BREAKER DEVICE

This breaker device includes: a casing; an igniter disposed in the casing; a conductor including a separating portion disposed below the igniter; and a pusher located between the separating portion and the igniter and configured to move together with the separating portion from a first position to a second position located below the first position. The casing includes: a first casing made of a metal, including a first fixing portion, and configured to house the igniter and the pusher located at the first position; and a second casing made of a metal, including a second fixing portion, and configured to house the pusher that has moved to the second position and the separating portion that has moved downward together with the pusher. The first fixing portion and the second fixing portion overlap each other, come into contact with each other, and are fixed to each other.

TECHNICAL FIELD

The present disclosure relates to breaker devices.

BACKGROUND ART

There are conventionally known breaker devices that, when in use, are connected to an electrical circuit. Such a breaker device includes: a casing; and a pusher that is disposed in the casing and moves from a first position to a second position with gas generated by an igniter when turned ON, and the pusher moving from the first position to the second position splits or cuts a conductor, thus interrupting an electrical path. The casing is formed by fixing a first casing and a second casing. For example, Patent Literature (PTL 1) discloses a breaker device in which two flanges (flange portions) that are formed on two respective cover members (casings) and between which a spacer made of a metal is disposed are joined together using screws.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

In the breaker device disclosed in PTL 1, the flanges for fixing the first casing and the second casing need to be provided, leading to an increase in the size of the breaker device, which is problematic.

Thus, the present disclosure provides a breaker device that is smaller than a conventional breaker device.

A breaker device according to one aspect of the present disclosure includes: a casing; an igniter disposed in the casing; a conductor including a separating portion disposed below the igniter; and a pusher located between the separating portion and the igniter and configured to move together with the separating portion from a first position to a second position located below the first position, wherein the casing includes: a first casing that is made of a metal, includes a first fixing portion, and is configured to house the igniter and the pusher located at the first position; and a second casing that is made of a metal, includes a second fixing portion, and is configured to house the pusher that has moved to the second position and the separating portion that has moved downward together with the pusher, and the first fixing portion and the second fixing portion overlap each other, come into contact with each other, and are fixed to each other.

According to one aspect of the present disclosure, it is possible to provide a breaker device that is smaller than a conventional breaker device.

DESCRIPTION OF EMBODIMENTS

A breaker device according to one aspect of the present disclosure includes: a casing; an igniter disposed in the casing; a conductor including a separating portion disposed below the igniter; and a pusher located between the separating portion and the igniter and configured to move together with the separating portion from a first position to a second position located below the first position, wherein the casing includes: a first casing that is made of a metal, includes a first fixing portion, and is configured to house the igniter and the pusher located at the first position; and a second casing that is made of a metal, includes a second fixing portion, and is configured to house the pusher that has moved to the second position and the separating portion that has moved downward together with the pusher, and the first fixing portion and the second fixing portion overlap each other, come into contact with each other, and are fixed to each other.

With this configuration, the first casing and the second casing are fixed in contact with each other at overlapping portions, and thus there is no need to provide flanges for fixing with screws on the first casing and the second casing, resulting in a breaker device that is smaller than a conventional breaker device.

It is preferable that the first casing include: a first body portion configured to house the igniter and the pusher located at the first position; and a first fixing portion that protrudes downward from the first body portion, and the second casing include: a second body portion located below the first body portion and configured to house the pusher that has moved to the second position and the separating portion that has moved downward together with the pusher; and a second fixing portion that protrudes upward from the second body portion.

With this configuration, the fixing portions protruding upward and downward are fixed to each other, resulting in an even smaller breaker device.

It is preferable that the first casing further include a third fixing portion that protrudes downward from the first body portion and opposes the first fixing portion, and the second casing further include a fourth fixing portion that protrudes upward from the second body portion, opposes the second fixing portion, overlaps the third fixing portion, comes into contact with the third fixing portion, and is fixed to the third fixing portion.

With this configuration, fixing is achieved in an area where the third fixing portion and the fourth fixing portion overlap in addition to an area where the first fixing portion and the second fixing portion overlap, making it easy to distribute stress imposed on the second casing to the first casing. Thus, it is possible to improve the strength of the breaker device.

It is preferable that the breaker device further include: a resin member in which the conductor is embedded, the resin member including an inner side wall facing an outer side wall of the pusher and a first outer side wall disposed in the casing and covered by the first casing; and a first elastic member disposed between the first casing and the first outer side wall of the resin member.

With this configuration, when the internal pressure in the casing increases due to, for example, gas generated by the igniter or an electric arc generated when the pusher cuts off the separating portion, the resin member is pressed outward and the first casing is pressed upward due to the increase in pressure; as a result, with the resin member and the first casing, the first elastic member is further pressed compared to the initial state. Thus, it is possible to reduce leakage of high-temperature gas to the outside of the breaker device through the spacing between the resin member and the first casing.

