Breaker

Abstract

To provide a breaker capable of suppressing spread of an arc when cutting a conductor.SOLUTION: A breaker 1 includes a conductor 30, a holder 10 holding the conductor 30 and having a first space 11 and a second space 12 separated by the conductor 30, a pusher 20 arranged in the first space 11, and a drive source 40 that moves the pusher 20 from the first space 11 to the second space 12. The conductor 30 includes a partition 33 separating the first space 11 and the second space 12, and a pair of embedded portions 32 continuous to the partition 33 with the partition 33 interposed therebetween, and at least one of the pair of embedded portions 32 includes a thin portion 321 that is continuous with the partition 33 and a thick portion 322 that is continuous with the thin portion 321 on the opposite side of the partition 33 and is thicker than the thin portion 321.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a cutoff device.

Background Art

[0002] Conventionally, when an overcurrent such as a short-circuit current flows through an electric circuit mounted on an automobile or the like, a cutoff device that prevents major damage by cutting a conductor that forms part of the electric circuit has been studied (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, due to the progress of electric vehicles, machine tools, etc., the required energization capacity of cutoff devices has been increasing. To ensure the energization capacity, it is necessary to increase the cross-sectional area of the conductors of the cutoff device. Here, a conductor with a large cross-sectional area is likely to generate an arc when broken. Also, an arc is likely to spread starting from the broken cross-section where the conductor was cut. In particular, a spreading arc may cause cutoff failure of the cutoff device or damage to the cutoff device itself.

[0005] Therefore, an object of the present disclosure is to provide a cutoff device capable of suppressing the spread of an arc when a conductor is cut.

Means for Solving the Problems

[0006] A circuit breaker according to one aspect of the present disclosure comprises a conductor, a holder that holds the conductor and has a first space and a second space separated by the conductor, a pusher disposed in the first space, and a drive source for moving the pusher from the first space to the second space, wherein the conductor has a partition separating the first space and the second space, and a pair of embedded portions continuous with the partition on either side of the partition, and at least one of the pair of embedded portions has a thin-walled portion continuous with the partition, and a thick-walled portion that is continuous with the thin-walled portion on the opposite side from the partition and is thicker than the thin-walled portion. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a circuit breaker capable of suppressing the spread of the arc when a conductor is cut. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view showing the configuration of a circuit breaker according to an embodiment. [Figure 2] Figure 2 is a cross-sectional view showing the configuration of a circuit breaker according to an embodiment. [Figure 3] Figure 3 is a plan view showing a pair of buried sections and partitioned sections according to the embodiment. [Figure 4] Figure 4 is a cross-sectional view showing a magnified view of the area enclosed by the dashed line in Figure 2. [Figure 5] Figure 5 is a cross-sectional view of the circuit breaker showing the state after the conductive material has been cut in the embodiment. [Figure 6] Figure 6 is a cross-sectional view of the circuit breaker showing the state after the conductor has been cut according to Modification 1. [Figure 7] Figure 7 is a cross-sectional view showing the bottom shape of the modified example 2. [Figure 8] Figure 8 is a cross-sectional view showing a conductor according to modified example 3. [Modes for carrying out the invention]

[0009] A circuit breaker according to one aspect of the present disclosure comprises a conductor, a holder that holds the conductor and has a first space and a second space separated by the conductor, a pusher disposed in the first space, and a drive source for moving the pusher from the first space to the second space, wherein the conductor has a partition separating the first space and the second space, and a pair of embedded portions continuous with the partition on either side of the partition, and at least one of the pair of embedded portions has a thin-walled portion continuous with the partition, and a thick-walled portion that is continuous with the thin-walled portion on the opposite side from the partition and is thicker than the thin-walled portion.

[0010] According to this, in a conductor, at least one of a pair of embedded sections is provided with a thin-walled section and a thick-walled section that is thicker than the thin-walled section. When the conductor is cut, the section continuous with the thin-walled section is cut. In other words, the cut occurs at a point with a smaller cross-sectional area than the thick-walled section, so the area where the arc is generated can be reduced. Therefore, it is possible to suppress the spreading of the arc.

[0011] Furthermore, in the thin-walled portion, the main surface on the second space side may be positioned closer to the first space than the main surface on the second space side in the thick-walled portion.

[0012] According to this, in the thin-walled portion of the conductor, the main surface on the second space side is positioned closer to the first space than the main surface on the second space side in the thick-walled portion. In other words, a recess is formed in the conductor on the second space side of the thin-walled portion. Part of the holder is embedded in this recess. Therefore, when the pusher moves from the first space to the second space and pushes the compartment toward the second space, part of the holder can act like a wedge, making it possible to cut the conductor smoothly.

