42 is formed as a cutoff surface 421 for cutting off the cutoff portion 53 from the conductor piece 50 during actuation of the breaker device 1. Note that although the rod portion 42 in the present embodiment has a substantially cylindrical tubular shape, the shape thereof is not particularly limited, and can be changed in accordance with the shape and size of the cutoff portion 53 to be cut off from the conductor piece 50 during actuation of the breaker device 1. The rod portion 42 may have a columnar shape such as a cylinder or a prism, for example. Note that, in an initial position of the projectile 40 illustrated in FIG. 1, a region on a tip end side including the cutoff surface 421 in the rod portion 42 of the projectile 40 is positioned in the cavity portion (forming a portion of the accommodating space 13) of the housing body 100. The diameter of the rod portion 42 is slightly smaller than the inner diameter of an inner circumferential surface of the housing body 100, for example, and the outer circumferential surface of the rod portion 42 is guided along the inner circumferential surface when the projectile 40 is projected.

As described in detail later, the projectile 40 configured as described above is projected from the initial position illustrated in FIG. 1 when the upper surface of the piston portion 41 including the pressure receiving surface 411A receives the energy from the igniter 20 during actuation of the igniter 20, and moves at high speed toward the second end portion 12 side (downward) along the accommodating space 13. Specifically, as illustrated in FIG. 1, the piston portion 41 of the projectile 40 is accommodated inside the large diameter cylinder portion 113 in the top holder 110, and is slidable in the axial direction along an inner wall surface of the large diameter cylinder portion 113. In the present embodiment, the piston portion 41 of the projectile 40 has a substantially cylindrical shape, but the shape thereof is not particularly limited. As the outer shape of the piston portion 41, an appropriate shape and size can be adopted in accordance with the shape and size of the inner wall surface of the large diameter cylinder portion 113.

Conductor Piece

Next, the conductor piece 50 will be described. FIG. 2 is a top view of the conductor piece 50 according to the embodiment. The conductor piece 50 is a metal body having conductivity that constitutes a portion of the components of the breaker device 1 and, when the breaker device 1 is attached to a predetermined electric circuit, forms a portion of the electric circuit, and may be referred to as a bus bar. The conductor piece 50 can be formed from a metal such as copper (Cu), for example. However, the conductor piece 50 may be formed from a metal other than copper, or may be formed from an alloy of copper and another metal. Note that examples of metals other than copper included in the conductor piece 50 include manganese (Mn), nickel (Ni), and platinum (Pt).

In one aspect illustrated in FIG. 2, the conductor piece 50 is formed as an elongated flat plate piece as a whole, and includes a first connecting end portion 51 and a second connecting end portion 52 on both end sides, and the cutoff portion 53 positioned in an intermediate portion therebetween. Connection holes 51A, 52A are provided in the first connecting end portion 51 and the second connecting end portion 52 of the conductor piece 50, respectively. These connection holes 51A, 52A are used to connect with other conductors (lead wires, for example) in the electric circuit. Note that in FIG. 1, the connection holes 51A and 52A in the conductor piece 50 are not illustrated. The cutoff portion 53 of the conductor piece 50 is a portion forcibly and physically cut by the rod portion 42 of the projectile 40 and is cut off from the first connecting end portion 51 and the second connecting end portion 52 when an abnormality such as excessive current occurs in the electric circuit to which the breaker device 1 is applied. Notches (slits) 54 are formed at both ends of the cutoff portion 53 of the conductor piece 50, making it easy to cut and cut off the cutoff portion 53.

Here, various forms of the conductor piece 50 can be adopted, and a shape thereof is not particularly limited. While, in the example illustrated in FIG. 2, surfaces of the first connecting end portion 51, the second connecting end portion 52, and the cutoff portion 53 form the same surface, the form is not limited thereto. For example, the conductor piece 50 may be connected such that the cutoff portion 53 is orthogonal to or inclined relative to the first connecting end portion 51 and the second connecting end portion 52. Further, the planar shape of the cutoff portion 53 of the conductor piece 50 is not particularly limited, either. Of course, the shapes of the first connecting end portion 51 and the second connecting end portion 52 of the conductor piece 50 are not particularly limited, either. Further, the notches 54 in the conductor piece 50 can be omitted as appropriate.

