Patent Application
20240347295
The present invention relates to an electric circuit breaker device.
An electric circuit may be provided with a breaker device that is actuated when an abnormality occurs in a device constituting the electric circuit or when an abnormality occurs in a system in which the electric circuit is mounted, thereby urgently interrupting the continuity of the electric circuit. As one aspect thereof, there has been proposed an electric circuit breaker device that forcibly and physically cuts a conductor piece forming a portion of an electric circuit by moving a projectile at high speed by energy applied from an igniter or the like (see, for example, Patent Document 1). Further, in recent years, electric circuit breaker devices applied to electric vehicles equipped with a high-voltage power source are becoming increasingly important.
The electric circuit breaker device may have a resin housing and a metal holder combined together for weight reduction and size reduction. In this case, in the electric circuit breaker device, the projectile projected during actuation cuts a conductor piece and then is stopped when striking against a portion of the resin housing, but the resin housing is broken during actuation, so that there is a possibility that gas evaporated by arc discharge during cutting leaks. Therefore, it is desirable to suppress generation of gas leakage.
The technology of the present disclosure has been made in view of the above circumstances, and an object thereof is to provide an electric circuit breaker device in which generation of gas leakage after cutting is suppressed.
In order to solve the above problem, an electric circuit breaker device of the present disclosure includes:
According to the present disclosure, an electric circuit breaker device that suppresses generation of gas leakage after actuation can be provided.
An electric circuit breaker device according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that each of the configurations, combinations thereof, and the like in the embodiment are an example, and various additions, omissions, substitutions, and other changes may be made as appropriate without departing from the spirit of the present disclosure. The present disclosure is not limited by the embodiment and is limited only by the claims.
The breaker device 1 includes a housing 10, an igniter 20, a projectile 40, a conductor piece 50, and a coolant material 60. The housing 10 serves as an outer shell member and encloses an accommodating space 13 extending in a direction from a first end portion 11 on an upper end side toward a second end portion 12 on a lower end side. This accommodating space 13 is a space formed linearly, making the projectile 40 movable, and extends along a vertical direction of the breaker device 1. As illustrated in
The housing 10 includes a housing body 100, a top holder 110, and a bottom container 120. The housing body 100 is bonded to the top holder 110 and the bottom container 120, thereby forming the housing 10 that is integral.
The housing body 100 has, for example, a substantially prismatic outer shape. However, the shape of the housing body 100 is not particularly limited. In addition, the housing body 100 includes a cavity portion 145 formed therethrough along the vertical direction. This cavity portion 145 forms a portion of the accommodating space 13. The housing body 100 includes an inner forming portion 131 in contact with the cavity portion 145 and an outer forming portion 132 in contact with the outer circumferential side of the inner forming portion 131 and not in contact with the cavity portion 145. The outer forming portion 132 is disposed on the outer circumferential side of the inner forming portion 131. The inner forming portion 131 and the outer forming portion 132 are integrated. In addition, the housing body 100 has an upper surface 101 on which a flange portion 111 of the top holder 110 is fixed and a lower surface 102 on which a flange portion 121 of the bottom container 120 is fixed. The upper surface 101 extends across the inner forming portion 131 and the outer forming portion 132. The lower surface 102 extends across the inner forming portion 131 and the outer forming portion 132. In the present embodiment, an upper tubular wall 103 having a tubular shape is provided erected upward from the upper surface 101 on the outer circumferential side of the upper surface 101 in the housing body 100. In the present embodiment, the upper tubular wall 103 has a rectangular tubular shape, for example, but may have any other shape. On the outer circumferential side of the lower surface 102 in the housing body 100, a lower tubular wall 104 having a tubular shape is provided suspended downward from the lower surface 102. In the present embodiment, the lower tubular wall 104 has a rectangular tubular shape, for example, but may have any other shape. The upper tubular wall 103 and the lower tubular wall 104 exist in the outer forming portion 132.
