700.

[0436] The arc guide 740 is positioned outside the end portions of the grid 720 in the left-right direction, and in the illustrated embodiment, the lower side.

[0437] The grid 720 is combined with the support plate 710. Specifically, the edges of the grid 720 in the width direction, in the illustrated embodiment, the left-right direction, are formed with a plurality of combination protrusions, and the plurality of combination protrusions are formed in the extension direction of the grid 720, in the illustrated embodiment, the up-down direction. The combination protrusions of the grid 720 are inserted into and combined with the through holes formed in the support plate 710.

[0438] A portion of the plurality of grids 720 is inserted into and combined with the grid combination portion 764 of the magnet housing 760.

[0439] Specifically, the end portion of one side, in the illustrated embodiment, the lower side, of a portion of the plurality of grids 720 is inserted into and combined with the grid combination portion 764 of the magnet housing 760.

[0440] As described above, since the grid 720 is positioned above the fixed contact 311, it can also be said that the side of a portion of the grid 720 toward the fixed contact 311 is inserted into the grid combination portion 764.

[0441] Any one or more of the plurality of grids 720 can be combined with the magnet housing 760 that houses the arc extinguishing magnet portion 770 for forming a path of the arc. Specifically, the lower end portion of any one or more of the plurality of grids 720 can be inserted into and combined with the grid combination portion 764 formed in the magnet housing 760.

[0442] In the illustrated embodiment, the lower end portions of the two grids 720 positioned in the center in the front-rear direction, i.e., the fifth and sixth grids 720 from the front side, are inserted into and combined with the grid combination portion 764.

[0443] In addition, on both sides of the two grids 720, in the illustrated embodiment, the left-right direction, the second housing portion 762 and the third housing portion 763 are combined.

[0444] That is, in the illustrated embodiment, the second housing portion 762 is combined on the left side between the two grids 720 positioned in the center in the front-rear direction, i.e., the fifth and sixth grids 720 from the front side. In addition, the third housing portion 763 is combined on the right side between the two grids 720.

[0445] The side of the grid 720 toward the grid cover 730, which is the upper side end portion in the illustrated embodiment, can be positioned adjacent to the grid cover 730. An arc flowing along the grid 720 can be discharged to the outside via the grid cover 730.

[0446] The grid cover 730 forms the upper side of the arc extinguishing portion 700. The grid cover 730 is configured to cover the upper side end portion of the grid 720. An arc that has passed through the spaces formed by the plurality of grids 720 spaced apart from each other can be discharged to the outside of the air circuit breaker 10 via the grid cover 730.

[0447] The grid cover 730 is combined with the support plate 710. At the edges of the grid cover 730 in the width direction, which is the left-right direction in the illustrated embodiment, protrusions that are inserted into the through holes of the support plate 710 can be formed. Alternatively, the grid cover 730 and the support plate 710 can be combined by an additional fastening member.

[0448] The grid cover 730 extends in one direction, which is the front-rear direction in the illustrated embodiment. It will be understood that this direction is the same as the stacking direction of the plurality of grids 720.

[0449] The length of the grid cover 730 in the other direction, which is the width direction in the illustrated embodiment, can be determined in accordance with the length of the plurality of grids 720 in the width direction.

[0450] In the illustrated embodiment, the grid cover 730 includes a cover main body 731, an upper frame 732, and a mesh portion 733.

[0451] The cover main body 731 forms the appearance of the grid cover 730. The cover main body 731 is combined with the support plate 710. In addition, the upper frame 732 is combined with the cover main body 731.

[0452] A prescribed space is formed inside the cover main body 731. This space can be covered by the upper frame 732. The mesh portion 733 is housed in this space. Here, this space can be referred to as a "housing space".

[0453] The housing space communicates with the spaces formed by the spacing of the grids 720. As a result, the housing space communicates with the internal space of the cover portion 100. Thus, an arc generated can flow to the housing space of the cover main body 731 through the spaces formed by the spacing of the grids 720.

[0454] The side of the cover main body 731 toward the grid 720, which is the lower side in the illustrated embodiment, can be in contact with the upper side end portion of the grid 720. In one embodiment, the cover main body 731 can support the upper side end portion of the grid 720.

[0455] The cover main body 731 can be formed of an insulating material. This is to prevent distortion of the magnetic field of the path A.P for forming an arc.

[0456] The cover body 731 can be formed of a heat-resistant material. This is to prevent the cover body 731 from being damaged or deformed due to an arc generated.

[0457] In the illustrated embodiment, the length of the cover body 731 in the front-rear direction is greater than the length in the left-right direction. The shape of the cover body 731 can vary depending on the shape of the support plate 710 and the shape and number of the grids 720.

[0458] On the side of the cover body 731 opposite the grids 720, the upper frame 732 is coupled in the illustrated embodiment on the upper side.

[0459] The upper frame 732 is coupled to the upper side of the cover body 731. The upper frame 732 is configured to cover the accommodation space formed in the cover body 731 and the grid portion 733 accommodated in the accommodation space.

[0460] In the illustrated embodiment, the length of the upper frame 732 in the front-rear direction is greater than the length in the left-right direction. The upper frame 732 can be formed in any shape that stably couples to the upper side of the cover body 731 and is capable of covering the accommodation space and the constituent elements accommodated in the accommodation space.

[0461] A plurality of through holes are formed in the upper frame 732. Through the through holes, arcs that have passed between the grids 720 and have been extinguished can be discharged. In the illustrated embodiment, three through holes are formed in the left-right direction and three rows are formed in the front-rear direction, so that a total of nine through holes are formed. The number of through holes can vary.

[0462] The through holes are located at positions spaced apart from each other. A rib is formed between the through holes. The rib can press the grid portion 733 accommodated in the space of the cover body 731 on the upper side.

[0463] Thus, even if an arc is generated, the grid portion 733 does not arbitrarily come off the accommodation space of the cover body 731.

[0464] The upper frame 732 can be fixedly coupled to the upper side of the cover body 731. In the illustrated embodiment, the upper frame 732 can be fixedly coupled to the upper side of the cover body 731 by a fastening member.

[0465] The grid portion 733 is located between the upper frame 732 and the cover body 731, i.e., on the lower side of the upper frame 732 in the accommodation space of the cover body 731.

[0466] The mesh portion 733 functions as a filter that filters impurities remaining in the arc that is extinguished through the space formed between the grids 720. The extinguished arc can pass through the mesh portion 733 and be discharged to the outside after the remaining impurities are removed.

[0467] That is, the mesh portion 733 functions as a filter.

[0468] The mesh portion 733 includes a plurality of through-holes. Preferably, the size, i.e., the diameter, of the through-holes can be smaller than the diameter of the impurity particles remaining in the arc. In addition, preferably, the diameter of the through-holes is sufficiently large to allow the gas included in the arc to pass therethrough.

[0469] The mesh portion 733 can be provided in plural. The plural mesh portions 733 can be stacked in the up-and-down direction. Thereby, the impurities remaining in the arc that passes through the mesh portion 733 can be effectively removed.

[0470] The mesh portion 733 is accommodated in the accommodation space formed in the inside of the cover body 731. The shape of the mesh portion 733 can be determined according to the shape of the accommodation space.

[0471] The mesh portion 733 is positioned at the lower side of the upper frame 732. The plurality of through-holes formed in the mesh portion 733 communicate with the plurality of through-holes formed in the upper frame 732. Thereby, the arc that passes through the mesh portion 733 can be discharged to the outside through the upper frame 732.

[0472] The plurality of through-holes formed in the mesh portion 733 communicate with the space formed by the grids 720. As a result, the plurality of through-holes formed in the mesh portion 733 communicate with the inside space of the cover portion 100.

[0473] Although not shown, a barrier plate (not shown) can be positioned at the lower side of the mesh portion 733. The barrier plate (not shown) is formed with a plurality of through-holes (not shown) so as to communicate the inside space of the cover portion 100 and the mesh portion 733.

[0474] The arc guide 740 guides the generated arc to flow toward the grids 720. By the arc guide 740, it is possible to prevent the generated arc from flowing toward the support plate 710 to cause damage to the support plate 710.

[0475] The arc guide 740 is positioned at the side of the support plate 710 toward the fixed contact 311 and the movable contact 321. In the illustrated embodiment, the arc guide 740 is positioned at the lower side of the support plate 710.

[0476] The arc guide 740 is provided with a plurality of. The plurality of arc guides 740 can be combined with each support plate 710. In the illustrated embodiment, the arc guide 740 is provided with two, and is combined with each support plate 710, respectively. The two arc guides 740 are configured to face each other.

[0477] The arc guide 740 is combined with the support plate 710. The combination can be achieved by an additional fastening member.

[0478] The arc guide 740 can be formed of a heat-resistant material. This is to prevent damage and deformation due to the generated arc. In an embodiment, the arc guide 740 can be formed of a ceramic material.

[0479] The arc guide 740 is configured to surround a portion of the pointed portion formed at both sides of the grid 720, the left and right directions in the illustrated embodiment. Thus, the arc guided by the arc guide 740 does not concentrate on any portion of the grid 720.

[0480] The arc guide 740 can extend in the extension direction of the support plate 710, the front and rear directions in the illustrated embodiment. That is, the arc guide 740 can extend between the grid 720 located at the most front side and the grid 720 located at the most rear side.

[0481] The arc guide 740 includes a first extension 741 and a second extension 742.

[0482] The first extension 741 is a portion of the arc guide 740 combined with the support plate 710. The first extension 741 is located at the side of the support plate 710 facing the fixed contact 310, the lower side in the illustrated embodiment. The first extension 741 can be combined with the support plate 710 by a fastening member.

[0483] The first extension 741 extends in the direction toward the grid 720, the upper side in the illustrated embodiment. In an embodiment, the first extension 741 can be in contact with the support plate 710 and extend. In another embodiment, the first extension 741 can extend in parallel with the support plate 710.

[0484] The second extension 742 extends from the end of the first extension 741.

[0485] The second extension 742 is formed to surround a portion of the pointed portion formed at the end of the grid 720 in the left and right directions. The second extension 742 extends at a prescribed angle with the first extension 741. In an embodiment, the second extension 742 can extend at an obtuse angle with the first extension 741.

[0486] In another embodiment, the second extension 742 can extend in parallel with a pointed portion formed at the end of the grid 720 in the left-right direction.

[0487] The arc flow channel 750 guides the generated arc to flow toward the grid 720. By the arc guide 740, it is possible to prevent the generated arc from advancing toward the side wall of the cover portion 100 beyond the grid 720. Thereby, it is possible to prevent the cover portion 100 from being damaged by the generated arc.

[0488] The arc flow channel 750 is located at the side of the support plate 710 toward the fixed contact 311 and the movable contact 321. In the illustrated embodiment, the arc flow channel 750 is located at the lower side of the support plate 710.

[0489] The arc flow channel 750 is located at the other side of the support plate 710 opposite to the fixed contact 311. Specifically, the arc flow channel 750 is located at the rear side of the lower side of the support plate 710, thereby being opposite to the fixed contact 311 located at the front side of the support plate 710.

[0490] The arc flow channel 750 is combined with the support plate 710. The combination can be achieved by inserting a protrusion formed at the end of the arc flow channel 750 in the left-right direction into a through-hole formed in the support plate 710.

[0491] The arc flow channel 750 can be formed of an electrically conductive material. This is to effectively guide the arc by applying an attractive force to the arc in flow. In an embodiment, the arc flow channel 750 can be formed of copper, iron, or an alloy including them.