Here, a pair of conductor piece holding holes 105A and 105B are formed in the housing body 100 according to the embodiment. The pair of conductor piece holding holes 105A and 105B extend in a transverse cross-sectional direction orthogonal to the vertical direction (axial direction) of the housing body 100. More specifically, the pair of conductor piece holding holes 105A and 105B extend in a straight line with the cavity portion (accommodating space 13) of the housing body 100 interposed therebetween. The conductor piece 50 configured as described above is held in the housing body 100 in a state of being inserted through the pair of conductor piece holding holes 105A and 105B formed in the housing body 100. In the example illustrated in FIG. 1, the first connecting end portion 51 of the conductor piece 50 is held in a state of being inserted through the conductor piece holding hole 105A, and the second connecting end portion 52 is held in a state of being inserted through the conductor piece holding hole 105B. In this state, the cutoff portion 53 of the conductor piece 50 is positioned in the cavity portion (accommodating space 13) of the housing body 100. As described above, the conductor piece 50 attached to the housing body 100 is held orthogonally to the extending direction (axial direction) of the accommodating space 13 with the cutoff portion 53 crossing the accommodating space 13. Note that reference sign L1 illustrated in FIG. 2 denotes an outer circumferential position of the rod portion 42 positioned above the conductor piece 50 in a state of being attached to the housing body 100 of the breaker device 1. In the present embodiment, the conductor piece 50 is installed with the outer circumferential position L1 of the rod portion 42 substantially overlapping the positions of the notches 54 positioned at both ends of the cutoff portion 53. In the present embodiment, for example, since a transverse cross-sectional area of the accommodating space 13 is larger than a transverse cross-sectional area of the cutoff portion 53, a gap is formed on the side of the cutoff portion 53.

Coolant Material

Next, the coolant material 60 disposed in the accommodating space 13 in the housing 10 will be described. Here, as illustrated in FIG. 1, prior to actuation of the breaker device 1 (igniter 20), the cutoff portion 53 of the conductor piece 50 in a state of being held in the pair of conductor piece holding holes 105A and 105B in the housing body 100 is horizontally laid crossing the accommodating space 13 of the housing 10. Hereinafter, within the accommodating space 13 of the housing 10 separated by the cutoff portion 53 of the conductor piece 50, a region (space) in which the projectile 40 is disposed is referred to as a “projectile initial arrangement region R1”, and a region (space) positioned on the opposite side of the projectile 40 is referred to as an “arc-extinguishing region R2”. Note that as described above, since the gap is formed on the side of the cutoff portion 53 disposed crossing the accommodating space 13, the projectile initial arrangement region R1 and the arc-extinguishing region R2 are not completely isolated from each other by the cutoff portion 53, but communicate with each other. Of course, depending on the shape and size of the cutoff portion 53, the projectile initial arrangement region R1 and the arc-extinguishing region R2 may be completely isolated from each other by the cutoff portion 53.

The arc-extinguishing region R2 of the accommodating space 13 is a region (space) for receiving the cutoff portion 53 cut off by the rod portion 42 of the projectile 40 projected during actuation of the breaker device 1 (igniter 20). In this arc-extinguishing region R2, the coolant material 60 as an arc-extinguishing material is disposed. The coolant material 60 is a coolant material for removing thermal energy of the arc generated and the cutoff portion 53 when the projectile 40 cuts off the cutoff portion 53 of the conductor piece 50, and cools the arc and the cutoff portion 53, thereby suppressing arc generation during cutting off of a current or thereby extinguishing (eliminating) the generated arc.

The arc-extinguishing region R2 of the breaker device 1 has significance as a space for receiving the cutoff portion 53 cut off from the first connecting end portion 51 and the second connecting end portion 52 of the conductor piece 50 by the projectile 40 and, at the same time, as a space for effectively extinguishing the arc generated when the projectile 40 cuts off the cutoff portion 53. Then, in order to effectively extinguish the arc generated when the cutoff portion 53 is cut off from the conductor piece 50, the coolant material 60 is disposed as an arc-extinguishing material in the arc-extinguishing region R2.

As one aspect of the embodiment, the coolant material 60 is solid. As one aspect of the embodiment, the coolant material 60 is formed from a shape retaining body. The shape retaining body herein is, for example, a material that can keep a constant shape when no external force is applied and can hold the integrity (does not come apart), even if deformation can occur, when an external force is applied. For example, examples of the shape retaining body include a fibrous body formed into a desired shape. In the present embodiment, the coolant material 60 is formed from a metal fiber that is a shape retaining body. Here, examples of the metal fiber forming the coolant material 60 include an aspect in which at least any one of steel wool or copper wool is included. However, the above aspects in the coolant material 60 are examples, and the coolant material 60 is not limited to the above aspects.

The coolant material 60 is formed into a substantially disk shape, for example, and is disposed at a bottom portion of the bottom container 120.