The inner forming portion 131 and the outer forming portion 132 of the housing body 100 configured as described above can be formed of an insulating member such as a synthetic resin, for example. The material of the inner forming portion 131 and the material of the outer forming portion 132 may be different materials or the same material. The inner forming portion 131 and the outer forming portion 132 are separately formed (twice formation) regardless of whether they are made of different materials or the same material. By being separately formed, even if a crack is generated in the inner forming portion 131 due to impact or the like, generation of the crack is suppressed in the outer forming portion 132. That is, the crack generated in the inner forming portion 131 can be kept in the inner forming portion 131. In the twice formation, for example, after the inner forming portion 131 is formed with the material of the inner forming portion 131 using a first mold, the inner forming portion 131 is set in a second mold, and the outer forming portion 132 is formed with the material of the outer forming portion 132. Alternatively, the twice formation may be performed, using one mold, in such a manner that after the outer forming portion 132 is formed with a first material, and then the inner forming portion 131 is formed with a second material. The twice formation may be performed by another method. The first material and the second material may be the same or different. For example, the housing body 100 may be formed from nylon, which is a type of polyamide synthetic resin. The inner forming portion 131 may be formed from polycarbonate or the like, for example. The outer forming portion 132 may be formed from, for example, polycarbonate, polyamide, ABS resin, or the like. The outer forming portion 132 is preferably higher in heat resistance temperature than the inner forming portion 131. The inner forming portion 131 is preferably higher in impact resistance than the outer forming portion 132. The impact resistance is durability against an impact received from the outside. The impact resistance is evaluated by an impact value based on a predetermined impact test, for example. The inner forming portion 131 may be formed separately by being divided into an upper forming portion disposed above (the top holder 110 side and the igniter 20 side) and a lower forming portion disposed below (the bottom container 120 side and a movement destination side of the projectile 40). Since the upper forming portion and the lower forming portion are separately formed, propagation of a crack generated in the upper part (the upper forming portion) of the inner forming portion 131 and generation of a crack in the lower part (the lower forming portion) of the inner forming portion 131 are suppressed. Alternatively, the outer forming portion 132 may be separately formed by being divided into the upper forming portion disposed above and the lower forming portion disposed below. That is, the housing body 100 may be formed three or more times. Since the housing body 100 is formed a plurality of times, generation of a void can be suppressed. A part (resin interface) between the inner forming portion 131 and the outer forming portion 132 may be welded. A part (resin interface) between the inner forming portion 131 and the outer forming portion 132 may be sealed with a sheet-like gasket.
Next, the top holder 110 will be described. The top holder 110 is, for example, a cylindrical member having a stepped cylindrical tubular shape with a hollow inside. The top holder 110 includes a small diameter cylinder portion 112 positioned on the upper side (first end portion 11 side), a large diameter cylinder portion 113 positioned on the lower side, a connection portion 114 connecting these, and the flange portion 111 extending outward from a lower end of the large diameter cylinder portion 113. For example, the small diameter cylinder portion 112 and the large diameter cylinder portion 113 are coaxially disposed, and the large diameter cylinder portion 113 has a diameter slightly larger than that of the small diameter cylinder portion 112.
The contour of the flange portion 111 in the top holder 110 has a substantially quadrangular shape that fits inside the upper tubular wall 103 in the housing body 100. The flange portion 111 is provided, extending in a vertical direction, with a bolt passing hole (not illustrated) through which a fastening bolt passes.
The cavity portion formed inside the small diameter cylinder portion 112 in the top holder 110 functions as an accommodating space for accommodating a portion of the igniter 20 as illustrated in
Next, the bottom container 120 will be described. The bottom container 120 has a substantially tubular bottomed shape with a hollow inside, and includes a side wall portion 122, a bottom wall portion 123 connected to a lower end of the side wall portion 122, and a flange portion 121 connected to an upper end of the side wall portion 122. The side wall portion 122 has, for example, a cylindrical tubular shape. The flange portion 121 extends outward from the upper end of the side wall portion 122. The contour of the flange portion 121 in the bottom container 120 has a substantially quadrangular shape that fits inside the lower tubular wall 104 in the housing body 100. The flange portion 121 is provided, extending in a vertical direction, with a bolt passing hole (not illustrated) through which a fastening bolt passes.