[0492] The arc flow channel 750 extends toward the grid 720 by a prescribed length. In an embodiment, the arc flow channel 750 can be configured to cover the grid 720 located farthest from the fixed contact 311 at the rear side, in the illustrated embodiment, the grid 720 located at the rearmost side.

[0493] Thereby, the arc does not extend beyond the grid 720 located at the rearmost side, thereby making it possible to prevent the cover portion 100 from being damaged. In addition, it is possible to effectively guide the generated arc toward the grid 720.

[0494] The magnet housing 760 accommodates an arc extinguishing magnet portion 770 that forms a main magnetic field M.M.F and a secondary magnetic field S.M.F in the arc extinguishing portion 700.

[0495] In addition, the magnet housing 760 can be combined with the support plate 710 or the grid 720, thereby making it possible to stably combine the arc extinguishing magnet portion 770 to the arc extinguishing portion 700.

[0496] The magnet housing 760 extends in a direction, in the illustrated embodiment, the left-right direction. The length of the extension of the magnet housing 760 can be determined according to the length of the extension of the grid 720 in the width direction, i.e., the left-right direction.

[0497] In one embodiment, the magnet housing 760 can extend such that one side end portion and the other side end portion thereof are in contact with the respective support plates 710 opposite to each other. That is, the magnet housing 760 extends between the respective support plates 710 opposite to each other.

[0498] The magnet housing 760 can be formed of an insulating material. This is to prevent the main magnetic field M.M.F and the secondary magnetic field S.M.F formed by the arc extinguishing magnet portion 770 from being subjected to magnetic interference.

[0499] The magnet housing 760 can be formed of a heat-resistant material. This is to prevent the magnet housing 760 from being damaged due to the arc of high temperature and high pressure.

[0500] In one embodiment, the magnet housing 760 can be formed of synthetic resin or reinforced plastic.

[0501] In the illustrated embodiment, the magnet housing 760 includes a first accommodation portion 761, a second accommodation portion 762, a third accommodation portion 763, a grid coupling portion 764, and an arc inflow portion 765.

[0502] The first accommodation portion 761 accommodates the first arc extinguishing magnet 771 of the arc extinguishing magnet portion 770.

[0503] The first accommodation portion 761 forms one side of the magnet housing 760, in the illustrated embodiment, the lower side. In other words, the first accommodation portion 761 is formed at the side of the magnet housing 760 facing the fixed contact 311.

[0504] The first accommodation portion 761 is formed protruding toward a direction away from the grid 720, in the illustrated embodiment, the lower side. The protruding length of the first accommodation portion 761 can be determined according to the position of the lower end portion of the support plate 710. That is, the lower end portion of the first accommodation portion 761 can be positioned at a position further away from the fixed contact 311 than the lower end portion of the support plate 710.

[0505] The first accommodation portion 761 can be positioned at a central portion of the direction in which the magnet housing 760 extends, in the illustrated embodiment, the left-right direction. In other words, the first accommodation portion 761 can be positioned between the second accommodation portion 762 and the third accommodation portion 763.

[0506] The first accommodation portion 761 can be positioned at the lower side of the grid 720. Specifically, the first accommodation portion 761 is positioned at the side of the grid 720 facing the fixed contact 311, in the illustrated embodiment, the lower side.

[0507] On the side of the first accommodating portion 761 facing the grid 720, the grid coupling portion 764 is formed in the illustrated embodiment on the upper side. In addition, on both sides of the first accommodating portion 761, the arc inflow portions 765 are formed in the illustrated embodiment on the right and left sides.

[0508] The first accommodating portion 761 includes a first accommodating groove 761a, a first fastening hole 761b, a first fastening member 761c, and a cover portion 761d.

[0509] The first accommodating groove 761a is a space that accommodates the first arc extinguishing magnet 771 of the arc extinguishing magnet portion 770. The first accommodating groove 761a is recessed on the side of the first accommodating portion 761 opposite the arc flow passage 750, in the illustrated embodiment on the front side.

[0510] The first accommodating groove 761a can be formed at any position at which the first arc extinguishing magnet 771 can be accommodated. For example, the first accommodating groove 761a can be formed at any position on the rear side or lower side of the first accommodating portion 761 at which a space can be formed by recessing.

[0511] An opening portion is formed on the side of the first accommodating groove 761a, in the illustrated embodiment on the front side. The first arc extinguishing magnet 771 can be accommodated in the first accommodating groove 761a through the opening portion.

[0512] As described above, the first accommodating groove 761a can also be formed at another position of the first accommodating portion 761. In this case, an opening portion is formed on the outside of the first accommodating groove 761a, which can function as a passage through which the first arc extinguishing magnet 771 is accommodated in the first accommodating groove 761a. In the illustrated embodiment, the first accommodating groove 761a is formed to have a rectangular cross section. The shape of the first accommodating groove 761a can vary depending on the shape of the first arc extinguishing magnet 771.

[0513] After the first arc extinguishing magnet 771 is accommodated in the first accommodating groove 761a, the first accommodating groove 761a can be covered by the cover portion 761d. Thereby, the first arc extinguishing magnet 771 accommodated in the first accommodating groove 761a can be prevented from rattling and coming off arbitrarily.

[0514] The first fastening hole 761b is a space into which the first fastening member 761c for fixing the cover portion 761d to the first accommodating portion 761 is inserted. The first fastening hole 761b is recessed in the first accommodating portion 761. In one embodiment, the first fastening hole 761b can be formed through the first accommodating portion 761.

[0515] The first fastening hole 761b is located adjacent to the first accommodation groove 761a. In the illustrated embodiment, two first fastening holes 761b are provided, each of which is located on the right and left sides of the first accommodation groove 761a, respectively.

[0516] The number and location of the first fastening hole 761b can vary depending on the number and location of the fastening hole formed in the cover portion 761d.

[0517] The first fastening member 761c fastens the first accommodation portion 761 and the cover portion 761d.

[0518] The first fastening member 761c is inserted into or fastened to the first accommodation portion 761. Thereby, the first accommodation portion 761 and the cover portion 761d can be stably coupled.

[0519] The first fastening member 761c can be provided in any form capable of fastening two or more members. In one embodiment, the first fastening member 761c can be a screw member or a rivet member, etc.

[0520] The first fastening member 761c can be provided in plural. In the illustrated embodiment, two first fastening members 761c are provided. The number of the first fastening member 761c can be determined depending on the number of the first fastening hole 761b of the first accommodation portion 761 and the number of the through hole formed in the cover portion 761d.

[0521] The cover portion 761d is coupled with the first accommodation portion 761. After the first arc extinguishing magnet 771 is accommodated in the first accommodation groove 761a, the cover portion 761d can cover the first accommodation groove 761a. Thereby, any shaking and disengagement of the first arc extinguishing magnet 771 can be prevented.

[0522] The cover portion 761d can be formed in a shape corresponding to the first accommodation portion 761. In one embodiment, the shape of the cover portion 761d can be the same as the cross-sectional shape of the first accommodation portion 761.

[0523] In the illustrated embodiment, the cross-section of the first accommodation portion 761 and the cross-section of the cover portion 761d are in a trapezoidal shape having each of the upper and lower sides as a base and a top, but the shape thereof can be changed.

[0524] The through hole is formed in the cover portion 761d. The first fastening member 761c is inserted into or fastened to the through hole. Thereby, the cover portion 761d and the first accommodation portion 761 can be stably coupled.

[0525] The through hole can be formed in plural. The plural through holes can be arranged apart from each other. In the illustrated embodiment, two through holes are formed and arranged apart in the left and right directions of each cover portion 761d.

[0526] The number and position of the through holes can vary depending on the number and position of the first fastening holes 761b of the first accommodation portion 761.

[0527] The second accommodation portion 762 is located on one side of the first accommodation portion 761, in the illustrated embodiment, the left side. The first accommodation portion 761 and the second accommodation portion 762 are continuous.

[0528] The second accommodation portion 762 accommodates the second arc extinguishing magnet 772 of the arc extinguishing magnet portion 770.

[0529] The second accommodation portion 762 forms the other side of the magnet housing 760, in the illustrated embodiment, the left side. In other words, the second accommodation portion 762 is located adjacent to any one of the support plates 710 opposite to each other, in the illustrated embodiment, the support plate 710 located on the left side.

[0530] The second accommodation portion 762 is located on one side of the first accommodation portion 761, in the illustrated embodiment, the left side. The second accommodation portion 762 extends in a direction away from the first accommodation portion 761.

[0531] In other words, the second accommodation portion 762 extends toward the left side edge of the support plate 710 or the grid 720. The end of the second accommodation portion 762 can be in contact with the support plate 710.

[0532] The second accommodation portion 762 is configured to be opposite to the third accommodation portion 763 across the first accommodation portion 761. In an embodiment, the second accommodation portion 762 and the third accommodation portion 763 can be formed symmetrically to each other.

[0533] The second accommodation portion 762 can be located on one side of the grid 720. Specifically, the second accommodation portion 762 is located on the side of the grid 720 toward the support plate 710 located on the left side of the support plates 710, in the illustrated embodiment, the left side.

[0534] The grid joint portion 764 is formed between the second accommodation portion 762 and the third accommodation portion 763. In addition, the arc inflow portion 765 is formed between the second accommodation portion 762 and the third accommodation portion 763.

[0535] The second accommodation portion 762 includes a second accommodation groove 762a, a second fastening hole 762b, and a second fastening member 762c.

[0536] The second accommodation groove 762a is a space for accommodating the second arc extinguishing magnet 772 of the arc extinguishing magnet portion 770. The second accommodation groove 762a is recessed at the end of the second accommodation portion 762, in the illustrated embodiment, the left side.

[0537] In other words, the second accommodation groove 762a is recessed on the side of the second accommodation portion 762 facing the support plate 710, which is the left side in the illustrated embodiment.

[0538] An opening portion is formed on the side of the second accommodation groove 762a, which is the left side in the illustrated embodiment. The second arc extinguishing magnet 772 can be accommodated in the second accommodation groove 762a through the opening portion.

[0539] In the illustrated embodiment, the second accommodation groove 762a is formed to have a rectangular cross section. The shape of the second accommodation groove 762a can vary depending on the shape of the second arc extinguishing magnet 772.

[0540] After the second arc extinguishing magnet 772 is accommodated in the second accommodation groove 762a, the second accommodation groove 762a can be covered by the support plate 710. Thereby, it is possible to prevent the second arc extinguishing magnet 772 accommodated in the second accommodation groove 762a from shaking and arbitrarily coming off.

[0541] The second fastening hole 762b is a space into which a second fastening member 762c for fixing the support plate 710 to the second accommodation portion 762 is inserted. The second fastening hole 762b is recessed in the second accommodation portion 762. In an embodiment, the second fastening hole 762b can be formed to penetrate the second accommodation portion 762.

[0542] The second fastening hole 762b is located adjacent to the second accommodation groove 762a. In the illustrated embodiment, two second fastening holes 762b are formed, and each of the second fastening holes 762b is located on the upper side and the lower side of the second accommodation groove 762a, respectively.

[0543] The number and the position of the second fastening hole 762b can vary depending on the number and the position of the fastening hole formed in the support plate 710.

[0544] The second fastening member 762c fastens the second accommodation portion 762 and the support plate 710.

[0545] The second fastening member 762c is combined to the support plate 710 in penetration. In addition, the second fastening member 762c is inserted or combined to the second accommodation portion 762 in penetration. Thereby, it is possible to stably combine the second accommodation portion 762 and the support plate 710.