Resin Material

Next, the resin material 70 will be described. The resin material 70 is disposed in the accommodating space 13 of the housing 10. The resin material 70 of the present embodiment is disposed in the arc-extinguishing region R2. When the igniter 20 is actuated, the resin material is modified by the heat of the arc generated and the cutoff portion 53 when the projectile 40 cuts off the cutoff portion 53 of the conductor piece 50. This modification consumes thermal energy, thereby contributing to extinguishing (eliminating) of the arc. As described above, similar to the coolant material 60, the resin material 70 functions as an arc-extinguishing material. Note that the resin material 70 is modified mainly by the heat of the arc, but other than this, the resin material 70 is also affected by the heat generated when the cutoff portion 53 is cut off and the heat such as combustion heat of the ignition charge. The heat received from ignition of the ignition charge to completion of arc-extinguishing is referred to as heat associated with actuation of the igniter 20.

The resin material 70 of the present embodiment is a synthetic resin including silicone. Note that the resin material is not limited to silicone, and may be a material using another resin such as polyurethane, polyethylene, polypropylene, polyamide, or nitrile rubber. The resin material 70 is only required to be a material at least a portion of which is modified by heat, and may be made of a composite material including glass, a ceramic filler, or the like.

The resin material 70 is formed in a ring shape or an arc shape, and is provided along an inner wall of the side wall portion 122 from an upper surface of the coolant material 60 to an upper end of the bottom container 120. The resin material 70 is not limited to a solid member formed in a predetermined shape, and may be a gel-like material or a highly viscous liquid material applied to a wall surface in the accommodating space 13 to be used as in FIG. 1. Further, the resin material 70 may be fixedly provided on the wall surface by applying a synthetic resin melted with an organic solvent such as toluene to the wall surface in the accommodating space 13 and then volatilizing the organic solvent.

Operation

Next, operation content when the breaker device 1 is actuated to interrupt the electric circuit will be described. As described above, FIG. 1 illustrates a state of the breaker device 1 prior to actuation (hereinafter also referred to as the “pre-actuation initial state”). In this pre-actuation initial state, in the projectile 40 in the breaker device 1, the piston portion 41 is positioned on the first end portion 11 side (upper end side) in the accommodating space 13, and the cutoff surface 421 formed at the lower end of the rod portion 42 is set at an initial position positioned on the upper surface of the cutoff portion 53 in the conductor piece 50.

Furthermore, the breaker device 1 according to the embodiment further includes an abnormality detection sensor (not illustrated) configured to detect an abnormal state of a device (such as a vehicle, a power generation facility, or a power storage facility) to which an electric circuit to be cut off is connected, and a control unit (not illustrated) configured to control the actuation of the igniter 20. In addition to the current flowing through the conductor piece 50, the abnormality detection sensor may be capable of detecting an abnormal state on the basis of a voltage or a temperature of the conductor piece 50. Further, the abnormality detection sensor may be, for example, an impact sensor, a temperature sensor, an acceleration sensor, a vibration sensor, or the like, and may detect an abnormal state such as an accident or fire on the basis of an impact, a temperature, acceleration, or vibration in a device such as a vehicle. The control unit of the breaker device 1 is a computer capable of performing a predetermined function by executing a predetermined control program, for example. The predetermined function of the control unit may be realized by corresponding hardware. Then, when excessive current flows through the conductor piece 50 forming a portion of the electric circuit to which the breaker device 1 is applied, the abnormal current is detected by the abnormality detection sensor. Abnormality information regarding the detected abnormal current is passed from the abnormality detection sensor to the control unit. For example, the control unit is energized from an external power source (not illustrated) connected to the conduction pin of the igniter 20 and actuates the igniter 20 based on the current value detected by the abnormality detection sensor. Here, the abnormal current may be a current value that exceeds a predetermined threshold value set for protection of a predetermined electric circuit. Note that the abnormality detection sensor and the control unit described above need not be included in the components of the breaker device 1, and may be included in a device separate from the breaker device 1, for example. Further, the abnormality detection sensor and the control unit are not essential components of the breaker device 1.

For example, when an abnormal current of the electric circuit is detected by an abnormality detection sensor that detects an abnormal current of the electric circuit, the control unit of the breaker device 1 actuates the igniter 20. That is, an actuating current is supplied from the external power source (not illustrated) to the conduction pin of the igniter 20, and as a result, the ignition charge in the ignition portion 21 is ignited and burns, generating a combustion gas. Then, the rupture surface 21A ruptures due to rise in pressure in the ignition portion 21, and the combustion gas of the ignition charge is discharged from the inside of the ignition portion 21 into the accommodating space 13.

