Cutoff device

Abstract

To provide a cutoff device that can improve the insulation performance.SOLUTION: A cutoff device 1 includes an igniter 10 that generates gas, a pusher 60 located below the igniter 10, a conductor 50 having a separation portion 51 located below the pusher 60 and a holding portion 52 connected to the separation portion 51, a lower housing 30 that is located below the separation portion 51 and is made of metal, an insulating member 110 that is located inside the lower housing 30 and below the separation portion 51, and a resin member 40 whose at least a portion is located inside the lower housing 30 and holds the holding portion 52, and the pusher 60 is configured to separate the separation portion 51 from the conductor 50 under pressure of the gas generated by the igniter 10, and the resin member 40 and the insulating member 110 cover the inner surface of the lower housing 30, an end 113 of the insulating member 110 overlaps with an end 43a of the resin member 40, and a lower end 43b of the end 43a of the resin member 40 is located below an upper end 113a of the end 113 of the insulating member 110.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present disclosure relates to an isolating device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is known a circuit breaker that is used by being connected to an electric circuit. Patent Document 1 discloses a circuit breaker in which a reinforcing frame is disposed inside a housing (casing) of the circuit breaker. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 003594 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in the electrical circuits of electric vehicles and the like, the importance of a circuit-breaker that can more reliably break an electrical circuit is increasing from the viewpoint of preventing serious damage.

[0005] Therefore, the present disclosure provides a circuit breaker capable of improving insulation performance. [Means for solving the problem]

[0006] A cutting device according to one aspect of the present disclosure comprises an igniter that generates gas, a conductor having an igniter, a pusher located below the igniter, a separation portion located below the pusher, and a retaining portion connected to the separation portion, a cover member located below the separation portion and made of metal, an insulating member located inside the cover member and below the separation portion, and a resin member at least a portion of which is located inside the cover member and holds the retaining portion, wherein the pusher is configured to separate the separation portion from the conductor under pressure of the gas generated by the igniter, the resin member and the insulating member cover an inner surface of the cover member, an end of the insulating member overlaps an end of the resin member, and a lower end of the end of the resin member is located below an upper end of the end of the insulating member. Effect of the Invention

[0007] According to one aspect of the present disclosure, a circuit breaker capable of improving insulation performance can be realized. [Brief description of the drawings]

[0008] [Figure 1A] FIG. 1A is a front view showing a blocking device according to a first embodiment. [Figure 1B] FIG. 1B is a perspective view showing the blocking device according to the first embodiment. [Figure 2A] FIG. 2A is a cross-sectional view showing the configuration of the circuit breaker according to the first embodiment before a circuit breaker operation. [Figure 2B] FIG. 2B is a cross-sectional view showing the configuration of the circuit breaker according to the first embodiment after a circuit breaker operation. [Figure 3A] FIG. 3A is a perspective view showing the insulating member according to the first embodiment as viewed from above. [Figure 3B] FIG. 3B is a front view showing the insulating member according to the first embodiment. [Figure 3C] FIG. 3C is a perspective view showing the insulating member according to the first embodiment as viewed from below. [Figure 4A]FIG. 4A is a perspective view showing the lower housing according to the first embodiment as viewed from above. FIG. [Figure 4B] FIG. 4B is a front view showing the lower housing according to the first embodiment. [Figure 4C] FIG. 4C is a perspective view showing the lower housing according to the first embodiment as viewed from below. [Diagram 5] FIG. 5 is a cross-sectional view showing a configuration of a circuit breaker according to the second embodiment before a circuit breaker operation. [Figure 6A] FIG. 6A is a perspective view showing an insulating member according to the second embodiment as viewed from above. [Figure 6B] FIG. 6B is a front view showing the insulating member according to the second embodiment. [Figure 6C] FIG. 6C is a perspective view showing the insulating member according to the second embodiment as viewed from below. [Figure 7] FIG. 7 is a cross-sectional view showing a configuration of a circuit breaker according to a modification of the second embodiment before a circuit breaker performs a circuit breaker operation. [Figure 8] FIG. 8 is a front view showing an insulating member according to a modified example of the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view showing a configuration of a circuit breaker according to the third embodiment before a circuit breaker operation. [Figure 10A] FIG. 10A is a perspective view showing an insulating member according to embodiment 3 as viewed from above. [Figure 10B] FIG. 10B is an exploded perspective view showing the insulating member according to the third embodiment as viewed from above. [Figure 11] FIG. 11 is a flowchart showing a manufacturing process of the interrupter according to the embodiment and the like. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A cutting device according to one aspect of the present disclosure comprises an igniter that generates gas, a conductor having an igniter, a pusher located below the igniter, a separation portion located below the pusher, and a retaining portion connected to the separation portion, a cover member located below the separation portion and made of metal, an insulating member located inside the cover member and below the separation portion, and a resin member at least a portion of which is located inside the cover member and holds the retaining portion, wherein the pusher is configured to separate the separation portion from the conductor under pressure of the gas generated by the igniter, the resin member and the insulating member cover an inner surface of the cover member, an end of the insulating member overlaps an end of the resin member, and a lower end of the end of the resin member is located below an upper end of the end of the insulating member.