[0546] The second fastening member 762c can be provided in any form capable of fastening two or more members. In an embodiment, the second fastening member 762c can be a screw member or a rivet member, or the like.

[0547] The second fastening member 762c can be provided in plural. In the illustrated embodiment, the second fastening member 762c is provided in two. The number of the second fastening member 762c can be determined according to the number of the second fastening holes 762b of the second housing portion 762 and the number of the through holes formed in the support plate 710.

[0548] The third housing portion 763 houses the third arc extinguishing magnet 773 of the arc extinguishing magnet portion 770.

[0549] The third housing portion 763 forms the other side of the magnet housing 760, which is the right side in the illustrated embodiment. In other words, the third housing portion 763 is located adjacent to the other of the support plates 710 opposite to each other, which is the right side support plate 710 in the illustrated embodiment.

[0550] The third housing portion 763 is located on the other side of the first housing portion 761, which is the right side in the illustrated embodiment. The third housing portion 763 extends in a direction away from the first housing portion 761.

[0551] In other words, the third housing portion 763 extends toward the right side edge of the support plate 710 or the grid 720. The end of the third housing portion 763 can be in contact with the support plate 710.

[0552] The third housing portion 763 is configured to be opposite to the second housing portion 762 across the first housing portion 761. In an embodiment, the third housing portion 763 and the second housing portion 762 can be formed symmetrically to each other.

[0553] The third housing portion 763 can be located on one side of the grid 720. Specifically, the third housing portion 763 is located on the side of the grid 720 toward the right side support plate 710 of the support plates 710, which is the right side in the illustrated embodiment.

[0554] The grid joining portion 764 is formed between the third housing portion 763 and the second housing portion 762. In addition, the arc inflow portion 765 is formed between the third housing portion 763 and the second housing portion 762.

[0555] The third housing portion 763 includes a third housing groove 763a, a third fastening hole 763b, and a third fastening member 763c.

[0556] The third housing groove 763a is a space that houses the third arc extinguishing magnet 773 of the arc extinguishing magnet portion 770. The third housing groove 763a is recessed at the end of the third housing portion 763, which is the right side in the illustrated embodiment.

[0557] In other words, the third housing groove 763a is recessed at the side of the third housing portion 763 toward the support plate 710, which is the right side in the illustrated embodiment.

[0558] An opening portion is formed at the one side of the third accommodation groove 763a, which is the right side in the illustrated embodiment. The third arc extinguishing magnet 773 can be accommodated in the third accommodation groove 763a through the opening portion.

[0559] In the illustrated embodiment, the third accommodation groove 763a is formed to have a rectangular cross section. The shape of the third accommodation groove 763a can vary according to the shape of the third arc extinguishing magnet 773.

[0560] After the third arc extinguishing magnet 773 is accommodated in the third accommodation groove 763a, the third accommodation groove 763a can be covered by the support plate 710. Thereby, it is possible to prevent the third arc extinguishing magnet 773 accommodated in the third accommodation groove 763a from shaking and being arbitrarily detached.

[0561] The third fastening hole 763b is a space into which a third fastening member 763c for fixing the support plate 710 to the third accommodation portion 763 is inserted. The third fastening hole 763b is recessed in the third accommodation portion 763. In one embodiment, the third fastening hole 763b can be through-formed in the third accommodation portion 763.

[0562] The third fastening hole 763b is located adjacent to the third accommodation groove 763a. In the illustrated embodiment, two third fastening holes 763b are formed, and each of the third fastening holes 763b is located at the upper side and the lower side of the third accommodation groove 763a, respectively.

[0563] The number and the location of the third fastening hole 763b can vary according to the number and the location of the fastening hole formed in the support plate 710.

[0564] The third fastening member 763c fastens the third accommodation portion 763 and the support plate 710.

[0565] The third fastening member 763c is through-coupled to the support plate 710. Also, the third fastening member 763c is inserted or through-coupled to the third accommodation portion 763. Thereby, it is possible to stably couple the third accommodation portion 763 and the support plate 710.

[0566] The third fastening member 763c can be provided in any form capable of fastening two or more members. In one embodiment, the third fastening member 763c can be a screw member or a rivet member, etc.

[0567] The third fastening member 763c can be provided in plural. In the illustrated embodiment, the third fastening member 763c is provided in two. The number of the third fastening member 763c can be determined according to the number of the third fastening hole 763b of the third accommodation portion 763 and the number of the through hole formed in the support plate 710.

[0568] The first receiving portion 761, the second receiving portion 762, and the third receiving portion 763 can be located at predetermined heights with respect to the up-down direction.

[0569] Specifically, the first receiving portion 761 can be located at a lower position than the second receiving portion 762 and the third receiving portion 763.

[0570] That is, the distance between the first receiving portion 761 and the grid cover 730 can be greater than the distance between the second receiving portion 762 and the grid cover 730 or the distance between the third receiving portion 763 and the grid cover 730. In an embodiment, the distance can be the shortest distance, i.e., the vertical distance.

[0571] In other words, the distance between the first receiving portion 761 and the fixed contact 311 can be less than the distance between the second receiving portion 762 and the fixed contact 311 or the distance between the third receiving portion 763 and the fixed contact 311. In an embodiment, the distance can be the shortest distance, i.e., the vertical distance.

[0572] In addition, the second receiving portion 762 and the third receiving portion 763 can be located at the same height with respect to the up-down direction.

[0573] That is, the distance between the second receiving portion 762 and the grid cover 730 can be the same as the distance between the third receiving portion 763 and the grid cover 730. In an embodiment, the distance can be the shortest distance, i.e., the vertical distance.

[0574] In other words, the distance between the second receiving portion 762 and the fixed contact 311 can be the same as the distance between the third receiving portion 763 and the fixed contact 311. In an embodiment, the distance can be the shortest distance, i.e., the vertical distance.

[0575] Accordingly, the electric arc generated and extended from the fixed contact 311 can be guided to the arc extinguishing portion 700 by the magnetic field formed by the first arc extinguishing magnet 771 of the first receiving portion 761.

[0576] In addition, the guided electric arc can be guided by the magnetic field formed by the second arc extinguishing magnet 772 and the third arc extinguishing magnet 773 of the second receiving portion 762 and the third receiving portion 763, thereby passing through between the grids 720 and being extinguished.

[0577] The grid coupling portion 764 is a portion where the magnet housing 760 is coupled with the grid 720. Specifically, the grid 720 is inserted and coupled to the grid coupling portion 764.

[0578] The grid coupling portion 764 is recessed on the other side surface of the magnet housing 760. Specifically, the grid coupling portion 764 is recessed on the other side, which is the upper side in the illustrated embodiment, of the magnet housing 760 opposite the side on which the first accommodating portion 761 is formed.

[0579] The grid coupling portion 764 is recessed by a prescribed length. Preferably, the grid coupling portion 764 is sufficiently recessed to a degree capable of accommodating a portion of the lower side of the grid 720.

[0580] The grid coupling portion 764 extends between the second accommodating portion 762 and the third accommodating portion 763. In the illustrated embodiment, the grid coupling portion 764 is formed so as to extend in the left-right direction. It will be appreciated that the direction in which the grid coupling portion 764 extends is the same as the direction in which the grid 720 extends between the respective support plates 710.

[0581] The grid coupling portion 764 extends by a prescribed length. In the illustrated embodiment, the left end portion of the grid coupling portion 764 is adjacent to the left end portion of the arc inflow portion 765 formed on the left side in the left-right direction. In addition, the right end portion of the grid coupling portion 764 is adjacent to the right end portion of the arc inflow portion 765 formed on the right side in the left-right direction.

[0582] Preferably, the grid coupling portion 764 extends by a length capable of accommodating a portion of the side of the grid 720 facing the fixed contact 311, which is the lower side in the illustrated embodiment.

[0583] The interior of the grid coupling portion 764 can be formed with a step. In the illustrated embodiment, each end portion in the left-right direction, which is the direction in which the grid coupling portion 764 extends, is recessed by a length smaller than the remaining portion. In one embodiment, the respective end portions of the grid coupling portion 764 can be formed so as to penetrate in the up-down direction of the magnet housing 760.

[0584] Accordingly, the end portions of the grid 720 inserted into the grid coupling portion 764 can penetrate and be coupled to the grid coupling portion 764.

[0585] At this time, the shape of the grid 720 coupled to the grid coupling portion 764 can be different from the shape of the other grids 720 not coupled to the grid coupling portion 764.

[0586] As one example, the length of the grid 720 coupled to the grid coupling portion 764, i.e., the length in the up-down direction, can be smaller than the length of the other grids 720 not coupled to the grid coupling portion 764.

[0587] In addition, the width of the end portions of the grid 720 coupled to the grid coupling portion 764, i.e., the length in the left-right direction, can be smaller than the width of the end portions of the other grids 720 not coupled to the grid coupling portion 764.

[0588] At this time, the width of the portion of the grid 720 combined with the grid combination portion 764, which is combined with the support plate 710, can be the same as the width of the portion of the other grid 720, which is not combined with the grid combination portion 764, which is combined with the support plate 710.

[0589] That is, in the case where the shape of the grid 720 combined with the magnet housing 760 is the same as the shape of the other grid 720 not combined with the magnet housing 760, a large change in the structure of the arc extinguishing portion 700 is required in order to provide the magnet housing 760.

[0590] Therefore, the arc extinguishing portion 700 of the present embodiment can minimize the change in the structure of the arc extinguishing portion 700 by changing the shape of the portion of the grid 720 combined with the magnet housing 760.

[0591] The step formed inside the grid combination portion 764 can be determined according to the shape of the lower end portion of the grid 720 inserted and combined with the grid combination portion 764.

[0592] The grid combination portion 764 can be provided in plural. The plural grid combination portions 764 can be spaced apart from each other.

[0593] In the illustrated embodiment, the grid combination portion 764 is formed in two, including a first grid combination portion 764a located in the direction toward the fixed contact 311, i.e., the front side, and a second grid combination portion 764b located in the direction toward the arc flow passage 750, i.e., the rear side.

[0594] Each of the grid combination portions 764a, 764b is spaced apart from each other in the front-rear direction on the side of the magnet housing 760 toward the grid 720, i.e., the upper side in the illustrated embodiment.

[0595] In each of the grid combination portions 764, the lower side of the grid 720 different from each other can be inserted. In the illustrated embodiment, the first grid combination portion 764a located in the front side has the grid 720 disposed in the fifth from the front side inserted and combined therewith. In addition, the second grid combination portion 764b located in the rear side has the grid 720 disposed adjacent to the rear side of the grid 720 inserted and combined therewith.

[0596] It can be understood that the grid 720 inserted and combined into the second grid combination portion 764b is the grid 720 disposed in the sixth from the front side.

[0597] The arc inflow portion 765 forms a passage for the arc flowing in the arc extinguishing portion 700 to flow toward the grid 720.

[0598] Specifically, the path A.P of the arc is formed by the main magnetic field M.M.F and the sub magnetic field S.M.F formed by the arc extinguishing magnet portion 770 housed in the magnet housing 760. Thus, the path A.P of the arc flows toward the grid 720.

[0599] At this time, the width direction of the grid 720, in the illustrated embodiment, the right side direction and the left side direction, each end portion is in a pointed shape. Thus, the flowing arc can travel toward both side end portions of the grid 720.

[0600] However, as described above, the magnet housing 760 is inserted into a portion of the plurality of grids 720. Thus, the flowing arc can travel toward both side end portions of the grid 720 into which the magnet housing 760 is inserted.

[0601] Here, the arc inflow portion 765 functions as a passage that enables the inflowing arc to flow toward another grid 720 adjacent to the grid 720 into which the magnet housing 760 is inserted.