It is preferable that the breaker device further include: a resin member in which the conductor is embedded, the resin member including a second outer side wall disposed in the casing and covered by the second casing; and a second elastic member disposed between the second casing and the second outer side wall of the resin member.

With this configuration, when the internal pressure in the casing increases due to, for example, gas generated by the igniter or an electric arc generated when the pusher cuts off the separating portion, the resin member is pressed outward and the second casing is pressed downward due to the increase in pressure; as a result, with the resin member and the second casing, the second elastic member is further pressed compared to the initial state. Thus, it is possible to reduce leakage of high-temperature gas to the outside of the breaker device through the spacing between the resin member and the second casing.

Note that the first fixing portion described above may be disposed outward of the second fixing portion.

With this configuration, the breaker device configured so that the first fixing portion is disposed outward of the second fixing portion can be made smaller than a conventional breaker device.

Note that the first fixing portion described above may be disposed inward of the second fixing portion.

With this configuration, the breaker device configured so that the first fixing portion is disposed inward of the second fixing portion can be made smaller than a conventional breaker device.

Note that in the above-described breaker device, after the pusher cuts off the separating portion from the conductor, the separating portion may move downward together with the pusher.

Hereinafter, an exemplary embodiment will be specifically described with reference to the drawings.

Note that each exemplary embodiment described below shows a general or specific example. The numerical values, shapes, structural elements, the arrangement and connection of the structural elements, steps (manufacturing steps), the processing order of the steps (manufacturing steps), etc., shown in the following exemplary embodiment are mere examples, and are not intended to limit the present disclosure. Therefore, among the structural elements in the following exemplary embodiment, structural elements not recited in any one of the independent claims are described as optional structural elements.

Note that the figures are schematic diagrams and are not necessarily precise illustrations. Therefore, for example, scale reduction and the like in the figures are not necessarily the same. Furthermore, in the figures, substantially identical elements are assigned the same reference signs, and overlapping description will be omitted or simplified.

In the present specification and the drawings, the X-axis, the Y-axis, and the Z-axis represent three axes of the right-handed three-dimensional Cartesian coordinate system. In the exemplary embodiment, the Z-axis direction is a direction of movement of the pusher, the Y-axis direction is a direction in which the conductor extends, and the X-axis direction is the width direction of the conductor. In the present specification, the phrase “as viewed from above” indicates viewing from the positive side of the Z-axis to the negative side of the Z-axis, the phrase “in a cross-sectional view” indicates viewing a cut surface of the breaker device that has been cut through by a plane extending through the Z-axis and parallel to the Z-axis, and the term “lateral” indicates a direction orthogonal to the Z-axis direction. In the present specification, the Z-axis direction is also referred to as an up-down direction. The up-down direction of the breaker device in the present specification merely indicates relative positioning of elements included in the breaker device for the sake of description of the exemplary embodiment. For example, in the present specification, the terms “up/upward/above/top” and “down/downward/below/bottom” do not indicate an upward direction (vertically upward) and a downward direction (vertically downward) in a sense of absolute space, but are used as terms defined by relative positioning on the basis of the direction of movement of the pusher. The posture of the breaker device when installed is not limited by the directions illustrated in the drawings.

Furthermore, in the present specification, terms indicating the relationship between elements such as being equal, terms indicating the shapes of elements such as a circular column and a square, numerical values, and numerical ranges are not expressions referring to only exact meanings, but are expressions referring to substantially equivalent ranges including, for example, approximately a few percent (or approximately 10%) differences.

Furthermore, in the present specification, ordinal numbers such as “first” and “second” do not indicate the number of structural elements or the sequence of structural elements, but are used for the purpose of avoiding confusion and distinguishing between structural elements of the same kind, unless otherwise noted.

Exemplary Embodiment

Hereinafter, the breaker device according to the present exemplary embodiment will be described with reference toFIG.1toFIG.4,FIG.6, andFIG.7.

[1. Configuration of Breaker Device]

First, the configuration of the breaker device according to the present exemplary embodiment will be described with reference toFIG.1toFIG.3,FIG.6, andFIG.7.FIG.1is a perspective view illustrating breaker device1according to the present exemplary embodiment.FIG.2AandFIG.6are cross-sectional views illustrating the configuration of breaker device1according to the present exemplary embodiment before an interrupting operation.FIG.2BandFIG.7are cross-sectional views illustrating the configuration of breaker device1according to the present exemplary embodiment after the interrupting operation.

FIG.1illustrates breaker device1that has rotated around the Z-axis as an axis of rotation from the state thereof in a front view, assuming that a view projected in the X-axis direction is a front view.FIG.2Ais a cross-sectional view of breaker device1during a non-interrupting operation (in the initial state) when taken along the XZ plane, andFIG.6is a cross-sectional view of breaker device1during a non-interrupting operation (in the initial state) when taken along the YZ plane. The position of pusher60illustrated inFIG.2AandFIG.6is one example of the first position (the initial position).FIG.2Bis a cross-sectional view of breaker device1after the interrupting operation when taken along the XZ plane, andFIG.7is a cross-sectional view of breaker device1after the interrupting operation when taken along the YZ plane. The position of pusher60illustrated inFIG.2BandFIG.7is one example of the second position.