[0010] As a result, the end of the insulating member and the end of the resin member are arranged to overlap, so that the arc or the conductive gas (hereinafter also referred to as conductive gas, etc.) generated by the arc is cooled when it flows between the end of the insulating member and the end of the resin member, and the conductivity of the conductive gas, etc. can be reduced. In other words, the conductive gas, etc. comes into contact with the metal cover member, and it is possible to prevent the current interrupted by the separation part being cut by the pusher from being re-conducted through the cover member. Therefore, from the viewpoint of preventing re-conduction, it is possible to improve the insulating performance of the circuit breaker.

[0011] Also, for example, the end of the insulating member may be located between the end of the resin member and the cover member.

[0012] As a result, the end of the insulating member is between the end of the resin member and the cover member, so that the creepage distance of the arc from the cut surface of the separation part to the cover member can be extended, and the arc can be easily extinguished. Also, the high-temperature conductive gas generated during the interruption operation causes the resin member to move (or deform) the insulating member in a direction toward the outside (radially outward) of the interrupter, so that the gap between the insulating member and the resin member can be made smaller, and the conductivity of the conductive gas, etc. can be effectively reduced. Therefore, the interrupter can be more reliably prevented from being re-conducted.

[0013] Also, for example, the end of the resin member may be located between the end of the insulating member and the cover member.

[0014] As a result, since the end of the resin member is located between the end of the insulating member and the cover member, the creeping distance of the arc from the cut surface of the separation part to the cover member can be extended, making it easier to extinguish the arc and more reliably preventing re-conduction.

[0015] Also, for example, the cover member may have a convex portion located below the insulating member, the convex portion protruding upward and being pressed by the pusher.

[0016] As a result, the convex portion of the cover member is positioned below the insulating member (i.e., the insulating member is positioned between the separation portion and the cover member), thereby extending the path along which the arc occurs and, as a result, re-continuity can be more reliably prevented.

[0017] Also, for example, a gap may be provided between the cover member and the insulating member, and the gap may be located below the insulating member.

[0018] As a result, the insulating member can move downward by the gap when pressed by the pusher, so that damage to the insulating member due to pressure from the pusher can be suppressed, and therefore, from the viewpoint of suppressing damage to the insulating member, the insulating performance of the circuit breaker can be improved.

[0019] Also, for example, a gap may be provided between the cover member and the insulating member, the insulating member may have a first portion covering the top of the convex portion of the cover member and a second portion located below the first portion, the second portion covering the inner surface of the bottom of the cover member, and the gap may be located between the bottom of the cover member and the lower surface of the second portion.

[0020] As a result, the insulating member can move downward by the gap when the protrusion is pressed by the pusher, so that damage to the insulating member due to pressure from the pusher can be suppressed, and therefore, from the viewpoint of suppressing damage to the insulating member, the insulating performance of the circuit breaker can be improved.

[0021] Also, for example, the insulating member may have a first member covering the top of the convex portion of the cover member and a second member arranged to overlap a portion of the first member, the second member covering the inner surface of the bottom of the cover member, and the first member and the second member may be separate bodies.

[0022] As a result, since the insulating member is composed of two members, the stress applied to the insulating member when the protrusion is pressed by the pusher can be dispersed, and therefore, damage to the insulating member can be suppressed. Therefore, from the viewpoint of suppressing damage to the insulating member, the insulating performance of the circuit breaker can be improved.

[0023] Also, for example, the resin member may have a buried portion in which the holding portion is buried, a first cylindrical portion in which the pusher is disposed, and a second cylindrical portion located lower than the first cylindrical portion and having a larger diameter than the first cylindrical portion, and the inner diameter of the second cylindrical portion may be smaller than the inner diameter of the insulating member.

[0024] As a result, the insulating member covers the inner surface of the cover member, so that it is possible to prevent re-conduction while maintaining the size of the space in which the arc extends (while preventing the circuit breaker from becoming too large).

[0025] Note that each of the embodiments described below is either a comprehensive or specific example. The numerical values, shapes, components, component arrangement and connection forms, steps, and order of steps shown in each of the embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components that are not described in an independent claim are described as optional components.

[0026] In addition, each figure is a schematic diagram and is not necessarily illustrated precisely. Therefore, for example, the scales in each figure do not necessarily match. In addition, in each figure, substantially the same configurations are given the same reference numerals, and duplicated explanations are omitted or simplified.