[0602] That is, in the illustrated embodiment, the arc inflow portion 765 can guide the inflowing arc to flow toward another grid 720 adjacent to the front side or the rear side of the grid 720 into which the magnet housing 760 is inserted.

[0603] The arc inflow portion 765 is recessed on the side of the magnet housing 760 toward the fixed contact 311, in the illustrated embodiment, the lower side. In one embodiment, the arc inflow portion 765 can be recessed on one face passing through the lower side end portion of the first housing portion 761.

[0604] The arc inflow portion 765 can extend a prescribed length. In the illustrated embodiment, the arc inflow portion 765 includes a first portion extending obliquely toward the upper side, and a second portion communicating with the first portion, extending vertically toward the upper side.

[0605] The extension length of the arc inflow portion 765 can be formed to be sufficient for the flowing arc to flow toward the adjacent grid 720.

[0606] The arc inflow portion 765 can be formed in a plurality. The plurality of arc inflow portions 765 can be arranged on both sides of the first housing portion 761. In one embodiment, the plurality of arc inflow portions 765 can be arranged so as to surround both sides of the first housing portion 761.

[0607] In the illustrated embodiment, the arc inflow portion 765 is formed so as to surround the first housing portion 761 in both directions in which the magnet housing 760 extends, that is, on the right side and the left side.

[0608] Thus, the arc flowing toward the grid 720 into which the magnet housing 760 is incorporated among the plurality of grids 720 can flow toward the adjacent grid 720 through the arc inflow portion 765.

[0609] Thus, the generated arc can be effectively extinguished and pass through the arc extinguishing portion 700.

[0610] The arc extinguishing magnet portion 770 forms a magnetic field for forming the arc path A.P. The arc flowing inside the magnetic field formed by the arc extinguishing magnet portion 770 is subjected to electromagnetic force defined by Lorentz force. Thus, the arc path A.P. is formed so that the generated arc travels in a prescribed direction.

[0611] The arc extinguishing magnet portion 770 is accommodated in the magnet housing 760. That is, the arc extinguishing magnet portion 770 is not exposed to the outside. Thus, the arc extinguishing magnet portion 770 is not damaged by the generated arc and dust or the like included in the arc.

[0612] The arc extinguishing magnet portion 770 can be provided in any form capable of forming a magnetic field. In an embodiment, the arc extinguishing magnet portion 770 can be a permanent magnet or an electromagnet.

[0613] The arc extinguishing magnet portion 770 can be provided in plural. The plural arc extinguishing magnet portions 770 can form a main magnetic field M.M.F. as the magnetic field formed between each other. In addition, the plural arc extinguishing magnet portions 770 can form a secondary magnetic field S.M.F. as the magnetic field formed by each of the arc extinguishing magnet portions 770.

[0614] In the illustrated embodiment, the arc extinguishing magnet portion 770 is provided with three, including a first arc extinguishing magnet 771, a second arc extinguishing magnet 772, and a third arc extinguishing magnet 773. The number of the arc extinguishing magnet portion 770 can be changed.

[0615] The first arc extinguishing magnet 771 forms a magnetic field for forming the arc path A.P.

[0616] The first arc extinguishing magnet 771 itself can form the secondary magnetic field S.M.F. In addition, the first arc extinguishing magnet 771 can form the main magnetic field M.M.F. together with the second arc extinguishing magnet 772 and the third arc extinguishing magnet 773.

[0617] The first arc extinguishing magnet 771 can be in a prescribed shape. In the illustrated embodiment, the first arc extinguishing magnet 771 is formed in a rectangular cross section having a length in the left-right direction greater than a length in the up-down direction.

[0618] The first arc extinguishing magnet 771 can be in any shape accommodated in the first accommodation groove 761a and capable of being closed by the cover portion 761d. That is, the shape of the first arc extinguishing magnet 771 can be determined in accordance with the shape of the first accommodation groove 761a.

[0619] Thus, the first arc extinguishing magnet 771 is not exposed to the outside. As a result, the first arc extinguishing magnet 771 is not damaged by the generated arc.

[0620] The first arc extinguishing magnet 771 includes a first face 771a and a second face 771b.

[0621] The first face 771a forms a side of the first arc extinguishing magnet 771 facing the grid 720. In other words, the first face 771a forms a side of the first arc extinguishing magnet 771 opposite the fixed contact 311. In the illustrated embodiment, the first face 771a can be defined by an upper side of the first arc extinguishing magnet 771.

[0622] The second face 771b forms another side of the first arc extinguishing magnet 771 facing the fixed contact 311. In other words, the second face 771b forms another side of the first arc extinguishing magnet 771 opposite the grid 720. In the illustrated embodiment, the second face 771b can be defined by a lower side of the first arc extinguishing magnet 771.

[0623] The first face 771a and the second face 771b are configured to face each other. That is, the first face 771a and the second face 771b are a side and another side of the first arc extinguishing magnet 771 facing each other.

[0624] The first face 771a can be magnetized to either one of N-pole or S-pole. Also, the second face 771b can be magnetized to the other one of N-pole or S-pole. That is, the first face 771a and the second face 771b are magnetized to opposite polarities to each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 771a and the second face 771b.

[0625] The second arc extinguishing magnet 772 forms a magnetic field for forming the arc path A.P.

[0626] The second arc extinguishing magnet 772 can form the secondary magnetic field S.M.F. by itself. Also, the second arc extinguishing magnet 772 can form the main magnetic field M.M.F. together with the first arc extinguishing magnet 771 and the third arc extinguishing magnet 773.

[0627] The second arc extinguishing magnet 772 can have a prescribed shape. In the illustrated embodiment, the second arc extinguishing magnet 772 is formed in a rectangular cross-section having a length in the front-rear direction greater than a length in the up-down direction.

[0628] The second arc extinguishing magnet 772 can be any shape that is accommodated in the second accommodation groove 762a and can be sealed by the support plate 710. That is, the shape of the second arc extinguishing magnet 772 can be determined according to the shape of the second accommodation groove 762a.

[0629] Thereby, the second arc extinguishing magnet 772 does not protrude to the outside. As a result, the second arc extinguishing magnet 772 is not damaged by the generated arc.

[0630] The second arc extinguishing magnet 772 includes a first face 772a and a second face 772b.

[0631] The first face 772a forms a side of the second arc extinguishing magnet 772 facing the support plate 710. In other words, the first face 772a forms a side of the second arc extinguishing magnet 772 opposite the grid 720. In the illustrated embodiment, the first face 772a can be defined by a left side or an outer side of the second arc extinguishing magnet 772.

[0632] The second face 772b forms another side of the second arc extinguishing magnet 772 facing the grid 720. In other words, the second face 772b forms another side of the second arc extinguishing magnet 772 opposite the support plate 710. In the illustrated embodiment, the second face 772b can be defined by a right side or an inner side of the second arc extinguishing magnet 772.

[0633] The first face 772a and the second face 772b are configured to face each other. In other words, the first face 772a and the second face 772b are a side and another side of the second arc extinguishing magnet 772 facing each other.

[0634] The first face 772a can be magnetized to either one of N-pole or S-pole. Also, the second face 772b can be magnetized to the other one of N-pole or S-pole. That is, the first face 772a and the second face 772b are magnetized to opposite polarities from each other. Thereby, a secondary magnetic field S.M.F. can be formed between the first face 772a and the second face 772b.

[0635] The third arc extinguishing magnet 773 forms a magnetic field for forming the arc path A.P.

[0636] The third arc extinguishing magnet 773 itself can form a secondary magnetic field S.M.F. Also, the third arc extinguishing magnet 773 can form a main magnetic field M.M.F. together with the first arc extinguishing magnet 771 and the second arc extinguishing magnet 772.

[0637] The third arc extinguishing magnet 773 can be provided in any form capable of forming a magnetic field. In one embodiment, the third arc extinguishing magnet 773 can be a permanent magnet or an electromagnet.

[0638] The third arc extinguishing magnet 773 can have a prescribed shape. In the illustrated embodiment, the third arc extinguishing magnet 773 is formed in a rectangular cross-section having a length in the left-right direction greater than a length in the up-down direction.

[0639] The third arc extinguishing magnet 773 can be any shape accommodated in the third accommodation groove 763a and capable of being sealed by the support plate 710. That is, the shape of the third arc extinguishing magnet 773 can be determined according to the shape of the third accommodation groove 763a.

[0640] The third arc extinguishing magnet 773 includes a first face 773a and a second face 773b.

[0641] The first face 773a forms a side of the third arc extinguishing magnet 773 facing the support plate 710. In other words, the first face 773a forms a side of the third arc extinguishing magnet 773 opposite the grid 720. In the illustrated embodiment, the first face 773a can be defined by a right side or an outer side of the third arc extinguishing magnet 773.

[0642] The second face 773b forms another side of the third arc extinguishing magnet 773 facing the grid 720. In other words, the second face 773b forms another side of the third arc extinguishing magnet 773 opposite the support plate 710. In the illustrated embodiment, the second face 773b can be defined by a left side or an inner side of the third arc extinguishing magnet 773.

[0643] The first face 773a and the second face 773b are configured to face each other. In other words, the first face 773a and the second face 773b are a side and another side of the third arc extinguishing magnet 773 facing each other.

[0644] In addition, the second face 773b is configured to face the second face 772b of the second arc extinguishing magnet 772.

[0645] The first face 773a can be magnetized to either one of N-pole or S-pole. In addition, the second face 773b can be magnetized to the other one of N-pole or S-pole. That is, the first face 773a and the second face 773b are magnetized to be in opposite polarities to each other. Thereby, a secondary magnetic field S.M.F can be formed between the first face 773a and the second face 773b.

[0646] Detailed explanation about the process of forming the primary magnetic field M.M.F and the secondary magnetic field S.M.F by the respective arc extinguishing magnets 771, 772, 773 will be made later.

[0647] Figures 31 to 44

[0648] As described above, the air circuit breaker 10 of the embodiment of the present application includes the fixed contact 311 and the movable contact 321. If the fixed contact 311 and the movable contact 321 are separated, an arc is generated due to the current in the energization.

[0649] The air circuit breaker 10 of the embodiment of the present application includes various constituent elements for forming an arc path A.P for the generated arc to flow toward the arc extinguishing portion 600, 700.

[0650] Hereinafter, the process of forming the arc path A.P in the air circuit breaker 10 of the embodiment of the present application will be explained in detail with reference to (1) Explanation of the process of the path A.P of the electric arc formed by the cover magnet portion 400 according to the embodiment of the present application , the process of forming the arc path A.P in the air circuit breaker 10 of the embodiment of the present application will be explained in detail with reference to

[0651] The various embodiments described below can independently form the arc path A.P, or can form the arc path A.P by combining two or more of the embodiments with each other.

[0652] In the following description, the portions marked with "0" indicate that the current flows out from the paper. In addition, the portions marked with "0" indicate that the current flows into the paper.

[0653] It will be understood that the portions marked with the above marks are portions in which the air circuit breaker 10 is energized with an external power source or load due to the contact of the fixed contact 311 and the movable contact 321.

[0654] Figures 31 to 32

[0655] Referring to Figure 31 , the process of forming the arc path A.P by the cover magnet portion 400 of the embodiment of the present application will be described in detail.

[0656] Referring to Figure 32 , the front surface of the air circuit breaker 10 including the cover magnet portion 400 of the embodiment of the present application is shown. In addition, referring to Figure 31 , the top surface of the air circuit breaker 10 including the cover magnet portion 400 of the embodiment of the present application is shown.