As illustrated inFIG.1toFIG.2B, breaker device1includes igniter10, upper casing20, lower casing30, resin member40, conductor50, pusher60, protective portion80, and elastic members90,92,94,96. Breaker device1is a device that is mounted on an object including an electrical circuit and operates to interrupt the electrical circuit when an anomaly occurs in the electrical circuit, a system, or the like in the object, to thereby prevent damage caused by the anomaly from becoming severe. For example, breaker device1is mounted on a vehicle, which is one example of the object, and is connected between a motor and a battery (for example, a lithium-ion battery) for driving the motor to interrupt the electrical connection between the motor and the battery for driving the motor at the time of emergency such as an abnormal time or the time of an accident. Note that the object may be other than a vehicle; examples of the object include, but are not limited to, a home appliance and a photovoltaic system.

Igniter10, which holds gunpowder therein, includes lid portion11provided between the gunpowder and pusher60, is disposed in recess61, and generates gas. For example, igniter10is an electric igniter including: a gunpower portion including an ignition charge; and a conducting pin for passing an electric current through the gunpowder portion. During operation, an operating current for igniting the ignition charge is supplied from an external power supply to the conducting pin, thus the ignition charge is ignited and burnt, and gas (combustion gas) is generated. Note that when recess61is formed, breaker device1can be reduced in size.

Igniter10is fixed to small-diameter portion21located at the top of upper casing20.

Upper casing20and lower casing30, which are members constituting the outer full of breaker device1, house igniter10, a portion of each of resin member40and conductor50, pusher60, protective portion80, and elastic members92,94,96. Space70extending in the up-down direction is formed inside upper casing20and lower casing30. Space70is a space formed in the shape of a circular cylinder so that pusher60can move therein. Pusher60is housed in an area of space70that is located at the upper end (on the positive side of the Z-axis) in the up-down direction (the Z-axis direction).

Each of upper casing20and lower casing30is formed of a metal such as stainless steel (SUS), but may be formed of other metals such as aluminum. The outer shape of each of upper casing20and lower casing30is, but not limited to, a circular column. Upper casing20and lower casing30are connected and fixed by welding or the like, for example. Each of upper casing20and lower casing30is one example of the casing (the cover member).

Upper casing20, which is one example of the first casing and is a cylinder member having the shape of a circular cylinder with a step, for example, is hollow inside. Upper casing20includes: small-diameter portion21located in an upper area; large-diameter portion23located in a lower area; connecting portion22that connects these small-diameter and large-diameter portions; and upper fixing portion24. Small-diameter portion21, connecting portion22, large-diameter portion23, and upper fixing portion24are integrally formed. Small-diameter portion21and large-diameter portion23are coaxially disposed, and large-diameter portion23is larger in diameter than small-diameter portion21. Small-diameter portion21, connecting portion22, and large-diameter portion23form first body portion20awhich houses igniter10and pusher60located at the first position.

Upper fixing portion24, which is a part for fixing upper casing20and lower casing30, is provided so as to protrude downward from first body portion20a(for example, large-diameter portion23).

Lower casing30, which is one example of the second casing and is a member having the shape of a hollow cylinder with a closed bottom, includes protruding portion30athat protrudes upward. Specifically, lower casing30includes protruding portion30a, bottom portion33, side wall portion34, and lower fixing portion35. Protruding portion30a, bottom portion33, side wall portion34, and lower fixing portion35are integrally formed. Protruding portion30a, bottom portion33, and side wall portion34form second body portion30bwhich houses pusher60that has moved to the second position and separating portion51that has been cut off by pusher60that has moved to the second position. Second body portion30bis located below first body portion20a.

Note that in the present specification, being integrally formed indicates at least one of the following: that components are formed of the same material; that components are formed at the same time; and that components are the same object (a single object), for example.

Protruding portion30ais located below separating portion51and configured to protrude upward in space70. Protruding portion30ais connected to one end of bottom portion33and protrudes upward (on the positive side of the Z-axis) from bottom portion33in space70. Protruding portion30ais configured to contact pusher60that has moved downward by the gas generated by igniter10and then deform downward by being pressed by pusher60. This means that protruding portion30ahas the function of absorbing impact (stress) from pusher60by deformation.

Protruding portion30aforming the recess of lower casing30is exposed as viewed from the outside of breaker device1when breaker device1is viewed from the negative side of the Z-axis to the positive side of the Z-axis. In the present exemplary embodiment, protruding portion30ais tapered upward in space70, but the shape of protruding portion30ais not limited to this tapered shape.