[0013] Furthermore, the length of the thin-walled portion in the width direction, which is the direction in which the thin-walled portion intersects the extension direction extending from the thick-walled portion, may be smaller than the length of the thick-walled portion in the width direction.

[0014] According to this, since the length in the width direction of the thin portion is smaller than the length in the width direction of the thick portion, the cross-sectional area of the portion cut by the pusher can be made smaller. That is, since the arc generation area can be made smaller, it is possible to further suppress the spread of the arc.

[0015] Further, the boundary portion between the thin portion and the thick portion may have an inclined surface.

[0016] When an arc occurs or when the drive source operates to move the pusher from the first space to the second space, gas is generated. These gases enter the gap between the thin portion and the holder. Here, if the boundary between the thin portion and the thick portion is formed in a stepped shape, gas may accumulate at the corner portion, which may damage the holder. In this embodiment, since an inclined surface is formed at the boundary portion between the thin portion and the thick portion, the gas can flow smoothly along the inclined surface, and it is possible to suppress the gas from staying inside the holder. Therefore, damage to the holder caused by gas can be suppressed.

[0017] Further, in a state after the pusher cuts the partition portion of the conductor and moves from the first space to the second space by the drive source, the pusher has a first facing portion facing one of the pair of embedded portions and a second facing portion facing the other of the pair of embedded portions. In a view in the moving direction of the pusher, the shortest first length on the outer surface of the pusher connecting the first facing portion and the second facing portion may be longer than the shortest second length on the outer surface of the pusher connecting the first facing portion, the bottom portion of the pusher, and the second facing portion in a view in a direction orthogonal to the moving direction of the pusher.

[0018] According to this, in a state where the pusher has moved to the second space, since the first length is longer than the second length, the arc tries to pass through a path connecting the first facing portion forming the second length, the bottom portion of the pusher, and the second facing portion. If a member for suppressing the arc is arranged near the bottom portion of the pusher, the arc can be suppressed by the member. Therefore, the spread of the arc can be further suppressed.

[0019] Also, in a state after the pusher moves from the first space to the second space by cutting the partition portion of the conductor by the drive source, the pusher has a first opposing portion facing one of the pair of embedded portions and a second opposing portion facing the other of the pair of embedded portions. In a view in the moving direction of the pusher, the shortest first length on the outer surface of the pusher connecting the first opposing portion and the second opposing portion may be longer than the shortest third length on the outer surfaces of the pusher and the partition portion connecting the first opposing portion, the bottom of the partition portion overlapping the bottom of the pusher, and the second opposing portion in a view in a direction orthogonal to the moving direction of the pusher.

[0020] According to this, in a state where the pusher has moved to the second space, since the third length is longer than the second length, the arc tends to pass through a path connecting the first opposing portion forming the third length, the bottom of the partition portion overlapping the bottom of the pusher, and the second opposing portion. If a member for suppressing the arc is arranged near the partition portion after cutting, the arc can be suppressed by the member. Therefore, the spread of the arc can be further suppressed.

[0021] Further, a groove may be formed in the partition portion on the outer side of the outer surface of the pusher in a view in the moving direction of the pusher.

[0022] According to this, in a view in the moving direction of the pusher, since a groove is formed in the partition portion on the outer side of the outer surface of the pusher, when the pusher pushes the partition portion into the second space, the partition portion is cut starting from the groove. Therefore, it is possible to smoothly cut the conductor.

[0023] Further, a groove may be formed in the thin portion along the outer surface of the pusher.

[0024] According to this design, a groove is formed along the outer surface of the pusher in the thin-walled section, so the groove is embedded in the holder. As a result, the cross-sectional area of ​​the conductor's cutting point can also be reduced by the groove, making it possible to further suppress the arc's spread.

[0025] Furthermore, the bottom of the pusher may have a projection that protrudes laterally at a location corresponding to the groove.

[0026] According to this design, a projection extending laterally is formed at the bottom of the pusher where it corresponds to the groove, allowing the projection to be positioned close to the groove. Therefore, the projection and groove enable smoother cutting of the conductive material.

[0027] Furthermore, the length of the projection in the direction of movement of the pusher may be less than the thickness of the thin-walled portion.

[0028] If a projection is provided along the entire length of the pusher, the gap between the holder and the pusher (projection) becomes narrower compared to when no projection is formed on the pusher. When an arc is generated, a large pressure is generated inside the circuit breaker (holder). Therefore, if a projection is provided along the entire length of the pusher, the holder and pusher may be damaged by the generated pressure. In this embodiment, the projection is formed such that its length in the direction of movement of the pusher is smaller than the thickness of the thin-walled section. This allows for the conductor to be broken while suppressing fracture of the holder and pusher, as well as suppressing displacement of the pusher.