Note that the above aspect regarding the shape of the bottom container 120 is an example, and other shapes may be adopted. Further, the cavity portion formed inside the bottom container 120 communicates with the housing body 100 positioned above, and forms a portion of the accommodating space 13. The bottom container 120 configured as described above can be formed from an appropriate metal member, such as stainless steel or aluminum, having excellent strength and durability, for example. However, a material for forming the bottom container 120 is not particularly limited. Further, the bottom container 120 may have a multilayer structure. For example, in the bottom container 120, an exterior portion facing the outside may be formed from an appropriate metal member, such as stainless steel or aluminum, having excellent strength and durability, and an interior portion facing the accommodating space 13 side may be formed from an insulating member such as a synthetic resin. Of course, the entire bottom container 120 may be formed from an insulating member.
As described above, the housing 10 in the present embodiment is configured by integrally assembling, in the vertical direction, the housing body 100, the top holder 110, and the bottom container 120, which are integrally assembled. In the process of this assembly, the conductor piece 50 is disposed through the inside of the housing body 100. For example, the conductor piece 50 is passed through the conductor piece holding holes 105A and 105B of the housing body 100, and the conductor piece is disposed across the cavity portion 145. In this state, the flange portion 111 of the top holder 110 is inserted through inside the upper tubular wall 103 in the housing body 100 to dispose the top holder 110 on the housing body 100, and the flange portion 121 of the bottom container 120 is inserted through inside the lower tubular wall 104 in the housing body 100 to dispose the bottom container 120 under the housing body 100. Then, bolts are passed through the bolt passing holes of the top holder 110, the housing body 100, and the bottom container 120 to fasten the respective portions. This fastening is not limited to the bolt, and may be performed by any other fastening mechanism such as a rivet.
In addition, each portion may be coupled in a state where a sealant is applied between the top holder 110 and the housing body 100, between the housing body 100 and the conductor piece 50, and between the housing body 100 and the bottom container 120. Thereby, airtightness of this tubular accommodating space 13 formed in the housing 10 can be increased. The airtightness of the accommodating space 13 may be increased by interposing a packing or a gasket between the respective portions in place of the sealant or in combination with a sealant. This accommodating space 13 accommodates the igniter 20, the projectile 40, a cutoff portion 53 of the conductor piece 50, the coolant material 60, and the like described in detail below.
Next, the igniter 20 will be described. The igniter 20 is an electric igniter that includes an ignition portion 21 with an ignition charge, and an igniter body 22 including a pair of conduction pins (not illustrated) connected to the ignition portion 21. The igniter body 22 is surrounded by an insulating resin, for example. Further, tip end sides of the pair of conduction pins in the igniter body 22 are exposed to the outside, and are connected to a power source when the breaker device 1 is used.
The igniter body 22 includes a body portion 221 having a substantially circular columnar shape and accommodated inside the small diameter cylinder portion 112 in the top holder 110, and a connector portion 222 positioned on the body portion 221. The igniter body 22 is fixed to the small diameter cylinder portion 112 by press-fitting, for example, the body portion 221 to an inner circumferential surface of the small diameter cylinder portion 112. Further, a constricted portion having an outer circumferential surface recessed as compared with other locations is annularly formed along a circumferential direction of the body portion 221 at an axially intermediate portion of the body portion 221. An O-ring 223 is fitted into this constricted portion. The O-ring 223 is formed from, for example, rubber (silicone rubber, for example) or a synthetic resin, and functions to increase airtightness between the inner circumferential surface in the small diameter cylinder portion 112 and the body portion 221.
The connector portion 222 in the igniter 20 is disposed protruding to the outside through an opening 112A formed at an upper end of the small diameter cylinder portion 112. The connector portion 222 has, for example, a cylindrical tubular shape covering sides of the conduction pins, allowing connection with a connector of a power source.