Here, the ignition portion 21 of the igniter 20 is received in the recess 411 of the piston portion 41, and the rupture surface 21A of the ignition portion 21 is disposed facing the pressure receiving surface 411A of the recess 411 in the projectile 40. Therefore, the combustion gas from the ignition portion 21 is discharged to the recess 411, and the pressure (combustion energy) of the combustion gas is transmitted to the upper surface of the piston portion 41 including the pressure receiving surface 411A. As a result, the projectile 40 moves downward in the accommodating space 13 in the extending direction (axial direction) of the accommodating space 13.

FIGS. 3A and 3B are views illustrating actuation situations of the breaker device 1 according to the embodiment. FIG. 3A illustrates a situation in the middle of actuation of the breaker device 1, and FIG. 3B illustrates a situation in which the actuation of the breaker device 1 is completed. As described above, upon actuation of the igniter 20, the projectile 40 having received the pressure (combustion energy) of the combustion gas of the ignition charge is vigorously pushed downward. As a result, the cutoff surface 421 formed on the lower end side of the rod portion 42 pressingly cuts, by shearing, the boundary portions between the first connecting end portion 51 and the cutoff portion 53 and between the second connecting end portion 52 and the cutoff portion 53 in the conductor piece 50. As a result, the cutoff portion 53 is cut off from the conductor piece 50. Note that as long as the projectile 40 can be moved smoothly in the extending direction (axial direction) of the accommodating space 13 when the igniter 20 is actuated, the shape and the dimensions of the projectile 40 can be freely determined, and the outer diameter of the piston portion 41 of the projectile 40 may be set to a dimension equal to the inner diameter of the large diameter cylinder portion 113 in the top holder 110, for example.

Then, as illustrated in FIG. 3B, the projectile 40 moves downward in the extending direction (axial direction) of the accommodating space 13 by a predetermined stroke until the lower end surface of the piston portion 41 abuts (collides with) the upper surface 101 of the housing body 100. Then, in this state, the cutoff portion 53, which has been cut off from the conductor piece 50 by the rod portion 42 of the projectile 40, is received in the arc-extinguishing region R2 where the coolant material 60 and the resin material 70 are disposed. As a result, the first connecting end portion 51 and the second connecting end portion 52 positioned on both ends of the conductor piece 50 are electrically disconnected, and the predetermined electric circuit to which the breaker device 1 is applied is forcibly interrupted.

In the breaker device 1 of the embodiment, the coolant material 60 is disposed in the arc-extinguishing region R2. Therefore, the cutoff portion 53 after being cut off that has been received in the arc-extinguishing region R2 can be rapidly cooled by the coolant material 60. Thus, when the cutoff portion 53 is cut off from the conductor piece 50 constituting a portion of the predetermined electric circuit by the projectile 40, even in a case where an arc is generated at the cut surface of the cutoff portion 53 of the conductor piece 50, the generated arc can be quickly and effectively extinguished.

Furthermore, in the breaker device 1, the resin material 70 as an arc-extinguishing material is disposed between the coolant material 60 and the cutoff portion 53 in the arc-extinguishing region R2. Thus, immediately after the rod portion 42 cuts off the cutoff portion 53 from the conductor piece 50, that is, when an arc is generated by the cutting off, the resin material 70 is modified by the heat of this arc, and this modification consumes the heat of the arc, whereby the arc can be quickly and effectively extinguished. The resin material 70 is made of a material that is easily modified, such as being decomposed or volatilized, by heat as compared with other resin materials such as the housing 10 and the projectile 40, and this modification can effectively consume the heat of the arc. Further, in the resin material 70 of the present embodiment, a component such as silica generated by thermal decomposition exhibits a high resistance value, and as this component scatters, the resin material 70 contributes to improving the insulation property after cutting.

As described above, according to the breaker device 1 of the present embodiment, the cutoff portion 53 is cooled by the coolant material 60 and the resin material 70, and arc generation can be effectively suppressed. As a result, it is possible to quickly interrupt the electric circuit to which the breaker device 1 is applied in a case where an abnormality is detected in the electric circuit, or the like. That is, by effectively suppressing delay in extinguishing of the arc generated when the electric circuit is interrupted, it is possible to suppress delay in interruption of the electric circuit. Further, effectively cooling the heat of the arc by the coolant material 60 and the resin material 70 can suppress evaporation of the conductor piece 50 that has been cut off, and achieve a sufficiently high insulation resistance value after cutting. Furthermore, according to the breaker device 1, it is possible to suitably suppress the generation of a large spark or flame or the generation of a loud impact sound when the electric circuit is interrupted. Further, damage to the housing 10 and the like of the breaker device 1 caused by these can also be suppressed.