[0029] (Embodiment) Hereinafter, an embodiment of the present invention (including its modifications) of a circuit breaker will be described with reference to the drawings. Note that the embodiments described below are all general or specific examples. The numerical values, shapes, materials, components, arrangement and connection configurations of components, manufacturing processes, and the order of manufacturing processes shown in the following embodiments are examples only and are not intended to limit the present invention. Dimensions in each figure are not precisely illustrated. In each figure, the same or similar components are denoted by the same reference numerals.

[0030] In the following description and drawings, the longitudinal direction of the conductor is defined as the X-axis direction, the width direction of the conductor as the Y-axis direction, and the thickness direction of the conductor as the Z-axis direction. These X-axis, Y-axis, and Z-axis directions intersect each other (orthogonal in this embodiment). Although the Z-axis direction may not be vertical depending on the usage, for the sake of explanation below, the Z-axis direction will be described as vertical.

[0031] In the following explanation, the X-axis positive direction refers to the direction of the X-axis arrow, and the X-axis negative direction refers to the opposite direction. When simply referred to as the X-axis direction, it refers to either the X-axis positive direction or the X-axis negative direction, or either direction. The same applies to the Y-axis and Z-axis directions. Expressions indicating relative directions or orientations, such as parallel and orthogonal, include cases where they are not strictly those directions or orientations. For example, two directions being parallel means not only that the two directions are perfectly parallel, but also that they are substantially parallel, i.e., they may have a difference of, for example, a few percent.

[0032] [Configuration of the circuit breaker] The following describes the circuit breaker according to the embodiment. First, the configuration of the circuit breaker according to the embodiment will be described with reference to Figures 1 and 2. Figure 1 is a perspective view showing the configuration of the circuit breaker 1 according to the embodiment. Figure 2 is a cross-sectional view showing the configuration of the circuit breaker 1 according to the embodiment.

[0033] The circuit breaker 1 comprises a holder 10, a conductor 30, a pusher 20, and a drive source 40. Here, the circuit breaker 1 is an electrical circuit breaker that is mounted on vehicles such as automobiles, electrical products such as home appliances, etc., and interrupts the electrical circuit when an overcurrent occurs. Vehicles include, for example, vehicles equipped with battery packs such as BEVs (Battery Electric Vehicles) and PHEVs (Plug-in Hybrid Vehicles). Note that the circuit breaker 1 may be mounted on objects with electrical circuits other than automobiles and electrical products. Furthermore, an overcurrent is a high current that does not normally flow through the conductor 30, and is an abnormal current that flows, for example, when a malfunction occurs in another device.

[0034] The holder 10 is the part that holds the pusher 20, the conductor 30, and the drive source 40. The holder 10 houses the pusher 20, the conductor 30, and the drive source 40 with parts of the conductor 30 and the drive source 40 exposed. Inside the holder 10, a first space 11 and a second space 12 are formed, separated by the conductor 30. A cooling section (not shown) for cooling the arc is located in the second space 12. For the cooling section, for example, sand, alumina, hydrogen gas, oil, steel wool, glass wool, etc. can be used.

[0035] Specifically, the holder 10 includes a first holder 110 for holding the pusher 20 and the conductor 30, a second holder 120 for holding the drive source 40, a third holder 130 for receiving the moved pusher 20, and a cover portion 140 that covers the first holder 110, the second holder 120, and the third holder 130.

[0036] The first holder 110 has an upper holder 111 and a lower holder 112, which are arranged side by side in the Z-axis direction. The upper holder 111 is positioned above the conductor 30 and is a cylindrical insulating member having a first opening 113 that penetrates in the Z-axis direction (vertical direction). A first flange portion 114 is formed at the lower end of the upper holder 111, which protrudes outward around its entire circumference.

[0037] The lower holder 112 is a cylindrical insulating member positioned below the conductor 30 and having a second opening 115 that penetrates in the Z-axis direction (vertical direction). The conductor 30 is held in place by being sandwiched between the lower holder 112 and the upper holder 111. The second opening 115 is positioned coaxially with the first opening 113. The upper part of the second opening 115 is formed to be narrower in width (internal dimension) than the lower part. The inner circumferential surface forming the upper part of the second opening 115 and the inner circumferential surface forming the first opening 113 have a shape that roughly overlaps when viewed in the Z-axis direction. A second flange portion 116 is formed at the upper end of the lower holder 112, extending outward around its entire circumference.

[0038] The second holder 120 is a cylindrical insulating member positioned on top of the upper holder 111. In a view along the Z-axis, the drive source 40 is fitted through the center of the second holder 120 in the Z-axis direction. A recess 121 is formed on the lower surface of the second holder 120, which accommodates the upper part of the pusher 20.

[0039] The third holder 130 is a cylindrical insulating member positioned below the lower holder 112. The central part of the third holder 130 is closed in the Z-axis direction, and this part receives the moving pusher 20.