Note that in the present specification, coming into contact means the state where stress can be transmitted from one of two members to the other and may represent direct contact between two members or may represent arrangement of two members with another member interposed therebetween such that stress can be transmitted from one of the two members to the other via the other member. For example, contact herein may represent direct contact between protruding portion30aand separating portion51or may represent arrangement of protruding portion30aand separating portion51such that stress on protruding portion30acan be transmitted to separating portion51via another member disposed between protruding portion30aand separating portion51. In the latter example, for example, arc-extinguishing material may be disposed between protruding portion30aand separating portion51or separating portion51may be disposed between protruding portion30aand pusher60.

Bottom portion33connects protruding portion30aand side wall portion34. In other words, protruding portion30aand side wall portion34aare connected via bottom portion33. Bottom portion33has an outer surface and an inner surface each inclining upward from protruding portion30ato side wall portion34.

Side wall portion34is connected to the other end of bottom portion33and is formed so as to extend upward from bottom portion33. Side wall portion34has the shape of a cylinder; in the present exemplary embodiment, side wall portion34has the shape of a circular cylinder. Side wall portion34is disposed coaxially with small-diameter portion21and large-diameter portion23. The diameter of side wall portion34is equal to the diameter of large-diameter portion23, for example.

Lower fixing portion35, which is a part for fixing upper casing20and lower casing30, is provided so as to protrude upward from second body portion30b(for example, side wall portion34). Lower fixing portion35is provided at a position corresponding to upper fixing portion24, and is disposed so as to at least partially overlap upper fixing portion24as viewed in the radial direction (in the X-axis direction in the cross-sections illustrated inFIG.2AandFIG.2B). For example, upper fixing portion24and lower fixing portion35overlap each other as viewed in the radial direction and are fixed in contact with each other.

In the present embodiment, lower fixing portion35is connected (joined) to upper fixing portion24; for example, lower fixing portion35is connected to upper fixing portion24by welding. Lower fixing portion35is joined to upper fixing portion24by welding portion110. Welding portion110is a portion at which lower fixing portion35and upper fixing portion24are welded. The welding is laser beam welding, but an arbitrary method such as tungsten inert gas (TIG) welding or projection welding may be used.

Note that lower fixing portion35may be connected to upper fixing portion24using a method other than welding; for example, solder may be used for the connection.

Protruding portion30a, bottom portion33, side wall portion34, and lower fixing portion35have the same thickness in the present exemplary embodiment, but may have different thicknesses, for example.

Next, upper casing20and lower casing30will be described with further reference toFIG.3.FIG.3is an exploded perspective view illustrating upper casing20and lower casing30according to the present exemplary embodiment. Note thatFIG.3illustrates only upper casing20and lower casing30among the structural elements of breaker device1.

As illustrated inFIG.2AtoFIG.3,FIG.5, andFIG.6, upper fixing portion24includes first fixing portion24aand third fixing portion24b, and lower fixing portion35includes second fixing portion35aand fourth fixing portion35b.

First fixing portion24aand third fixing portion24b, each of which is in the shape of an arc as viewed from above, are provided at opposite positions so as to protrude downward from first body portion20a. Furthermore, as illustrated inFIG.3, recess25is provided between first fixing portion24aand third fixing portion24bin the circumferential direction. Separating portion51is disposed in the space surrounded by recesses25,36in the state where lower fixing portion35is fixed to upper fixing portion24. Thus, first fixing portion24aand third fixing portion24bare disposed at opposite ends of separating portion51in the width direction (in the X-axis direction).

As illustrated inFIG.2AtoFIG.3,FIG.5, andFIG.6, second fixing portion35aand fourth fixing portion35b, each of which is in the shape of an arc as viewed from above, are provided at opposite positions so as to protrude upward from second body portion30b. Furthermore, as illustrated inFIG.3, recess36is provided between second fixing portion35aand fourth fixing portion35bin the circumferential direction. Thus, second fixing portion35aand fourth fixing portion35bare disposed at opposite ends of separating portion51in the width direction (in the X-axis direction).

In the state where lower fixing portion35is fixed to upper fixing portion24, first fixing portion24aand second fixing portion35aoverlap at least partially in the radial direction, and third fixing portion24band fourth fixing portion35boverlap at least partially in the radial direction. As a result, second fixing portion35acan be joined to first fixing portion24aby welding, and fourth fixing portion35bcan be joined to third fixing portion24bby welding. Thus, in the present embodiment, welding portions110are provided at opposite ends of separating portion51in the width direction (in the X-axis direction).

Furthermore, at least one of recesses25,36functions as a guide for positioning separating portion51when assembling breaker device1. This means that when at least one of recesses25,36is provided, assembly of breaker device1is made easier.