[0657] For convenience of understanding, the upper cover 110 is omitted.

[0658] In the illustrated embodiment, the first to fourth cover magnets 410, 420, 430, 440 of the cover magnet portion 400 are positioned to have the respective fixed contacts 310 positioned therebetween.

[0659] At this time, the respective upper surfaces, i.e., the respective first surfaces 411, 421, 431, 441, of the respective cover magnets 410, 420, 430, 440 are formed to be S poles. In addition, the respective lower surfaces, i.e., the respective second surfaces 412, 422, 432, 442, of the respective cover magnets 410, 420, 430, 440 are formed to be N poles.

[0660] The respective cover magnets 410, 420, 430, 440 form a secondary magnetic field S.M.F as the magnetic field formed by themselves.

[0661] Although not shown, the respective cover magnets 410, 420, 430, 440 positioned adjacent to each other can form a primary magnetic field M.M.F with each other.

[0662] In Figure 31 ​In (a) of FIG. 10, the direction of the current flowing in each breaking portion 300 is from the direction in which the paper flows out, that is, the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0663] Further, the direction of the secondary magnetic field S.M.F formed by each cover magnet 410, 420, 430, 440 is from each second surface 412, 422, 432, 442 toward each first surface 411, 421, 431, 441, that is, in the illustrated embodiment, from the lower side toward the upper side.

[0664] When the Ampere's left-hand rule is used at the position where each fixed contact 311 and each movable contact 321 are in contact, the path A.P of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in the direction of the side edge of the arc extinguishing portion 600, 700, in the illustrated embodiment, the left side of the upper side, is formed.

[0665] Therefore, in the illustrated embodiment of (a) of FIG. 10, the generated arc travels toward the side (that is, the left side) edge of the grid 620, 720. Thereby, the generated arc can flow rapidly and be extinguished. Figure 31

[0666] In (b) of FIG. 10, the direction of the current flowing in each breaking portion 300 is toward the direction in which the paper flows in, that is, the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through the fixed contact 310. Figure 31 Further, the direction of the secondary magnetic field S.M.F formed by each cover magnet 410, 420, 430, 440 is from each second surface 412, 422, 432, 442 toward each first surface 411, 421, 431, 441, that is, in the illustrated embodiment, from the lower side toward the upper side.

[0667] When the Ampere's left-hand rule is used at the position where each fixed contact 311 and each movable contact 321 are in contact, the path A.P of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in the direction of the side edge of the arc extinguishing portion 600, 700, in the illustrated embodiment, the right side of the upper side, is formed.

[0668] Therefore, in the illustrated embodiment of (b) of FIG. 10, the generated arc travels toward the other side (that is, the right side) edge of the grid 620, 720. Thereby, the generated arc can flow rapidly and be extinguished.

[0669] Figure 32 Referring to FIG. 11, a plan view of an example shown in FIG. 10 is shown.

[0670] Referring to FIG. 12, a plan view of an example shown in FIG. 10 is shown. Figure 31 Figure 32 Referring to FIG. 13, a plan view of an example shown in FIG. 10 is shown. ​​​

[0671] In Figure 31 (a) of FIG. 10, the direction of the current flowing in each breaking portion 300 is the direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310. It is understood that the direction of the current is the same as the embodiment shown in (a) of FIG. 9. Figure 32

[0672] As described above, the direction of the secondary magnetic field S.M.F formed by each cover magnet 410, 420, 430, 440 is formed in a direction from each second surface 412, 422, 432, 442 toward each first surface 411, 421, 431, 441, i.e., in a direction toward the arc extinguishing portion 600, 700.

[0673] When the Ampere's left-hand rule is used at the position where each fixed contact 311 and each movable contact 321 are in contact, the path A.P of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in a direction along the side edge of the arc extinguishing portion 600, 700, i.e., in a direction along the left side of the upper side in the illustrated embodiment.

[0674] Therefore, in the embodiment shown in (a) of FIG. 10, the generated arc travels toward the side (i.e., the left side) edge of the grid 620, 720. Thereby, the generated arc can be quickly moved and extinguished. Figure 32

[0675] In Figure 31 (b) of FIG. 11, the direction of the current flowing in each breaking portion 300 is the direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through the fixed contact 310. It is understood that the direction of the current is the same as the embodiment shown in (b) of FIG. 9. Figure 32

[0676] As described above, the direction of the secondary magnetic field S.M.F formed by each cover magnet 410, 420, 430, 440 is formed in a direction from each second surface 412, 422, 432, 442 toward each first surface 411, 421, 431, 441, i.e., in a direction toward the arc extinguishing portion 600, 700.

[0677] When the Ampere's left-hand rule is used at the position where each fixed contact 311 and each movable contact 321 are in contact, the path A.P of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in a direction along the side edge of the arc extinguishing portion 600, 700, i.e., in a direction along the right side of the upper side in the illustrated embodiment.

[0678] Therefore, in the embodiment shown in (a) of FIG. 10, the generated arc travels toward the side (i.e., the left side) edge of the grid 620, 720. Thereby, the generated arc can be quickly moved and extinguished. (2) Explanation of the process of the path A.P of the electric arc formed by the arc extinguishing portion 600 according to the embodiment of the present application ​​​In the embodiment shown in (b), the generated arc travels toward the other side (i.e., the right side) edge of the grid 620, 720. Thereby, the generated arc can quickly move and be extinguished.

[0679] In the present embodiment, the respective first faces 411, 421, 431, 441 of the respective cover magnets 410, 420, 430, 440 can be magnetized to the same polarity as each other (i.e., S-pole). Likewise, the respective second faces 412, 422, 432, 442 of the respective cover magnets 410, 420, 430, 440 can be magnetized to the same polarity as each other (i.e., N-pole).

[0680] In the present embodiment, even if the direction of the current flowing through the respective contacts 311, 321 changes, the path A.P of the arc is formed toward the end portion of the grid 620, 720 and the grid cover 630, 730.

[0681] Therefore, the generated arc can quickly move and be extinguished along the path A.P of the arc regardless of the direction of the energized current.

[0682] Figures 33 to 36

[0683] Referring to Figure 33 , the process of forming the path A.P of the arc by the arc extinguishing portion 600 of an embodiment of the present application is explained in detail.

[0684] In the illustrated embodiment, for ease of understanding, any one of the plurality of arc extinguishing portions 600 is shown. It is understood that the path A.P of the arc is formed in the other arc extinguishing portions 600 not shown in accordance with the following explanation.

[0685] Referring to Figure 34 , the front surface of the arc extinguishing portion 600 of an embodiment of the present application is shown. In addition, referring to Figure 33 , the side cross-sectional view of the arc extinguishing portion 600 of an embodiment of the present application is shown.

[0686] As previously described, the arc extinguishing portion 600 of the present embodiment includes the arc extinguishing magnet 634 housed in the cover main body 631.

[0687] The first face 634a of the arc extinguishing magnet 634, i.e., the face on the side opposite the grid 620, is magnetized to the S-pole. Thereby, the second face 634b of the arc extinguishing magnet 634, i.e., the face toward the other side of the grid 620, is magnetized to the N-pole.

[0688] The arc extinguishing magnet 634 forms a secondary magnetic field S.M.F as the magnetic field formed by itself. The secondary magnetic field S.M.F formed by the arc extinguishing magnet 634 is in the direction toward the grid 620, i.e., in the illustrated embodiment, the direction from the upper side toward the lower side.

[0689] In Figure 33 (a) of FIG. 6, the direction of the current flowing in each contact 311, 321 is a direction flowing out of the paper, i.e., a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0690] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 is contacted, the path A.P. of the arc can be expected. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in each contact 311, 321 is formed in a direction toward the one side edge of the grid 620, i.e., the right side of the upper side in the illustrated embodiment.

[0691] In Figure 34 (b) of FIG. 6, the direction of the current flowing in each contact 311, 321 is a direction flowing into the paper, i.e., a direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321.

[0692] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 is contacted, the path A.P. of the arc can be expected. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing in each contact 311, 321 is formed in a direction toward the other side edge of the grid 620, i.e., the left side of the upper side in the illustrated embodiment.

[0693] As described above, the end portions of the grid 620 in the left-right direction can be in a pointed shape. Thereby, the arc can flow along the formed path A.P. of the arc and enter the end portions of the grid 620.

[0694] Further, the path A.P. of the arc is formed toward the grid cover 630 located at the upper side of the grid 620. In the grid cover 630, a through-hole portion 632a of an upper frame 632 which communicates with the outside, a mesh portion 633, and a through-hole 636a of a barrier plate 636 are provided.

[0695] Therefore, the generated arc can rapidly move along the formed path A.P. of the arc and be extinguished, and be discharged to the outside.

[0696] In Figure 34 (a) of FIG. 6, the direction of the current flowing in each contact 311, 321 is a direction flowing out of the paper, i.e., a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310. Figure 33 (a) of FIG. 6 (refer to solid arrows of (a) of FIG. 6).

[0697] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the electric arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field SMF and the current flowing at each contact 311 and 321 is formed in the direction of entering the paper, i.e., towards the left side of the grid 620.

[0698] Although not illustrated, it is understandable, such as Figure 34 In the embodiment shown in (a), the path AP of the electric arc is formed toward the grille cover 630 located on the upper side of the grille 620.

[0699] exist Figure 34 In (b), the current flowing through each contact 311, 321 is directed toward the arc-extinguishing section 600, that is, the current flowing from the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321 (see reference). Figure 33 The direction of the solid arrow in (b).

[0700] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the electric arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field SMF and the current flowing at each contact 311 and 321 is formed in the direction from the paper, i.e., towards the right side of the grid 620.

[0701] Although not illustrated, it can be understood that in this embodiment, as... Figure 35 In the embodiment shown in (b), the path AP of the electric arc is formed toward the grid cover 630 located on the upper side of the grid 620.

[0702] As described above, the left and right ends of the grid 620 can be pointed. Therefore, the electric arc can flow along the path AP of the formed arc and enter the ends of the grid 620.

[0703] Therefore, the generated electric arc can move rapidly along the path AP of the formed arc and be extinguished, discharged to the outside.

[0704] Reference Figure 36 The front view of an arc-extinguishing part 600 according to an embodiment of the present invention is shown. Additionally, refer to... Figure 35 The image shows a side cross-section of the arc-extinguishing part 600 according to an embodiment of the present invention.

[0705] As described above, the arc-extinguishing part 600 of this embodiment includes an arc-extinguishing magnet 634 housed in the cover body 631.

[0706] The first face 634a of the arc extinguishing magnet 634, i.e., the face on the side opposite to the grid 620, is magnetized as an N pole. Thus, the second face 634b of the arc extinguishing magnet 634, i.e., the face on the other side toward the grid 620, is magnetized as an S pole.

[0707] The arc extinguishing magnet 634 forms a secondary magnetic field S.M.F. as its own formed magnetic field. The secondary magnetic field S.M.F. formed by the arc extinguishing magnet 634 is in a direction away from the grid 620, i.e., in the direction from the lower side to the upper side in the illustrated embodiment.

[0708] In (a) of FIG. 20, Figure 35 the current flowing in the respective contacts 311, 321 is in a direction from the paper, i.e., in a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0709] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F. and the current flowing in the respective contacts 311, 321 is formed in a direction along the left side toward the one side edge of the grid 620, i.e., the upper side in the illustrated embodiment.

[0710] In (b) of FIG. 20, Figure 36 the current flowing in the respective contacts 311, 321 is in a direction toward the paper, i.e., in a direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through the respective contacts 311, 321.