[0040] The cover portion 140 has a first cover 141 and a second cover 142. The first cover 141 covers the upper holder 111 and the second holder 120 from above. The drive source 40 protrudes from the first cover 141. A plate-shaped first protective body 161 is attached to the upper surface of the periphery of the first cover 141. As a result, the upper surface of the first flange portion 114 of the upper holder 111 is covered by the first cover 141 and the first protective body 161.

[0041] The second cover 142 covers the lower holder 112 and the third holder 130 from below. A plate-shaped second protective body 162 is attached to the lower surface of the periphery of the second cover 142. As a result, the lower surface of the second flange portion 116 of the lower holder 112 is covered by the second cover 142 and the second protective body 162.

[0042] As shown in Figure 1, the first protective body 161, the first cover 141, the upper holder 111, the lower holder 112, the second cover 142, and the second protective body 162 have fixing holes 163 formed at each corner. Fasteners (not shown) are attached to each fixing hole 163, thereby integrally fixing the first protective body 161, the first cover 141, the upper holder 111, the lower holder 112, the second cover 142, and the second protective body 162.

[0043] As shown in Figure 2, the pusher 20 is a cylindrical insulating member. The pusher 20 is supported from below by a conductor 30. A recess 23 is formed on the upper surface of the pusher 20 to accommodate the lower part of the drive source 40.

[0044] The drive source 40 is a gas generator that drives the pusher 20 toward the second space 12 by generating gas in the first space 11. The drive source 40 has a pair of electrode pins, a heating element connected to the pair of electrode pins, and fuel (explosives) placed near the heating element. The fuel is exposed from the lower end of the drive source 40 in the housing recess 23 of the pusher 20. When the pair of electrode pins are energized based on the control of an external control device, the heating element generates heat and raises the temperature of the fuel. As a result the fuel burns and gas is generated in the housing recess 23. This generated gas causes the pusher 20 to move from the first space 11 toward the second space 12. In other words, the pusher 20 moves from above (positive Z-axis direction) to below (negative Z-axis direction) the conductor 30.

[0045] The conductor 30 is a plate-shaped conductive member that is elongated in the X-axis direction, and its upper surface is formed to be flat overall. The conductor 30 has a pair of tip portions 31, a pair of embedded portions 32, and a partitioned portion 33.

[0046] The pair of tip portions 31 are parts that protrude outward from the first holder 110. Specifically, of the pair of tip portions 31, one tip portion 31 is the end in the negative X-axis direction, and the other tip portion 31 is the end in the positive X-axis direction. The pair of embedded portions 32 are parts located inward in the X-axis direction from the pair of tip portions 31, and each is continuous with the pair of tip portions 31. The pair of embedded portions 32 are embedded within the first holder 110.

[0047] The partitioned section 33 is the area between the pair of buried sections 32 and is continuous with the pair of buried sections 32. The partitioned section 33 spans the internal space of the first holder 110 so as to separate the first space 11 and the second space 12.

[0048] Figure 3 is a plan view showing a pair of embedded sections 32 and partitioned sections 33 according to the embodiment. In Figure 3, the internal shapes of the cylindrical portions of the first space 11 and the second space 12 in the first holder 110 are shown by dashed lines, and the external shape of the pusher 20 is shown by a dashed line. Here, the gap S between the external shape of the internal space of the first holder 110 and the external shape of the pusher 20 is 0.2 mm or more and 1.2 mm or less.

[0049] As shown in Figures 2 and 3, each buried portion 32 has a thin-walled portion 321 that is continuous with the partition portion 33, and a thick-walled portion 322 that is continuous with the thin-walled portion 321 on the side opposite to the partition portion 33.

[0050] As shown in Figure 2, the thickness t1 (length in the Z-axis direction) of the thin-walled portion 321 is thinner than the thickness t2 of the thick-walled portion 322. Furthermore, the main surface 321a (bottom surface) of the thin-walled portion 321 on the second space 12 side is positioned closer to the first space 11 than the main surface 322a (bottom surface) of the thick-walled portion 322 on the second space 12 side. In addition, an inclined surface 323 is formed at the boundary between the main surface 321a of the thin-walled portion 321 and the main surface 322a of the thick-walled portion 322. The inclined surface 323 is inclined downwards as it moves away from the thin-walled portion 321.

[0051] As shown in Figure 3, the length W1 of the thin-walled portion 321 in the width direction (Y-axis direction), which intersects the extension direction (X-axis direction) in which the thin-walled portion 321 extends from the thick-walled portion 322, is smaller than the width direction length W2 of the thick-walled portion 322. The partitioned portion 33 extends uniformly in the X-axis direction with the same width direction length W1 as the thin-walled portion 321. At the boundary portion of the partitioned portion 33 with the thin-walled portion 33, the cross-sectional shape is approximately the same as that of the thin-walled portion 33.