Note that in the present exemplary embodiment, as illustrated inFIG.2AtoFIG.3,FIG.5, andFIG.6, first fixing portion24ais disposed outward of second fixing portion35aand third fixing portion24bis disposed outward of fourth fixing portion35bin the state where lower fixing portion35is fixed to upper fixing portion24; however, the positional relationship between these fixing portions is not limited to this example.

For example, as illustrated inFIG.5, second fixing portion35a(lower fixing portion35) may be disposed outward of first fixing portion24a(upper fixing portion24), and fourth fixing portion35b(lower fixing portion35) may be disposed outward of third fixing portion24b(upper fixing portion24). Furthermore, one of second fixing portion35aand fourth fixing portion35bmay be disposed outward of upper fixing portion24.

Note that radially overlapping parts of first fixing portion24aand second fixing portion35aother than welding portion110may or may not be in contact. Similarly, radially overlapping parts of third fixing portion24band fourth fixing portion35bother than welding portion110may or may not be in contact.

Welding portion110preferably has a large area from the perspective of effectively distributing stress imposed on protruding portion30a, etc. For example, welding portion110may be provided in the shape of an arc. In other words, upper fixing portion24and lower fixing portion35may be surface-welded. With this, stress imposed on lower casing30can be effectively distributed to upper casing20; thus, deformation of breaker device1can be minimized. Furthermore, the strength of breaker device1can be improved.

Next, one example of a welding method will be specifically described. Here, the laser beam welding, which is one welding method, will be described. Note that as described above, the laser beam welding is one example of the method in which upper fixing portion24and lower fixing portion35are welded together; these portions may be welded in another method.

As indicated by the arrows inFIG.9AandFIG.9B, a laser beam is emitted to welding portion110in a direction in which upper fixing portion24and lower fixing portion35overlap each other (in the X-axis direction), and thus upper fixing portion24and lower fixing portion35are welded together.

Note that as illustrated inFIG.9A, in the case where upper fixing portion24is located outward of lower fixing portion35, the thickness of upper fixing portion24is preferably less than the thickness of lower fixing portion35. With this configuration, the welding is likely to be deeply achieved, and the area of welding between upper fixing portion24and lower fixing portion35can be easily increased.

In contrast, as illustrated inFIG.9B, in the case where upper fixing portion24is located inward of lower fixing portion35, the thickness of lower fixing portion35is preferably less than the thickness of upper fixing portion24. With this configuration, the welding is likely to be deeply achieved, and the area of welding between upper fixing portion24and lower fixing portion35can be easily increased.

The following will describe another welding method with which the area of welding can be easily increased.

For example, there is a welding method in which a laser beam is emitted to the lower end of upper fixing portion24diagonally upward from below (in the direction indicated by the arrow inFIG.8A). Compared to the welding method in which a laser beam is emitted along the X-axis to the portion at which upper fixing portion24and lower fixing portion35overlap each other as described with reference toFIG.9A, it is possible to further increase the area of welding portion110with ease at which upper fixing portion24and the lower fixing portion are welded together, with the method in which a laser beam is emitted to the lower end of upper fixing portion24diagonally upward from below.

In contrast, as illustrated inFIG.8B, in the case where upper fixing portion24is located inward of lower fixing portion35, there is a welding method in which a laser beam is emitted to the upper end of lower fixing portion35diagonally downward from above (as indicated by the arrow inFIG.8B). Compared to the welding method in which a laser beam is emitted along the X-axis to the portion at which upper fixing portion24and lower fixing portion35overlap each other as described with reference toFIG.9B, it is possible to further increase the area of welding portion110with ease at which upper fixing portion24and the lower fixing portion are welded together, with the method in which a laser beam is emitted to the upper end of lower fixing portion35diagonally downward from above. With reference back toFIG.1toFIG.2B,FIG.6, andFIG.7, details of the configuration of breaker device1will be described.

Resin member40is a member that covers a portion of conductor50. Furthermore, resin member40is a part of structural elements that form space70. Resin member40includes embedding portion41, first cylindrical portion42, and second cylindrical portion43.

Embedding portion41is a part of resin member40in which conductor50is embedded. Embedding portion41is partially exposed from the casing, for example. Embedding portion41has a through-hole in which conductor50(specifically, holding portion52) is disposed.

First cylindrical portion42, which is a part of resin member40that is disposed in the casing, is where pusher60is disposed during a non-interrupting operation (while no gas is generated by igniter10). In other words, first cylindrical portion42is located between the casing and pusher60. The inner diameter of first cylindrical portion42is less than the inner diameter of second cylindrical portion43.

Second cylindrical portion43, which is a part of resin member40that is disposed in the casing, is a part located below first cylindrical portion42. The inner diameter of second cylindrical portion43is greater than the inner diameter of first cylindrical portion42. Thus, the volume of the lower area of space70can be made large. This makes it possible to reduce an increase in the pressure inside the casing that is caused by the gas generated by igniter10and the following movement of pusher60, meaning that the deformation of breaker device1can be minimized.