[0711] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F. and the current flowing in the respective contacts 311, 321 is formed in a direction along the right side toward the other side edge of the grid 620, i.e., the upper side in the illustrated embodiment.

[0712] In (a) of FIG. 21, Figure 36 the current flowing in the respective contacts 311, 321 is in a direction away from the arc extinguishing portion 600, i.e., in a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310 (see the solid arrow in (a) of FIG. 20). Figure 35

[0713] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F. and the current flowing in the respective contacts 311, 321 is formed in a direction from the paper, i.e., in a direction toward the right side of the grid 620.

[0714] Although not illustrated, it is understood that, as in​Figure 36 In the embodiment shown in (a) of FIG. 6, the path A.P of the arc is formed toward the grid cover 630 located on the upper side of the grid 620.

[0715] In Figure 36 In (b) of FIG. 6, the current flowing through the respective contacts 311, 321 is in the direction toward the arc extinguishing portion 600, i.e., the direction in which the current flowing from the external power source or load is transmitted to the air circuit breaker 10 through the respective contacts 311, 321 (refer to the solid arrow in (b) of FIG. 6). Figure 33

[0716] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are in contact, the path A.P of the arc can be anticipated. That is, the electromagnetic force formed by the secondary magnetic field S.M.F and the current flowing through the respective contacts 311, 321 is formed in the direction into the paper, i.e., in the direction toward the left side of the grid 620.

[0717] Although not shown, it is understood that, in the embodiment shown in (b) of FIG. 6, the path A.P of the arc is formed toward the grid cover 630 located on the upper side of the grid 620. (3) Explanation of the process of the path A.P of the electric arc formed by the CT magnet portion 500 according to the embodiment of the present application and the arc extinguishing portion 600 according to the embodiment of the present application

[0718] As described above, the end portions of the grid 620 in the left-right direction can be in a pointed shape. Thereby, the arc can flow along the formed path A.P of the arc and enter the end portions of the grid 620.

[0719] Further, the path A.P of the arc is formed toward the grid cover 630 located on the upper side of the grid 620. The through-hole portion 632a of the upper frame 632, the mesh portion 633, and the through-hole 636a of the barrier plate 636 are provided in the grid cover 630.

[0720] Therefore, the generated arc can rapidly move along the formed path A.P of the arc and be extinguished, and be discharged to the outside.

[0721] In the present embodiment, even if the polarity of the arc extinguishing magnet 634 is changed, the path A.P of the arc formed is in the width direction of the grid 620, i.e., the left-right direction in the illustrated embodiment. Further, the path A.P of the arc formed is toward the grid cover 630 located at the position opposite to the respective contacts 311, 321.

[0722] Still further, even in the case where the direction of the current flowing through the respective contacts 311, 321 is changed, the path A.P of the arc is formed toward the end portions of the grid 620 and the grid cover 630.

[0723] ​​Therefore, even if the polarity of the arc extinguishing magnet 634 and the direction of the flowing current are changed, the generated arc can be rapidly moved along the arc path A.P and extinguished.

[0724] Figures 37 to 40 Figure 37

[0725] Referring to Figure 38 , the process in which the arc path A.P is formed by the CT magnet portion 500 of an embodiment of the present application and the arc extinguishing portion 600 of an embodiment will be described in detail.

[0726] As described above, the CT magnet portion 500 of an embodiment of the present application includes the CT magnet 530.

[0727] The CT magnet 530 is accommodated in the space portion 520 of the housing 510 and forms the secondary magnetic field S.M.F. In addition, the CT magnet 530 can form the main magnetic field M.M.F. together with the arc extinguishing magnet 634 of the arc extinguishing portion 600.

[0728] In addition, as described above, the arc extinguishing portion 600 of an embodiment of the present application includes the arc extinguishing magnet 634.

[0729] The arc extinguishing magnet 634 is accommodated in the inside of the grid cover 630 and forms the secondary magnetic field S.M.F. In addition, the arc extinguishing magnet 634 can form the main magnetic field M.M.F. together with the CT magnet 530 of the CT magnet portion 500.

[0730] At this time, the mutually facing surfaces of the CT magnet 530 and the arc extinguishing magnet 634, i.e., the first surface 531 of the CT magnet 530 and the second surface 634b of the arc extinguishing magnet 634, can be magnetized to different polarities from each other.

[0731] Referring to Figure 37 , the front surface of the air circuit breaker 10 including the CT magnet portion 500 of an embodiment of the present application and the arc extinguishing portion 600 of an embodiment is shown. In addition, referring to Figure 37 , the right side surface of the air circuit breaker 10 including the CT magnet portion 500 of an embodiment of the present application and the arc extinguishing portion 600 of an embodiment is shown.

[0732] The first surface 531 of the CT magnet 530, i.e., the surface facing one side of each contact 311, 321 or the arc extinguishing portion 600, is magnetized to the S pole. Thus, the second surface 532 of the CT magnet 530, i.e., the surface facing the other side opposite to each contact 311, 321 or the arc extinguishing portion 600, is magnetized to the N pole. The CT magnet 530 forms the secondary magnetic field S.M.F. as a magnetic field formed by itself.

[0733] Furthermore, the first surface 634a of the arc-extinguishing magnet 634, that is, the surface opposite to each contact 311, 321 or the CT magnet section 500, is magnetized as the S pole. Consequently, the second surface 634b of the arc-extinguishing magnet 634, that is, the surface facing the other contact 311, 321 or the CT magnet section 500, is magnetized as the N pole. The arc-extinguishing magnet 634 forms a secondary magnetic field SMF as a magnetic field generated by itself.

[0734] Furthermore, a main magnetic field MMF is formed between the CT magnet 530 and the arc-extinguishing magnet 634. Specifically, the main magnetic field MMF is formed in the direction from the second surface 634b of the arc-extinguishing magnet 634 toward the first surface 531 of the CT magnet 530, which in the illustrated embodiment is from the top to the bottom.

[0735] exist Figure 38 In (a), the current flowing at each contact 311, 321 is in the direction of the paper flowing out, that is, the direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0736] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the arc can be anticipated.

[0737] That is, the electromagnetic force formed by the main magnetic field MMF formed between the CT magnet 530 and the arc-extinguishing magnet 634 and the current flowing at each contact 311, 321 is formed along one side edge toward the grille 620, which is the upper right side in the illustrated embodiment.

[0738] exist Figure 38 In (b), the current flowing through each contact 311, 321 is in the direction of entering the paper, that is, the direction in which the current flowing through the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321.

[0739] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the arc can be anticipated.

[0740] That is, the electromagnetic force formed by the main magnetic field MMF formed between the CT magnet 530 and the arc-extinguishing magnet 634 and the current flowing at each contact 311, 321 is formed along one side edge toward the grille 620, which is the upper left side in the illustrated embodiment.

[0741] exist Figure 37 In (a), the current flowing through each contact 311, 321 is in the direction away from the arc-extinguishing section 600, that is, the direction in which the current flowing in the air circuit breaker 10 is transferred to the external power source or load through each contact 311, 321 (refer to...). Figure 38(The solid arrow in (a)).

[0742] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the arc can be anticipated.

[0743] That is, the electromagnetic force formed by the main magnetic field MMF formed between the CT magnet 530 and the arc-extinguishing magnet 634 and the current flowing at each contact 311, 321 is formed in the direction from the paper, that is, in the direction to the right of the grid 620.

[0744] Although not illustrated, it is understandable, such as Figure 38 In the embodiment shown in (a), the path AP of the electric arc is formed toward the grille cover 630 located on the upper side of the grille 620.

[0745] exist Figure 37 In (b), the current flowing through each contact 311, 321 is in the direction towards the arc-extinguishing section 600, that is, the direction in which the current flowing from the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321 (refer to...). Figure 39 (The solid arrow in (b)).

[0746] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the arc can be anticipated.

[0747] That is, the electromagnetic force formed by the main magnetic field MMF formed between the CT magnet 530 and the arc-extinguishing magnet 634 and the current flowing at each contact 311, 321 is formed along the direction of entering the paper, that is, towards the left side of the grid 620.

[0748] Although not illustrated, it is understandable, such as Figure 40 In the embodiment shown in (b), the path AP of the electric arc is formed toward the grid cover 630 located on the upper side of the grid 620.

[0749] As described above, the left and right ends of the grid 620 can be pointed. Therefore, the electric arc can flow along the path AP of the formed arc and enter the ends of the grid 620.

[0750] Furthermore, the path AP of the electric arc is formed toward the grid cover 630 located on the upper side of the grid 620. The grid cover 630 is provided with a through hole 632a of the upper frame 632 that communicates with the outside, a mesh portion 633, and a through hole 636a of the barrier plate 636.

[0751] Therefore, the generated electric arc can move rapidly along the path AP of the formed arc and be extinguished, discharged to the outside.

[0752] Referring to Figure 39 , a front surface of the air circuit breaker 10 including the CT magnet portion 500 and an embodiment of the arc extinguishing portion 600 is shown. Also, referring to Figure 39 , a side surface of the air circuit breaker 10 including the CT magnet portion 500 and an embodiment of the arc extinguishing portion 600 is shown.

[0753] The first surface 531 of the CT magnet 530, i.e., the surface of one side toward the respective contact 311, 321 or the arc extinguishing portion 600 is magnetized as an N pole. Thus, the second surface 532 of the CT magnet 530, i.e., the surface of the other side opposite to the respective contact 311, 321 or the arc extinguishing portion 600 is magnetized as an S pole. The CT magnet 530 forms a secondary magnetic field S.M.F. as a magnetic field formed by itself.

[0754] Also, the first surface 634a of the arc extinguishing magnet 634, i.e., the surface of one side opposite to the respective contact 311, 321 or the CT magnet portion 500 is magnetized as an N pole. Thus, the second surface 634b of the arc extinguishing magnet 634, i.e., the surface of the other side toward the respective contact 311, 321 or the CT magnet portion 500 is magnetized as an S pole. The arc extinguishing magnet 634 forms a secondary magnetic field S.M.F. as a magnetic field formed by itself.

[0755] Further, a primary magnetic field M.M.F. is formed between the CT magnet 530 and the arc extinguishing magnet 634. Specifically, the primary magnetic field M.M.F. is formed in a direction from the first surface 531 of the CT magnet 530 toward the second surface 634b of the arc extinguishing magnet 634, i.e., in a direction from the lower side toward the upper side in the illustrated embodiment.

[0756] In (a) of Figure 40 , the current flowing in the respective contact 311, 321 is in a direction from the paper, i.e., in a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0757] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated.

[0758] That is, the electromagnetic force formed by the primary magnetic field M.M.F. formed between the CT magnet 530 and the arc extinguishing magnet 634 and the current flowing in the respective contacts 311, 321 is formed in a direction toward the left side of the one side edge of the grid 620, i.e., the upper side in the illustrated embodiment.

[0759] In (b) of Figure 40 , the current flowing in the respective contact 311, 321 is in a direction into the paper, i.e., in a direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through the respective contact 311, 321.

[0760] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated.

[0761] That is, the electromagnetic force formed by the main magnetic field M.M.F formed between the CT magnet 530 and the arc extinguishing magnet 634 and the current flowing through the respective contacts 311, 321 is formed in the direction toward the side edge of the grid 620, the right side in the illustrated embodiment.