[0052] Figure 4 is a cross-sectional view showing an enlarged view of the area enclosed by the dashed line L1 in Figure 2. As shown in Figure 4, first grooves 331 are formed in the main surface 33a (upper surface) on the first space 11 side and the main surface 33b (lower surface) on the second space 12 side of the partitioned portion 33. As shown in Figure 3, the first grooves 331 are provided at both ends of the partitioned portion 33 in the X-axis direction. The first grooves 331 are located outside the outer surface of the pusher 20 in the Z-axis direction view (view in the direction of movement of the pusher 20). The first grooves 331 are formed in a curved shape that protrudes outward in the X-axis direction to correspond to the outer surface of the pusher 20. When the pusher 20 moves from the first space 11 to the second space 12, the partitioned portion 33 is cut starting from these first grooves 331, because each first groove 331 is formed in the partitioned portion 33.

[0053] [Operation of the circuit breaker] Next, the operation of the circuit breaker 1 will be described. Before an overcurrent occurs, that is, under normal conditions, the circuit breaker 1 is in the state shown in Figure 2. When an overcurrent occurs in the electrical circuit of a vehicle or electrical product on which the circuit breaker 1 is installed, the pair of electrode pins of the drive source 40 are energized based on the control of an external control device of the circuit breaker 1. As a result, the heating element of the drive source 40 generates heat, raising the temperature of the fuel. When the fuel burns and gas is generated in the containment recess 23, the pusher 20 moves from the first space 11 to the second space 12. This movement cuts the compartment 33 of the conductor 30. The cut compartment 33 moves downward together with the pusher 20.

[0054] An arc is generated when the partitioned section 33 is cut. The portion of the partitioned section 33 that is cut by the pusher 20 has a cross-sectional shape that is generally equivalent to that of the thin-walled section 321. As described above, the thin-walled section 321 is thinner than the thick-walled section 322 and also shorter in length in the width direction, so the cross-sectional area of ​​the cut portion is smaller than that of the thick-walled section 322. This cut portion is also where the arc is generated. If the cross-sectional area of ​​this cut portion can be reduced, the area where the arc is generated can be reduced, and the spread of the arc can be suppressed.

[0055] Figure 5 is a cross-sectional view of the cutoff device 1 showing the state after the conductor 30 has been cut in the embodiment. Figure 5 corresponds to Figure 2. More specifically, Figure 5 shows the state after the pusher 20 has moved from the first space 11 to the second space 12 by the drive source 40 after cutting the partitioned portion 33 of the conductor 30. In this state, the pusher 20 has a first opposing portion 21 that faces one of the pair of buried portions 32 in the negative X-axis direction, and a second opposing portion 22 that faces the other buried portion 32 in the positive X-axis direction. The first opposing portion 21 and the second opposing portion 22 are parts of the outer surface of the pusher 20 that face opposite each other in the X-axis direction. As shown in Figure 3, in a view along the Z-axis direction (view in the direction of movement of the pusher 20), the shortest length on the outer surface of the pusher 20 connecting the first opposing portion 21 and the second opposing portion 22 is defined as the first length D1. As shown in Figure 5, the first length D1 is a straight line along the XY plane when viewed in the Y-axis direction (a direction perpendicular to the direction of movement of the pusher 20). In the Y-axis direction, the shortest length on the outer surface of the pusher 20 connecting the first opposing part 21, the bottom of the pusher 20, and the second opposing part 22 is defined as the second length D2. It is preferable that the first length D1 be set to be longer than the second length D2. Because arcs tend to travel along shorter paths, the arc generated by cutting will pass through the second length D2. The arc passing through the second length D2 is cooled by passing near the cooling section, which further suppresses the spreading of the arc.

[0056] [Effects, etc.] As described above, the circuit breaker 1 according to the above embodiment includes a conductor 30, a holder 10 that holds the conductor 30 and has a first space 11 and a second space 12 separated by the conductor 30, a pusher 20 disposed in the first space 11, and a drive source 40 for moving the pusher 20 from the first space 11 to the second space 12. The conductor 30 has a partition portion 33 that separates the first space 11 and the second space 12, and a pair of embedded portions 32 that are continuous with the partition portion 33, with the partition portion 33 in between. At least one of the pair of embedded portions 32 has a thin-walled portion 321 that is continuous with the partition portion 33, and a thick-walled portion 322 that is continuous with the thin-walled portion 321 on the opposite side of the partition portion 33 and is thicker than the thin-walled portion 321.