In this manner, pusher60moves in space70formed by first cylindrical portion42and second cylindrical portion43. Note that first cylindrical portion42and second cylindrical portion43are not limited to having different inner diameters and may have the same inner diameter.

Furthermore, resin member40includes inner side wall40a, first outer side wall40b, and second outer side wall40c. First outer side wall40band second outer side wall40care walls of the recesses formed in the circumferential direction on the outer side wall of resin member40.

Inner side wall40a, which is the inner surface of resin member40, faces outer side wall60aof pusher60.

First outer side wall40bis a part disposed in the casing, at a level above separating portion51, and covered by upper casing20. First outer side wall40bis circumferentially provided so as to face large-diameter portion23in a cross-sectional view.

Second outer side wall40cis a part disposed in the casing, at a level below separating portion51, and covered by lower casing30. Second outer side wall40cis circumferentially provided so as to face side wall portion34in a cross-sectional view.

Conductor50is an electrically conductive metal body that is partially located in upper casing20and lower casing30. When breaker device1is mounted on a predetermined electrical circuit, conductor50forms a part of said electrical circuit and is also referred to as a busbar. Conductor50is a flat member held on resin member40and disposed so as to cross the interior of each of upper casing20and lower casing30. Conductor50includes separating portion51and holding portion52.

Conductor50can be formed of a metal such as copper (Cu), for example. Note that conductor50may be formed of a metal other than copper or may be formed of an alloy of copper and another metal. For example, conductor50may contain manganese (Mn), nickel (Ni), platinum (Pt), or the like.

Separating portion51, which is a part of conductor50that is cut off by pusher60under the pressure of the gas generated by igniter10, is located below pusher60at the initial position.

Holding portion52is a part of conductor50that is held by resin member40. Holding portion52is a part that does not overlap pusher60as viewed from above; for example, holding portion52is a part that overlaps resin member40as viewed from above and is a part located outside of the casing. Holding portion52remains held by resin member40even after separating portion51is cut off.

Pusher60is positioned below igniter10and disposed so as to be able to move downward and, for example, when an anomaly occurs in the system, moves downward to cut conductor50and interrupt the flow of an electric current through the electrical circuit as an emergency measure. Thus, pusher60is configured to cut off separating portion51from conductor50under the pressure of the gas generated by igniter10. As described, pusher60is disposed at a first position between separating portion51and igniter10(refer toFIG.2A) and moves from the first position to a second position located below the first position by cutting off separating portion51on the way. The second position is, for example, the position of pusher60when separating portion51comes into contact with protruding portion30aafter pusher60moves downward together with separating portion51.

Pusher60is formed from an insulating member such as a synthetic resin, for example. In the present exemplary embodiment, pusher60is formed from nylon. Pusher60has the shape of a circular column with an outer diameter corresponding to the inner diameter of small-diameter portion21of upper casing20. Furthermore, pusher60includes recess61, and igniter10is disposed inside recess61. Note that the shape of pusher60is not limited to said shape and can be changed, as appropriate, according to the shape, etc., of each of upper casing20and lower casing30. Recess61is an upper portion of pusher60where a recess directed downward is provided.

In the example illustrated inFIG.2A, recess61is a portion with a lateral surface surrounded by small-diameter portion21and connecting portion22in the state where breaker device1has not performed the interrupting operation.

Recess61includes: first portion62having a diameter (for example, an inner diameter) greater than the diameter of first cylindrical portion81of protective portion80; and second portion63located below first portion62and having a diameter (for example, an inner diameter) greater than the diameter of second cylindrical portion82, as viewed from above. The diameter of first portion62is greater than the diameter of second portion63as viewed from above. For example, in a cross-sectional view, the inner wall of first portion62is tapered with a diameter reduced toward second portion63, but may be, for example, in the shape of a staircase with a diameter reduced stepwise.

Protective portion80is a structural element for protecting pusher60from being damaged by lid portion11of igniter10when igniter10generates gas. Specifically, protective portion80is a member serving as a barrier to a part of lid portion11that may open wide, to reduce the occurrence of said part opened as a result of the gas generation by igniter10coming into contact with pusher60and damaging recess61of pusher60.

Protective portion80is provided on the casing (for example, upper casing20) or igniter10and includes a part located inside recess61. In the present exemplary embodiment, protective portion80is provided on the casing (specifically, small-diameter portion21). Protective portion80is fixed to small-diameter portion21by welding, for example, but the fixing method is not limited to welding.

First cylindrical portion81, which is a part in the shape of a cylinder surrounding the lateral side of igniter10, has a shape corresponding to igniter10. In the present exemplary embodiment, first cylindrical portion81is formed in the shape of a staircase (for example, in the form of a two-step staircase), the diameter (for example, the inner diameter) of which is reduced stepwise downward in a cross-sectional view. Note that the shape of first cylindrical portion81is not limited to this shape; for example, first cylindrical portion81may be tapered with a diameter reduced downward or may have another shape.