[0762] In (a) of FIG. 13, Figure 39 the current flowing through the respective contacts 311, 321 is in the direction away from the arc extinguishing portion 600, that is, the direction in which the current flowing through the air circuit breaker 10 is transferred to the external power source or load through the respective contacts 311, 321 (refer to the solid arrow in (a) of FIG. 13). Figure 40

[0763] Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated.

[0764] That is, the electromagnetic force formed by the main magnetic field M.M.F formed between the CT magnet 530 and the arc extinguishing magnet 634 and the current flowing through the respective contacts 311, 321 is formed in the direction into the paper, that is, the direction toward the left side of the grid 620.

[0765] Although not illustrated, it can be understood that, as in the embodiment shown in (a) of FIG. 13, in the present embodiment, the path A.P. of the arc is formed toward the grid cover 630 located at the upper side of the grid 620. Figure 40

[0766] In (b) of FIG. 13, Figure 39 the current flowing through the respective contacts 311, 321 is in the direction toward the arc extinguishing portion 600, that is, the direction in which the current flowing through the external power source or load is transferred to the air circuit breaker 10 through the respective contacts 311, 321 (refer to the solid arrow in (b) of FIG. 13). (4) Explanation of the process of the path A.P of the electric arc formed by the arc extinguishing portion 700 according to another embodiment of the present application Here, when the Ampere's left-hand rule is used at the position where the respective contacts 311, 321 are contacted, the path A.P. of the arc can be anticipated.

[0767] That is, the electromagnetic force formed by the main magnetic field M.M.F formed between the CT magnet 530 and the arc extinguishing magnet 634 and the current flowing through the respective contacts 311, 321 is formed in the direction out of the paper, that is, the direction toward the right side of the grid 620.

[0768] Although not illustrated, it can be understood that, as in the embodiment shown in (b) of FIG. 13, in the present embodiment, the path A.P. of the arc is formed toward the grid cover 630 located at the upper side of the grid 620.

[0769] Figures 41 to 44 ​​​In the embodiment shown in (b), in this embodiment, the arc path A.P is formed so as to be directed toward the grid cover 630 located on the upper side of the grid 620.

[0770] As described above, the end portions of the grid 620 in the left-right direction can be in a pointed shape. By this, the arc can flow along the formed arc path A.P and enter toward the end portions of the grid 620.

[0771] Further, the arc path A.P is formed so as to be directed toward the grid cover 630 located on the upper side of the grid 620. In the grid cover 630, a through-hole portion 632a of an upper frame 632 which communicates with the outside, a mesh portion 633, and a through-hole 636a of a barrier plate 636 are provided.

[0772] Therefore, the generated arc can rapidly move along the formed arc path A.P and be extinguished, and be discharged to the outside.

[0773] In this embodiment, even if the polarity of the CT magnet 530 and the arc extinguishing magnet 634 is changed, the formed arc path A.P is formed so as to be directed toward the width direction of the grid 620, which is the left-right direction in the illustrated embodiment. Further, the formed arc path A.P is formed so as to be directed toward the grid cover 630 located at a position opposite to each contact 311, 321.

[0774] Further, even in the case where the direction of the current flowing in each contact 311, 321 is changed, the arc path A.P is formed so as to be directed toward the end portions of the grid 620 and the grid cover 630.

[0775] Therefore, even if the polarity of the arc extinguishing magnet 634 and the direction of the current flowing are changed, the generated arc can rapidly move along the arc path A.P and be extinguished.

[0776] Further, the CT magnet 530 and the arc extinguishing magnet 634 respectively form a secondary magnetic field S.M.F. Each secondary magnetic field S.M.F is formed so as to be directed in the same direction as the primary magnetic field M.M.F formed between the CT magnet 530 and the arc extinguishing magnet 634.

[0777] Therefore, it is possible to strengthen the intensity of the magnetic field for forming the arc path A.P. As a result, since the intensity of the electromagnetic force is also strengthened, the generated arc can rapidly move along the arc path A.P toward the arc extinguishing portion 600 and be extinguished.

[0778] Figure 41

[0779] Reference will now be made in detail to the processes of forming an arc path A.P by an arc extinguishing portion 700 of another embodiment of the present application. Figure 42

[0780] ​As described above, the arc extinguishing portion 700 of the present embodiment includes the arc extinguishing magnet portion 770. The arc extinguishing magnet portion 770 includes the first arc extinguishing magnet 771 provided to the first housing portion 761, the second arc extinguishing magnet 772 provided to the second housing portion 762, and the third arc extinguishing magnet 773 provided to the third housing portion 763.

[0781] Each of the arc extinguishing magnets 771, 772, 773 forms a secondary magnetic field S.M.F. In addition, a primary magnetic field M.M.F. can be formed between each of the arc extinguishing magnets 771, 772, 773.

[0782] At this time, the second face 772b of the second arc extinguishing magnet 772 and the second face 773b of the third arc extinguishing magnet 773, which are opposite to each other, can be magnetized to the same polarity.

[0783] In addition, the first face 771a of the first arc extinguishing magnet 771, which is the face facing the grid 720, can be magnetized to the same polarity as the second face 772b of the second arc extinguishing magnet 772 and the second face 773b of the third arc extinguishing magnet 773.

[0784] Referring to Figure 41 , a front surface of the arc extinguishing portion 700 of another embodiment of the present application is shown. In addition, referring to Figure 41 , a bottom surface of the arc extinguishing portion 700 of another embodiment of the present application is shown.

[0785] The first face 771a of the first arc extinguishing magnet 771, which is the face facing the grid 720, is magnetized to the S pole. Thus, the second face 771b of the first arc extinguishing magnet 771, which is the face opposite to the grid 720, is magnetized to the N pole. The first arc extinguishing magnet 771 forms a secondary magnetic field S.M.F. as a magnetic field formed between the first face 771a and the second face 771b.

[0786] The first face 772a of the second arc extinguishing magnet 772, which is the face opposite to the first arc extinguishing magnet 771, is magnetized to the N pole. Thus, the second face 772b of the second arc extinguishing magnet 772, which is the face facing the first arc extinguishing magnet 771, is magnetized to the S pole. The second arc extinguishing magnet 772 forms a secondary magnetic field S.M.F. as a magnetic field formed between the first face 772a and the second face 772b.

[0787] The first face 773a of the third arc extinguishing magnet 773, i.e., the face of the third arc extinguishing magnet 773 on the side opposite the first arc extinguishing magnet 771, is magnetized as an N pole. Thus, the second face 773b of the third arc extinguishing magnet 773, i.e., the face of the third arc extinguishing magnet 773 on the side facing the first arc extinguishing magnet 771, is magnetized as an S pole. The third arc extinguishing magnet 773 forms a secondary magnetic field S.M.F. as a magnetic field formed between the first face 773a and the second face 773b.

[0788] In addition, a primary magnetic field M.M.F. is formed between the first arc extinguishing magnet 771 and the second arc extinguishing magnet 772. Specifically, the primary magnetic field M.M.F. is formed in the direction from the second face 771b of the first arc extinguishing magnet 771 toward the second face 772b of the second arc extinguishing magnet 772, i.e., in the direction from the first arc extinguishing magnet 771 toward the left side in the illustrated embodiment.

[0789] A primary magnetic field M.M.F. is also formed between the first arc extinguishing magnet 771 and the third arc extinguishing magnet 773. Specifically, the primary magnetic field M.M.F. is formed in the direction from the second face 771b of the first arc extinguishing magnet 771 toward the second face 773b of the third arc extinguishing magnet 773, i.e., in the direction from the first arc extinguishing magnet 771 toward the right side in the illustrated embodiment.

[0790] In Figure 42 In (a) of FIG. 17, the current flowing in each contact 311, 321 is in the direction from the paper, i.e., the direction in which the current flowing in the air circuit breaker 10 is transmitted to the power source or load through the fixed contact 310.

[0791] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 is contacted, the path A.P. of the arc can be anticipated.

[0792] That is, the electromagnetic force formed by the primary magnetic field M.M.F., the secondary magnetic field S.M.F., and the current flowing in each contact 311, 321 is formed in the direction toward the right side of the side edge of the grid 720, i.e., the upper side in the illustrated embodiment. Thus, the path A.P. of the arc is also formed toward the right side of the upper side.

[0793] In Figure 41 In (b) of FIG. 17, the current flowing in each contact 311, 321 is in the direction into the paper, i.e., the direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321.

[0794] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 is contacted, the path A.P. of the arc can be anticipated.

[0795] That is, the electromagnetic force formed by the main magnetic field M.M.F, the secondary magnetic field S.M.F, and the current flowing in each contact 311, 321 is formed in a direction toward the other side edge of the grid 720, which is the left side in the illustrated embodiment.

[0796] In Figure 42 (a), the current flowing in each contact 311, 321 is in a direction toward the arc extinguishing portion 700, that is, a direction in which the current flowing in the air circuit breaker 10 is transmitted to the outside power source or load through each contact 311, 321.

[0797] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 contacts, the path A.P of the arc can be anticipated.

[0798] That is, the electromagnetic force formed by the main magnetic field M.M.F, the secondary magnetic field S.M.F, and the current flowing in each contact 311, 321 is formed in a direction toward the other side edge of the grid 720, which is the left side in the illustrated embodiment.

[0799] Although not illustrated, it can be understood that, as in the embodiment illustrated in Figure 41 (a), in this embodiment, the path A.P of the arc is formed toward the right side of the grid 720.

[0800] In Figure 43 (b), the current flowing in each contact 311, 321 is in a direction toward the arc extinguishing portion 700, that is, a direction in which the current flowing in the air circuit breaker 10 is transmitted to the outside power source or load through each contact 311, 321.

[0801] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 contacts, the path A.P of the arc can be anticipated.

[0802] That is, the electromagnetic force formed by the main magnetic field M.M.F, the secondary magnetic field S.M.F, and the current flowing in each contact 311, 321 is formed in a direction toward the other side edge of the grid 720, which is the left side in the illustrated embodiment.

[0803] Although not illustrated, it can be understood that, as in the embodiment illustrated in Figure 44 (a), in this embodiment, the path A.P of the arc is formed toward the right side of the grid 720.

[0804] As described above, the end portions of the grid 720 in the left and right directions can be in a pointed shape. Thus, the arc can flow along the formed path A.P of the arc and enter the end portions of the grid 720.

[0805] Further, the arc path A.P is formed toward the grid cover 730 located on the upper side of the grid 720. The grid cover 730 is provided with a through-hole portion 732a of an upper frame 732 which communicates with the outside and a through-hole 734a of a mesh portion 733.

[0806] Therefore, the generated arc can be rapidly moved along the formed arc path A.P and be extinguished, and discharged to the outside.

[0807] Referring to Figure 43 , a front surface of the arc extinguishing portion 700 of another embodiment of the present application is shown. Further, referring to Figure 43 , a bottom surface of the arc extinguishing portion 700 of another embodiment of the present application is shown.

[0808] The first surface 771a of the first arc extinguishing magnet 771, i.e., the surface of the first arc extinguishing magnet 771 on the side toward the grid 720 is magnetized as an N pole. Thereby, the second surface 771b of the first arc extinguishing magnet 771, i.e., the surface of the first arc extinguishing magnet 771 on the other side opposite to the grid 720 is magnetized as an S pole. The first arc extinguishing magnet 771 forms a secondary magnetic field S.M.F as a magnetic field formed between the first surface 771a and the second surface 771b.

[0809] The first surface 772a of the second arc extinguishing magnet 772, i.e., the surface of the second arc extinguishing magnet 772 on the side opposite to the first arc extinguishing magnet 771 is magnetized as an S pole. Thereby, the second surface 772b of the second arc extinguishing magnet 772, i.e., the surface of the second arc extinguishing magnet 772 on the other side toward the first arc extinguishing magnet 771 is magnetized as an N pole. The second arc extinguishing magnet 772 forms a secondary magnetic field S.M.F as a magnetic field formed between the first surface 772a and the second surface 772b.