As illustrated in
In actuation of the igniter 20, when an actuating current for igniting the ignition charge is supplied from the power source to the conduction pins, the bridge wire in the ignition portion 21 generates heat, and as a result, the ignition charge in the igniter cup is ignited and burns, generating a combustion gas. Then, the pressure in the igniter cup increases along with the combustion of the ignition charge in the igniter cup of the ignition portion 21, a rupture surface 21A of the igniter cup ruptures, and the combustion gas is discharged from the igniter cup into the accommodating space 13. More specifically, the combustion gas from the igniter cup is discharged into a recess 411 in a piston portion 41 described later of the projectile 40 disposed in the accommodating space 13. Thereby, the projectile 40 is projected downward from the initial position in
Next, the conductor piece 50 will be described.
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
The conductor piece 50 is cut at a position overlapping an inner surface (inner wall surface) of the inner wall defining the cavity portion 145 of the housing body 100, that is, a position overlapping an outer circumferential surface of the rod portion 42, and the cutoff portion 53 is cut off.
Here, various forms of the conductor piece 50 can be adopted, and a shape thereof is not particularly limited. In the example illustrated in
Next, the coolant material 60 disposed in the accommodating space 13 in the housing 10 will be described. Here, as illustrated in
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 cooling 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 in the breaker device 1 is a space for receiving the cutoff portion 53 cut off from the first connection end portion 51 and the second connection end portion 52 of the conductor piece 50 by the projectile 40, and at the same time, has a meaning as a space for effectively extinguishing an 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.
Next, the projectile 40 will be described.
Further, the recess 411 having a circular columnar shape, for example, is formed in an upper surface of the piston portion 41. This recess 411 receives the ignition portion 21. A bottom surface of the recess 411 is formed as a pressure receiving surface 411A that receives energy received from the igniter 20 during actuation of the igniter 20. Further, a constricted portion having an outer circumferential surface recessed as compared with other locations is annularly formed along a circumferential direction of the piston portion 41 at an axially intermediate portion of the piston portion 41. An O-ring 43 is fitted into this constricted portion. The O-ring 43 is formed from, for example, rubber (silicone rubber, for example) or a synthetic resin, and functions to increase airtightness between an inner circumferential surface in the large diameter cylinder portion 113 and the piston portion 41.
The rod portion 42 of the projectile 40 is a rod-shaped member having an outer circumferential surface smaller in diameter than the piston portion 41 and extending along the extending direction of the accommodating space 13, for example, and is integrally connected to a lower end side of the piston portion 41. When the igniter 20 is actuated, the rod portion 42 moves along the extending direction of the accommodating space 13 and is inserted into the cavity portion 145 of the housing body 100. A lower end surface of the rod portion 42 is formed as a cutoff surface 420 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, an elliptic cylinder, or a prism, for example. Note that, in the initial position of the projectile 40 illustrated in
In the projectile 40 configured as described above, the projectile 40 is projected from the initial position illustrated in
Next, operation content when the breaker device 1 is actuated to interrupt the electric circuit will be described. As described above.
Furthermore, the breaker device 1 according to the embodiment further includes an abnormality detection sensor (not illustrated) that detects 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) that controls the actuation of the igniter 20. In addition to the current flowing through the conductor piece 50, the abnormality detection sensor may be able to detect 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 pins 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 pins 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.
Then, as illustrated in the lower part of
The breaker device 1 in the embodiment includes the housing body 100 including the inner forming portion 131 in contact with the cavity portion 145 and the outer forming portion 132 outside the inner forming portion 131. Since the housing body 100 has the inner forming portion 131 and the outer forming portion 132 that are separately formed, even if a crack is generated in the inner forming portion 131 when receiving an impact due to piston actuation, generation of the crack can be suppressed in the outer forming portion 132. Since no crack is generated in the outer forming portion 132, the internal gas can be suppressed from leaking to the outside.
While the embodiment of the electric circuit breaker device according to the present disclosure has been described above, each of the aspects disclosed in the present specification can be combined with any other feature disclosed in the present specification.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-169081 | Oct 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/038221 | 10/13/2022 | WO |