First cylindrical portion81may be at least partially in contact with igniter10. Second cylindrical portion82is disposed at the lower end of first cylindrical portion81.

First cylindrical portion81includes flange portion83at the top. Flange portion83, which is a ring-shaped part (for example, a plate-shaped member) formed so as to protrude outward from the upper end of first cylindrical portion81as viewed from above, is fixed to small-diameter portion21by welding or the like. At least a part of flange portion83is disposed between first portion62and small-diameter portion21, for example. Thus, first cylindrical portion81includes a part connected to the casing and is fixed to the casing.

Second cylindrical portion82is a ring-shaped part located below first cylindrical portion81and having a diameter (for example, an inner diameter) less than the diameter of first cylindrical portion81. Second cylindrical portion82is a part that protrudes straight from the lower end of first cylindrical portion81on the negative side of the Z-axis and when the gas is generated, comes into contact with lid portion11. The lower end (the end located on the negative side of the Z-axis, that is, the lowest end, for example) of second cylindrical portion82is located at a level below (on the negative side of the Z-axis from) the lower end (the end located on the negative side of the Z-axis, that is, the lowest end, for example) of lid portion11in the state where no gas is generated.

Protective portion80is formed of a metal such as stainless steel (SUS), for example, but may be formed of other metals such as aluminum or may be formed of a resin (for example, a resin different from that of pusher60).

As illustrated inFIG.2A,FIG.2B,FIG.6, andFIG.7, resin members90,92,94,96, which are elastic members such as rubber, are O-rings each formed in the shape of a ring. Each of elastic members90,92,94,96is disposed in the state of being pressed (a deformed state).

Elastic member90is disposed in the space formed between small-diameter portion21, igniter10, and fixing member100for fixing igniter10disposed in recess61. Elastic member90is in contact with each of fixing member100, igniter10, and small-diameter portion21and, for example, is pressed by each of fixing member100, igniter10, and small-diameter portion21.

Elastic member92is disposed to be positioned between the casing and pusher60in such a manner as to be pressed against the casing and press the outer side surface (for example, outer side wall60a) of pusher60. Elastic member92is disposed so as to extend along the outer side surface of pusher60. In the present exemplary embodiment, elastic member92is disposed in the space formed between the casing (for example, connecting portion22), pusher60, and resin member40in order to keep the internal space of recess61and the space exterior to said internal space (for example, the space between pusher60and resin member40) from being spatially connected. Elastic member92reduces the leakage of the gas generated by igniter10from the internal space of recess61to the exterior space. With this, it is possible to minimize a reduction in the pressure of the gas inside recess61that is due to the gas generated by igniter10escaping from the internal space of recess61.

In the present exemplary embodiment, elastic member92is in contact (for example, surface contact) with the casing, pusher60, and resin member40and, for example, is pressed by each of the casing, pusher60, and resin member40.

The shape of a cross section of elastic member92when pressed is triangular, but is not limited to this shape. The shape of the cross section of elastic member92when not pressed is not limited as long as the internal space of recess61and conductor50can be spatially separated after pressing; said shape may be a circle, may be a polygon (for example, a square), or may be an ellipse.

Note that in the present specification, the meaning of the term “pressing” includes, in addition to a situation where one member presses the other member, a situation where with a repulsive force generated as a result of elastic deformation of said other member, said other member presses said one member or another member.

Elastic member94, which is one example of the first elastic member, is disposed in the space formed above conductor50, between the casing (for example, large-diameter portion23) and a circumferential recess formed on resin member40, in order to keep the exterior space and the space located above conductor50from being spatially connected. In the present exemplary embodiment, elastic member94is in contact with each of first outer side wall40bof resin member40and large-diameter portion23and, for example, is pressed by each of first outer side wall40bof resin member40and large-diameter portion23.

When the internal pressure in the casing increases due to, for example, gas generated by igniter10or an electric arc generated when pusher60cuts off separating portion51, resin member40is pressed to the outside of breaker device1, and upper casing20is pressed upward and squeezes resin member40because of the structure in which the overlapping portions of upper casing20and lower casing30are fixed. Therefore, with resin member40and upper casing20, elastic member94is further pressed compared to the initial state. This makes it possible to reduce leakage of high-temperature gas to the outside of breaker device1through the spacing between upper casing20and resin member40.

Elastic member96, which is one example of the second elastic member, is disposed in the space formed below conductor50, between lower casing30(for example, side wall portion34) and a circumferential recess formed on resin member40, in order to keep the exterior space and the space located below conductor50from being spatially connected. In the present exemplary embodiment, elastic member96is in contact with each of second outer side wall40cof resin member40and side wall portion34and, for example, is pressed by each of second outer side wall40cof resin member40and side wall portion34.