[0057] According to this, in the conductor 30, at least one of the pair of embedded portions 32 is provided with a thin-walled portion 321 and a thick-walled portion 322 that is thicker than the thin-walled portion 321. When the conductor 30 is cut, the partitioned portion 33 continuous with the thin-walled portion 321 is cut. In other words, since the cut occurs at a location with a smaller cross-sectional area than the thick-walled portion 322, the area where the arc is generated can be reduced. Therefore, it is possible to suppress the spreading of the arc.

[0058] Furthermore, in the thin-walled portion 321, the main surface 321a on the second space 12 side is positioned closer to the first space 11 than the main surface 322a on the second space 12 side in the thick-walled portion 322.

[0059] According to this, in the thin-walled portion 321 of the conductor 30, the main surface 321a on the second space 12 side is positioned closer to the first space 11 than the main surface 322a on the second space 12 side in the thick-walled portion 322. As a result, a recess is formed in the conductor 30 on the second space 12 side of the thin-walled portion 321. Part of the lower holder 112 is embedded in this recess. Therefore, when the pusher 20 moves from the first space 11 to the second space 12 and pushes the partitioned portion 33 toward the second space 12, part of the lower holder 112 can act like a wedge, making it possible to cut the conductor 30 smoothly.

[0060] Furthermore, the length W1 of the thin-walled portion 321 in the width direction (Y-axis direction), which intersects the extension direction (X-axis direction) in which the thin-walled portion 321 extends from the thick-walled portion 322, is smaller than the length W2 of the thick-walled portion 322 in the width direction.

[0061] According to this, since the widthwise length W1 of the thin-walled portion 321 is smaller than the widthwise length W2 of the thick-walled portion 322, the cross-sectional area of ​​the portion cut by the pusher 20 can be made smaller. In other words, the area where the arc is generated can be made smaller, so the spreading of the arc can be suppressed more effectively.

[0062] Furthermore, the boundary between the thin-walled portion 321 and the thick-walled portion 322 has an inclined surface 323.

[0063] Gas is generated when an arc occurs or when the drive source 40 operates. These gases enter the lower holder 112 through the gap between the thin-walled portion 321 and the lower holder 112. If the boundary between the thin-walled portion 321 and the thick-walled portion 322 is formed in a stepped manner, the gas may accumulate at the corner and damage the lower holder 112. In this embodiment, an inclined surface 323 is formed at the boundary between the thin-walled portion 321 and the thick-walled portion 322, so that the gas flows smoothly along the inclined surface 323, and the accumulation of gas inside the lower holder 112 can be suppressed. Therefore, damage to the lower holder 112 caused by gas can be suppressed.

[0064] Furthermore, in the state after the pusher 20 has moved from the first space 11 to the second space 12 by the drive source 40, cutting through the partitioned portion 33 of the conductor 30, the pusher 20 has a first opposing portion 21 that faces one of the pair of embedded portions 32, and a second opposing portion 22 that faces the other of the pair of embedded portions 32. In a view of the direction of movement of the pusher 20 (view in the Z-axis direction), the shortest first length D1 on the outer surface of the pusher 20 connecting the first opposing portion 21 and the second opposing portion 22 is longer than the shortest second length D2 on the outer surface of the pusher 20 connecting the first opposing portion 21, the bottom of the pusher 20, and the second opposing portion 22 in a view in a direction perpendicular to the direction of movement of the pusher 20 (view in the Y-axis direction).

[0065] According to this, when the pusher 20 is in the second space 12, the first length D1 is longer than the second length D2, so the arc attempts to pass through a path connecting the first opposing part 21, which forms the second length D2, the bottom of the pusher 20, and the second opposing part 22. If a member (cooling part) for suppressing the arc is placed near the bottom of the pusher 20, the arc can be suppressed by this member. Therefore, the spreading of the arc can be further suppressed.

[0066] Furthermore, the second space 12 is provided with a cooling section for cooling the arc generated as a result of the cutting of the partitioned section 33.

[0067] According to this, a cooling section is provided in the second space 12 for cooling the arc generated due to the cutting of the partitioned section 33. Therefore, the arc can be cooled by the cooling section 50, and the spreading of the arc can be suppressed more reliably.

[0068] Furthermore, the partitioned portion 33 has a first groove 331 that is located on the outside of the outer surface of the pusher 20 when viewed in the direction of movement of the pusher 20 (viewed in the Z-axis direction).

[0069] According to this, in the view of the direction of movement of the pusher 20, a first groove 331 is formed in the compartment 33, located on the outside of the outer surface of the pusher 20. Therefore, when the pusher 20 pushes the compartment 33 into the second space 12, the compartment 33 is cut starting from the first groove 331. Thus, the conductor 30 can be cut smoothly.

[0070] Furthermore, since the gap S between the outer shape of the internal space of the first holder 110 and the outer shape of the pusher 20 is 0.2 mm or more and 1.2 mm or less, the arc is less likely to rotate circumferentially around the outer surface of the pusher 20. Therefore, the blocking performance can be improved.