[0810] The first surface 773a of the third arc extinguishing magnet 773, i.e., the surface of the third arc extinguishing magnet 773 on the side opposite to the first arc extinguishing magnet 771 is magnetized as an S pole. Thereby, the second surface 773b of the third arc extinguishing magnet 773, i.e., the surface of the third arc extinguishing magnet 773 on the other side toward the first arc extinguishing magnet 771 is magnetized as an N pole. The third arc extinguishing magnet 773 forms a secondary magnetic field S.M.F as a magnetic field formed between the first surface 773a and the second surface 773b.

[0811] Further, a primary magnetic field M.M.F is formed between the first arc extinguishing magnet 771 and the second arc extinguishing magnet 772. Specifically, the primary magnetic field M.M.F is formed in a direction from the second surface 772b of the second arc extinguishing magnet 772 toward the second surface 771b of the first arc extinguishing magnet 771, i.e., in a direction toward the right side of the second arc extinguishing magnet 772 in the illustrated embodiment.

[0812] The main magnetic field M.M.F is also formed between the first arc extinguishing magnet 771 and the third arc extinguishing magnet 773. Specifically, the main magnetic field M.M.F is formed in a direction from the second face 773b of the third arc extinguishing magnet 773 toward the second face 771b of the first arc extinguishing magnet 771, i.e., in a direction toward the left side of the third arc extinguishing magnet 773 in the illustrated embodiment.

[0813] In Figure 44 In (a) of FIG. 17, the current flowing in each contact 311, 321 is in a direction from the paper, i.e., in a direction in which the current flowing in the air circuit breaker 10 is transmitted to the external power source or load through the fixed contact 310.

[0814] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 contacts, the path A.P of the arc can be anticipated.

[0815] That is, the electromagnetic force formed by the main magnetic field M.M.F, the secondary magnetic field S.M.F, and the current flowing in each contact 311, 321 is formed in a direction toward the one side edge of the grid 720, i.e., in a direction toward the left side of the upper side in the illustrated embodiment. Thus, the path A.P of the arc is also formed toward the left side of the upper side.

[0816] In Figure 43 In (b) of FIG. 17, the current flowing in each contact 311, 321 is in a direction into the paper, i.e., in a direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321.

[0817] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 contacts, the path A.P of the arc can be anticipated.

[0818] That is, the electromagnetic force formed by the main magnetic field M.M.F, the secondary magnetic field S.M.F, and the current flowing in each contact 311, 321 is formed in a direction toward the other side edge of the grid 720, i.e., in a direction toward the right side of the upper side in the illustrated embodiment. Thus, the path A.P of the arc is also formed toward the right side of the upper side.

[0819] In Figure 44 In (a) of FIG. 17, the current flowing in each contact 311, 321 is in a direction toward the arc extinguishing portion 700, i.e., in a direction in which the current flowing in the external power source or load is transmitted to the air circuit breaker 10 through each contact 311, 321.

[0820] Here, when the Ampere's left-hand rule is used at the position where each contact 311, 321 contacts, the path A.P of the arc can be anticipated.

[0821] That is, the electromagnetic force formed by the main magnetic field MMF, the secondary magnetic field SMF and the current flowing at each contact 311, 321 is formed along the direction of entering the paper, that is, towards the grid 720.

[0822] Although not illustrated, it is understandable, such as Figure 43 In the embodiment shown in (a), the path AP of the electric arc is formed toward the left side of the grid 720.

[0823] exist ​ In (b), the current flowing through each contact 311, 321 is in the direction of the arc extinguishing section 700, that is, the direction in which the current flowing through the air circuit breaker 10 is transmitted to the external power source or load through each contact 311, 321.

[0824] Here, when Ampere's left-hand rule is applied at the contact points 311 and 321, the path AP of the arc can be anticipated.

[0825] That is, the electromagnetic force formed by the main magnetic field MMF, the secondary magnetic field SMF and the current flowing at each contact 311, 321 is formed along the direction of entering the paper, that is, towards the grid 720.

[0826] Although not illustrated, it is understandable, such as ​ In the embodiment shown in (a), the path AP of the electric arc is formed toward the right side of the grid 720.

[0827] As described above, the left and right ends of the grid 720 can be pointed. Therefore, the electric arc can flow along the path AP of the formed arc and enter the ends of the grid 720.

[0828] Furthermore, the path AP of the electric arc is formed toward the grid cover 730 located on the upper side of the grid 720. The grid cover 730 is provided with a through hole 732a of the upper frame 732 communicating with the outside and a through hole 734a of the mesh portion 733.

[0829] Therefore, the generated electric arc can move rapidly along the path AP of the formed arc and be extinguished, discharged to the outside.

[0830] In this embodiment, even if the polarity of each arc-extinguishing magnet 771, 772, 773 changes, the path AP of the formed arc is formed in the width direction of the grille 720, which is the left-right direction in the illustrated embodiment. In addition, the path AP of the formed arc is formed towards the grille cover 730 located in the opposite position to each contact 311, 321.

[0831] Further, even if the direction of the current flowing in each contact 311, 321 is changed, the path A.P of the arc is formed toward the end of the grid 720 and the grid cover 730.

[0832] Therefore, even if the polarity of each arc extinguishing magnet 771, 772, 773 and the direction of the current flowing is changed, the generated arc can be rapidly moved along the path A.P of the arc and extinguished.

[0833] Further, each arc extinguishing magnet 771, 772, 773 forms a secondary magnetic field S.M.F. Each secondary magnetic field S.M.F. is formed toward the same direction as the primary magnetic field M.M.F. formed between each arc extinguishing magnet 771, 772, 773.

[0834] Therefore, the strength of the magnetic field for forming the path A.P of the arc can be strengthened. As a result, the strength of the electromagnetic force is also strengthened, and thus the generated arc can be rapidly moved along the path A.P of the arc toward the arc extinguishing portion 700 and extinguished.

[0835] The above has been described with reference to the preferred embodiments of the present application, but it is understood that those skilled in the art can make various modifications and changes to the present application within the scope of the idea and the range of the present application recited in the claims.

[0836] Industrial Applicability

[0837] The present application relates to an air circuit breaker, and can provide an air circuit breaker capable of effectively extinguishing an arc generated due to current interruption, and thus has industrial applicability.

Claims

1. An air circuit breaker, wherein, include: The upper cover creates a space inside; Fixed contacts are accommodated in the space of the upper cover; A movable contact, accommodated in the space of the upper cover, is located adjacent to the fixed contact and can move toward or away from the fixed contact. An arc-extinguishing part, housed in the space of the upper cover, is located adjacent to the fixed contact and extinguishes the electric arc extending from the fixed contact toward the movable contact. as well as The magnet part, which is attached to the upper cover, is located near the fixed contact and forms a magnetic field that applies an electromagnetic force to the electric arc. The upper cover includes: The first upper cover covers the fixed contact on the side opposite to the movable contact, and forms a space inside to accommodate a part of the arc extinguishing part and the fixed contact; as well as The second upper cover, which is combined with the first upper cover, is located on the other side of the fixed contact facing the movable contact, and has a space inside to accommodate the remaining part of the arc extinguishing part and the movable contact; The cover magnet portion is coupled to either the first upper cover or the second upper cover, and extends toward the remaining one of the first upper cover and the second upper cover.

2. The air circuit breaker according to claim 1, wherein, The cover magnet is configured to surround the fixed contact on one side of the fixed contact or on the opposite side of the fixed contact.

3. The air circuit breaker according to claim 1, wherein, The fixed contacts are provided in a plurality of those contacts, and are spaced apart from each other along one direction. The cover magnet is provided with a plurality of magnets, and is arranged spaced apart from each other along the said one direction. The plurality of fixed contacts are respectively disposed between adjacent cover magnets in the plurality of cover magnets.

4. The air circuit breaker according to claim 3, wherein, The upper surfaces of the plurality of said cover magnets are magnetized to have the same polarity as each other.

5. The air circuit breaker according to claim 1, wherein, The upper cover extends in one direction, and the two ends of the upper cover in that direction surround the fixed contact.

6. The air circuit breaker according to claim 5, wherein, The fixed contacts are provided in a plurality of manner and are spaced apart from each other along the said direction. The cover magnet is provided in a plurality of portions and is respectively disposed between the two ends of the upper cover and the plurality of fixed contacts.

7. The air circuit breaker according to claim 5, wherein, The fixed contacts are provided in three parts and are spaced apart from each other along the said direction. The cover magnet portion includes: The first cover magnet is located at one end of the upper cover in the one direction; The second cover magnet is configured to be opposite the first cover magnet, separated by any one of the three fixed contacts located on one side in the direction. The third cover magnet is configured to face the second cover magnet, separated from the third fixed contact by another fixed contact located in the middle of the three fixed contacts in the one direction; and The fourth cover magnet is configured to be opposite the third cover magnet, separated by the remaining one of the three fixed contacts located on the other side of the direction.

8. The air circuit breaker according to claim 7, wherein, The upper surfaces of the first cover magnet, the second cover magnet, the third cover magnet, and the fourth cover magnet are respectively magnetized to the S pole.

9. An air circuit breaker, wherein, include: The upper cover creates a space inside; Fixed contacts are accommodated in the space of the upper cover; A movable contact is rotatably accommodated in the space of the upper cover, located behind the fixed contact, and in contact with or separates from the fixed contact; An arc-extinguishing part, housed in the space of the upper cover, is located above the fixed contact and extinguishes the electric arc generated between the fixed contact and the movable contact; as well as The magnet part, which is attached to the upper cover, is located to the left or right of the fixed contact, forming a magnetic field that applies an electromagnetic force to the electric arc. The upper cover includes: The first upper cover covers the fixed contact on the side opposite to the movable contact, and forms a space inside to accommodate a part of the arc extinguishing part and the fixed contact; as well as The second upper cover, which is combined with the first upper cover, is located on the other side of the fixed contact facing the movable contact, and has a space inside to accommodate the remaining part of the arc extinguishing part and the movable contact; The cover magnet portion is coupled to either the first upper cover or the second upper cover, and extends toward the remaining one of the first upper cover and the second upper cover.

10. The air circuit breaker according to claim 9, wherein, The fixed contacts are provided in a plurality of those, and are spaced apart from each other in the left-right direction. The cover magnet is provided in a plurality of positions, and is respectively disposed to the left of the leftmost fixed contact, to the right of the rightmost fixed contact, and between the plurality of fixed contacts.

11. The air circuit breaker according to claim 10, wherein, The upper surfaces of the plurality of said cover magnets are magnetized to the same polarity.

12. The air circuit breaker according to claim 9, wherein, The upper cover extends in the left-right direction. The fixed contacts are provided in three places and are spaced apart from each other in the left-right direction inside the upper cover. The cover magnet portion includes: The first cover magnet is attached to the upper cover to the left of the fixed contact located on the far left. The second cover magnet is attached to the upper cover to the right of the fixed contact located on the far left. The third cover magnet is attached to the upper cover to the right of the fixed contact located in the center; and The fourth cover magnet is attached to the upper cover to the right of the fixed contact located on the far right.

13. The air circuit breaker according to claim 12, wherein, The upper surfaces of the first cover magnet, the second cover magnet, the third cover magnet, and the fourth cover magnet are respectively magnetized to the S pole.

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