When the internal pressure in the casing increases due to, for example, gas generated by igniter10or an electric arc generated when pusher60cuts off separating portion51, resin member40is pressed to the outside of breaker device1, and lower casing30is pressed downward and squeezes resin member40because of the structure in which the overlapping portions of upper casing20and lower casing30are fixed. Therefore, with resin member40and lower casing30, elastic member96is further pressed compared to the initial state. This makes it possible to reduce leakage of high-temperature gas to the outside of breaker device1through the spacing between lower casing30and resin member40.

Note that elastic members94,96are not limited to being disposed in the circumferential recesses without spacing; spacing may be formed in at least one of the up and down directions.

[2. Method for Manufacturing Breaker Device]

Next, the method for manufacturing breaker device1configured as described above will be described with reference toFIG.4.FIG.4is a flowchart illustrating a manufacturing process of breaker device1according to the present exemplary embodiment.

As illustrated inFIG.4, upper casing20is produced by molding or the like (S10), and lower casing30is produced by molding or the like (S20). Note that Step S20may be performed first so that Step S10is performed after Step S20or Step S10and Step S20may be performed in parallel.

In Step S10, protective portion80is further provided on upper casing20. For example, protective portion80is fixed to upper casing20by welding or the like. Furthermore, in Step S20, protruding portion30ais formed at the same time as lower casing30is produced by molding.

Next, upper casing20and lower casing30are fixed (S30). For example, upper casing20and lower casing30are fixed by welding or the like in the state where igniter10, resin member40, conductor50, pusher60, protective portion80, and elastic members90,92,94,96are housed in these casings. For example, first fixing portion24aand second fixing portion35aare joined together by welding, and third fixing portion24band fourth fixing portion35bare joined together by welding; thus, lower casing30is fixed to upper casing20. As a result, breaker device1described above is produced.

It is sufficient that in Step S30, at least one of the set of first fixing portion24aand second fixing portion35aand the set of third fixing portion24band fourth fixing portion35bbe fixed by welding or the like. While the welding is performed in the circumferential direction at the radially overlapping parts of first fixing portion24aand second fixing portion35a, the welding may be performed in the entire circumferential area at the radially overlapping parts or may be performed only a portion of the circumferential area at the radially overlapping parts.

(Configuration of Another Breaker Device)

Next, breaker device1A in which separating portion51has a different structure will be described with reference toFIG.10andFIG.11.FIG.10is a cross-sectional view illustrating the configuration of breaker device1A according to another exemplary embodiment before an interrupting operation.FIG.11is a cross-sectional view illustrating the configuration of breaker device1A according to another exemplary embodiment illustrated inFIG.10after the interrupting operation. Note that inFIG.10andFIG.11, elements that are substantially the same as those in breaker device1described above will be assigned the same reference signs as those in breaker device1, and description of the elements will be omitted.

In breaker device1described above, pusher60cuts off separating portion51from conductor50under the pressure of the gas generated by igniter10, and thus separating portion51moves downward. In other words, when separating portion51is cut off from holding portion52, the electrical connection between separating portion51and holding portion52is cut off and as a result, conductor50becomes non-conducting. However, the breaker device according to the present disclosure does not necessarily need to be configured to cut off separating portion51.

For example, as illustrated inFIG.10andFIG.11, pusher60may move the separating portion downward under the pressure of the gas generated by igniter10and thereby place conductor50in a non-conducting state. In other words, separating portion51in contact with holding portion52may be moved downward so that separating portion51is separated from holding portion52, to place conductor50in a non-conducting state.

Other Exemplary Embodiments

The breaker devices according to one or more aspects have been described thus far on the basis of the exemplary embodiment, but the present disclosure is not limited to the exemplary embodiment. Various modifications to the present exemplary embodiment and forms configured by combining structural elements in different exemplary embodiments that can be conceived by those skilled in the art may be included within the present disclosure as long as these do not depart from the essence of the present disclosure.

For example, the above exemplary embodiment has described an example in which the first fixing portion and the second fixing portion protrude in the Z-axis direction, but this is not limiting; the first fixing portion and the second fixing portion may protrude at an acute angle relative to the Z-axis direction.

The order of the steps in the method for manufacturing the breaker device described in the above exemplary embodiment may be changed. Furthermore, the steps in the method for manufacturing the breaker device described in the above exemplary embodiment may be performed in a single step or may be performed in separate steps. Note that the phrase “the steps are performed in a single step” is intended to include a situation in which the steps are performed using a single device, a situation in which the steps are sequentially performed, and a situation in which the steps are performed at the same location. The term “separate steps” is intended to include a situation in which the steps are performed using separate devices, a situation in which the steps are performed at different times (for example, on different days), and a situation in which the steps are performed at different locations.

INDUSTRIAL APPLICABILITY

The present disclosure is useful in breaker devices that are disposed in an electrical circuit or the like.

REFERENCE SIGNS LIST