[0071] (Other embodiments) Although the above-described embodiments of the circuit breaker have been explained, this disclosure is not limited to these embodiments. Without departing from the spirit of this disclosure, various modifications to these embodiments that a person skilled in the art could conceive, as well as forms constructed by combining components from different embodiments, may also be included in this disclosure. In the following description, parts identical to those in the above embodiments may be denoted by the same reference numerals, and their descriptions may be omitted.

[0072] For example, the above embodiment illustrates the case where the first length D1 is longer than the second length D2. However, the first length D1 may be longer than other reference lengths. Figure 6 is a cross-sectional view of the circuit breaker 1 showing the state after the conductor 30 according to Modification 1 has been cut. Figure 6 corresponds to Figure 5. In Figure 6, a third length D3, which is an example of another reference length, is shown. The third length D3 is the shortest length on the outer surfaces of the pusher 20 and compartment 33, connecting the first opposing portion 21, the bottom of the compartment 33 that overlaps the bottom of the pusher 20, and the second opposing portion 22, when viewed in the Y-axis direction. In other words, the first length D1 should be set to be longer than the third length D3. In this case, the arc will try to pass through the path connecting the first opposing portion 21, the bottom (lower surface) of the compartment 33, which forms the third length D3, and the second opposing portion 22. Since the bottom of the compartment 33 is located directly above the cooling portion, the arc can be brought closer to the cooling portion. Therefore, the spreading of the arc can be further suppressed.

[0073] Figure 7 is a cross-sectional view showing the bottom shape of the pusher 20A according to Modification 2. Specifically, Figure 7 corresponds to Figure 4. As shown in Figure 7, a projection 25 is formed on the bottom of the pusher 20A, projecting laterally at a location corresponding to the first groove 331. The projection 25 may be provided continuously along the entire length of the first groove 331 in a view along the Z-axis, or it may be provided intermittently. Alternatively, the projection 25 may be provided only at a position facing a portion of the first groove 331 in a view along the Z-axis. The length of the projection 25 in the Z-axis direction is smaller than the thickness of the thin-walled portion 321.

[0074] Thus, a projection 25 is formed on the bottom of the pusher 20A at a location corresponding to the first groove 331, so that the projection 25 can be positioned close to the first groove 331. Therefore, the projection 25 and the first groove 331 make it possible to cut the conductor 30 more smoothly.

[0075] Here, if the projection 25 is provided along the entire length of the pusher 20A, the gap between the first holder 110 and the pusher 20A (projection 25) becomes narrower than when the pusher does not have a projection. When an arc is generated, a large pressure is generated inside the shutoff device 1 (holder 10). Therefore, if the projection is provided along the entire length of the pusher 20A, the first holder 110 and the pusher 20A may be damaged by the generated pressure. In this embodiment, the projection 25 is formed such that the length in the direction of movement of the pusher 20A (Z-axis direction) is smaller than the thickness of the thin-walled portion 321. This makes it possible to break the conductor 30 while suppressing the breakage of the first holder 110 and the pusher 20A, as well as suppressing the displacement of the pusher 20A.

[0076] Figure 8 is a cross-sectional view showing the conductor 30b according to Modification 3. Specifically, Figure 8 corresponds to Figure 7. As shown in Figure 8, in Modification 3, the first groove 331 is not formed in the partitioned portion 33 of the conductor 30b, and a second groove 331b is formed in the thin-walled portion 321b. Specifically, a second groove 331b (groove) is formed on each main surface of the thin-walled portion 321b, along the outer surface of the pusher 20A. Therefore, each second groove 331b is embedded in the first holder 110. As a result, the cross-sectional area of ​​the cut portion of the conductor 30b can also be reduced by the second groove 331b, and the arc spreading can be further suppressed.

[0077] Furthermore, in the above embodiment, the example given was that the length W1 in the width direction of the thin-walled portion 321 is smaller than the length W2 in the width direction of the thick-walled portion 322. However, the length in the width direction of the thin-walled portion and the length in the width direction of the thick-walled portion may be equal.

[0078] Furthermore, in the above embodiment, a conductor 30 having a flat upper surface and an uneven lower surface was exemplified. However, a conductor having a flat lower surface and an uneven upper surface is also possible. In other words, in this case, the main surface (upper surface) on the first space 11 side in the thin-walled portion will be positioned closer to the second space than the main surface (upper surface) on the first space side in the thick-walled portion.

[0079] Furthermore, in the above embodiment, an example was given in which the first groove 331 is provided on the main surface 33a (upper surface) on the first space 11 side and the main surface 33b (lower surface) on the second space 12 side of the partitioned portion 33. However, the first groove may be formed on at least one of the main surfaces of the partitioned portion. Similarly, the second groove may be formed on at least one of the main surfaces of the thin-walled portion. Also, grooves may not be formed in the partitioned portion 33.