Modification 1

For the breaker device 1 according to the embodiment, various modifications can be adopted. For example, the shape, position, range, and the like of the coolant material 60 disposed in the arc-extinguishing region R2 of the accommodating space 13 can be changed as appropriate. For example, FIG. 4 is a view illustrating an internal structure of a breaker device 1A according to a modification 1. The breaker device 1A of the present modification 1 has a configuration in which a resin material 71 is disposed in the projectile initial arrangement region R1 in addition to the configuration of the breaker device 1 illustrated in FIG. 1. Note that since the other configurations are the same, the description thereof will be omitted.

The resin material 71 is disposed between the piston portion 41 and the cutoff portion 53, and between an inner wall of the top holder 110 and the rod portion 42 prior to actuation of the igniter 20. Thus, when the projectile 40 is projected upon actuation of the igniter 20, a portion of the resin material 71 on the rod portion 42 side moves to the cutoff portion 53 side together with the rod portion 42 due to friction with the rod portion 42, and is further crushed by the piston portion 41 and moves to the cutoff portion 53 side. Then, when the rod portion 42 cuts off the cutoff portion 53 and an arc is generated, the resin material 71 is modified by the heat of the arc, thereby removing the heat of the arc to cool the arc.

Accordingly, as illustrated in FIG. 3A, the cutoff portion 53 can be cooled by the resin material 71 even at the moment when the cutoff portion 53 is cut off from the conductor piece 50 by the cutoff surface 421 of the rod portion 42 and immediately thereafter, that is, in a transient state from the moment when the cutoff portion 53 is cut off from the conductor piece 50 to when the cutoff portion 53 comes into contact with the coolant material 60 disposed in the arc-extinguishing region R2. This makes it possible to suitably suppress the generation of an arc at the cut surface of the cutoff portion 53 in the transient state at the moment when the cutoff portion 53 is cut off from the conductor piece 50 and immediately thereafter.

Modification 2

FIG. 5 is a view illustrating an internal structure of a breaker device 1B according to a modification 2. The breaker device 1B of the present modification 2 has a configuration in which the resin material 70 is removed from the configuration of the breaker device 1A illustrated in FIG. 4. Note that since the other configurations are the same, the description thereof will be omitted. Even with the configuration in which the resin material 70 is removed as described above, since the resin material 71 cools the cutoff portion 53, arc generation can be suppressed.

Modification 3

FIG. 6 is a view illustrating an internal structure of a breaker device 1C according to a modification 3. FIG. 7 is an explanatory view of a coolant material 61 and a resin material 74 according to the modification 3. The breaker device IC of the present modification 3 has a configuration in which the resin material in the arc-extinguishing region R2 is impregnated in the coolant material 61 as compared with the configuration of the breaker device 1A illustrated in FIG. 4. Note that since the other configurations are the same, the description thereof will be omitted.

In the present modification 3, the coolant material 61 provided in the arc-extinguishing region R2 is formed in a bowl shape along an inner wall of the bottom container 120 using a metal fiber such as steel wool. The upper half of FIG. 7 schematically illustrates a cross section of the coolant material 61 formed from a metal fiber. Then, using a resin material that is liquid in an initial state and is solidified upon reaction with air, heat, ultraviolet rays, or the like, the resin material in a liquid state is impregnated in a circumferential wall 61W of the coolant material 61 and is then solidified, thereby forming the resin material 74 in the circumferential wall 61W portion of the coolant material 61 as illustrated in the lower half of FIG. 7. Even with the configuration in which the resin material 74 is provided impregnated in the coolant material 61 as described above, the cutoff portion 53 after being cut off is cooled by the resin material 74, whereby the arc can be quickly and effectively extinguished. Note that solidification of the resin material 74 is not essential as long as the resin material has viscosity even in a liquid state, for example, and is held at a predetermined position in a state of being impregnated in the coolant material 61.

Electric Circuit Interruption Test

Next, an electric circuit interruption test performed on the breaker devices 1 and 1A will be described. FIG. 8 is a view schematically illustrating a testing device used in the electric circuit interruption test. Reference sign 1000 denotes a power source, reference sign 2000 denotes an insulation resistance meter, and reference sign 3000 denotes an actuation power source. Further, reference sign 4000 denotes wiring for forming an electric circuit EC in cooperation with the conductor piece 50