[0080] Furthermore, although the above embodiment illustrates a case where each of the pair of buried portions 32 has a thin-walled portion 321 and a thick-walled portion 322, it is also possible for only one of the buried portions to have a thin-walled portion and a thick-walled portion.

[0081] The present invention also includes forms constructed by arbitrarily combining the components included in the above embodiments and their modified examples. [Industrial applicability]

[0082] This disclosure is useful for a circuit breaker that interrupts an electrical circuit when an overcurrent occurs. [Explanation of Symbols]

[0083] 1. Circuit breaker 10 holders 11 First space 12 Second space 20, 20A pusher 21 First opposing section 22 Second Opposing Section 23 Receiving recess 25 Protrusion 30 Conductors 31 Tip 32 Buried section 33 Sections 33a, 33b, 321a, 322a Main surface 40 Power source 110 First Holder 111 Upper holder 112 Lower holder 113 First opening 114 First guard section 115 Second opening 116 Second guard section 120 Second holder 121 Recess 130 Third holder 140 Cover section 141 First Cover 142 Second Cover 161 First protector 162 Second protector 163 Fixed hole 321 Thin-walled section 322 Thick wall part 323 Slope 331 First groove (groove) 331b Second groove (groove) D1 First length D2 Second length D3 Third length L1 Dashed line S Gap W1, W2 Length

Claims

1. A conductor; a holder that holds the conductor and has a first space and a second space separated by the conductor; A pusher disposed in the first space; A drive source for moving the pusher from the first space to the second space; Equipped with The conductor is A partition portion separating the first space and the second space; A pair of embedded portions continuous with the partition portion and sandwiching the partition portion therebetween; At least one of the pair of embedded portions is A thin-walled portion continuous with the partition portion; a thick portion that is continuous with the thin portion on the opposite side to the partition portion and is thicker than the thin portion; In a state after the drive source causes the pusher to cut the partition portion of the conductor and move from the first space to the second space, The pusher is A first opposing portion opposing one of the pair of embedded portions; a second opposing portion opposing the other of the pair of embedded portions, When viewed in the moving direction of the pusher, a first length that is the shortest on the outer surface of the pusher connecting the first opposing portion and the second opposing portion is longer than a second length that is the shortest on the outer surface of the pusher connecting the first opposing portion, the bottom of the pusher, and the second opposing portion when viewed in a direction perpendicular to the moving direction of the pusher. Shut-off device.

2. A main surface of the thin portion on the second space side is disposed closer to the first space than a main surface of the thick portion on the second space side. The shutoff device according to claim 1 .

3. The thin portion has a length in a width direction intersecting a direction in which the thin portion extends from the thick portion, the length being smaller than a length of the thick portion in the width direction. The shutoff device according to claim 2.

4. The boundary between the thin portion and the thick portion has an inclined surface. The interrupter device according to any one of claims 1 to 3.

5. A conductor, a holder that holds the conductor and has a first space and a second space separated by the conductor; A pusher disposed in the first space; A drive source for moving the pusher from the first space to the second space; Equipped with The conductor is A partition portion separating the first space and the second space; A pair of embedded portions continuous with the partition portion and sandwiching the partition portion therebetween; At least one of the pair of embedded portions is A thin-walled portion continuous with the partition portion; a thick portion that is continuous with the thin portion on the opposite side to the partition portion and is thicker than the thin portion; In a state after the drive source causes the pusher to cut the partition portion of the conductor and move from the first space to the second space, The pusher is A first opposing portion opposing one of the pair of embedded portions; a second opposing portion opposing the other of the pair of embedded portions, When viewed in the moving direction of the pusher, a first length that is the shortest on the outer surface of the pusher connecting the first opposing portion and the second opposing portion is longer than a third length that is the shortest on the outer surfaces of the pusher and the partition connecting the first opposing portion, a bottom of the partition overlapping the bottom of the pusher, and the second opposing portion when viewed in a direction perpendicular to the moving direction of the pusher. Shut-off device.

6. The partition portion has a groove formed therein that is located on the outer side of the outer surface of the pusher when viewed in the moving direction of the pusher. The interrupter device according to any one of claims 1 to 5.

7. The thin portion has a groove formed therein that runs along the outer surface of the pusher. The interrupter device according to any one of claims 1 to 5.

8. A protrusion is formed on the bottom of the pusher at a position corresponding to the groove, the protrusion protruding laterally. The shutoff device according to claim 7.

9. The length of the protrusion in the moving direction of the pusher is smaller than the thickness of the thin portion. The shutoff device according to claim 8.

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