[0027] In addition, in this specification and drawings, the X-axis, Y-axis, and Z-axis indicate three axes of a right-handed three-dimensional Cartesian coordinate system. In each embodiment, the Z-axis direction is the moving direction of the pusher, the Y-axis direction is the extension direction of the conductor, and the X-axis direction is the width direction of the conductor. In addition, in this specification, "front view" means viewing from the X-axis positive side toward the X-axis negative side, "top view" means viewing from the Z-axis positive side toward the Z-axis negative side, "cross-sectional view" means viewing a cut surface of the cutter cut by a plane passing through the Z-axis and parallel to the Z-axis, and side means a direction perpendicular to the Z-axis direction. In this specification, the Z-axis direction is also described as the up-down direction. However, in this specification, the up-down direction of the cutter merely indicates the relative positional relationship of each element in the cutter for the convenience of explanation of each embodiment. For example, in this specification, the terms "upper" and "lower" do not refer to the upper direction (vertically upward) and lower direction (vertically downward) in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the moving direction of the pusher. Also, the orientation when installing the blocking device is not limited to the direction shown in the drawings.

[0028] Furthermore, in this specification, terms indicating the relationship between elements, such as equal and orthogonal, terms indicating the shape of an element, such as circle, as well as numerical values ​​and numerical ranges, are not expressions that only express a strict meaning, but are expressions that include a substantially equivalent range, for example, a difference of about a few percent (or about 10%).

[0029] In addition, in this specification, ordinal numbers such as "first" and "second" do not refer to the number or order of components, unless otherwise specified, but are used for the purpose of avoiding confusion and distinguishing between components of the same type.

[0030] (Embodiment 1) The configuration of the shutoff device according to the present embodiment will be described below with reference to Figs. 1A to 4C. Fig. 1A is a front view showing the shutoff device 1 according to the present embodiment. Fig. 1B is a perspective view showing the shutoff device 1 according to the present embodiment. Fig. 2A is a cross-sectional view showing the configuration of the shutoff device 1 according to the present embodiment before the shutoff operation. Fig. 2B is a cross-sectional view showing the configuration of the shutoff device 1 according to the present embodiment after the shutoff operation. Fig. 1B is a view in which the shutoff device 1 shown in Fig. 1A is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the shutoff device 1 as seen from below.

[0031] In the perspective view, when the three axes of the three-dimensional orthogonal coordinate system are drawn on the paper and some of them have the same direction, only one of the axes is shown. For example, in Fig. 1B, the X-axis and the Z-axis have the same direction on the paper, so only the Z-axis is shown.

[0032] As shown in FIG. 1A to FIG. 2B, the cutoff device 1 includes an igniter 10, an upper housing 20, a lower housing 30, a resin member 40, a conductor 50, a pusher 60, a protective part 80, elastic members 90, 92, 94, 96, and an insulating member 110. The cutoff device 1 is mounted on an object having an electric circuit, and is a device that operates when an abnormality occurs in an electric circuit, a system, or the like in the object, to cut off the electric circuit, thereby preventing damage from the abnormality from becoming greater. For example, the cutoff device 1 is mounted on a vehicle, which is an example of the object, and is connected between a motor and a battery (for example, a lithium-ion battery) for driving the motor, and cuts off the electrical connection between the motor and the battery for driving the motor in an emergency such as an abnormality or an accident. The object may be other than a vehicle, and examples thereof include, but are not limited to, home appliances and solar power generation systems.

[0033] The igniter 10 holds explosives therein, has a cover 11 provided between the explosives and a pusher 60, is placed in the recess 61, and generates gas. For example, the igniter 10 is an electric igniter having an explosive part having an ignition powder, and a conductive pin for conducting electricity with the explosive part. When activated, an operating current for igniting the ignition powder is supplied to the conductive pin from an external power source, thereby igniting and burning the ignition powder and generating gas (combustion gas). The formation of the recess 61 allows the circuit breaker 1 to be made more compact.

[0034] The igniter 10 is fixed to the upper small diameter portion 21 of the upper housing 20.

[0035] The upper housing 20 and the lower housing 30 are members that form the outer shell of the circuit breaker 1, and house the igniter 10, the resin member 40, a part of the conductor 50, the pusher 60, the protective part 80, the elastic members 92, 94, 96, and the insulating member 110. A space 70 extending in the vertical direction is formed inside the upper housing 20 and the lower housing 30. The space 70 is a cylindrical space that allows the pusher 60 to move. The pusher 60 is housed at the upper end side (Z-axis positive side) of the space 70 in the vertical direction (Z-axis direction).

[0036] The upper housing 20 and the lower housing 30 are each made of a metal such as stainless steel (SUS), but may be made of other metals such as aluminum. For example, the upper housing 20 and the lower housing 30 are made of a metal. Note that it is sufficient that at least the lower housing 30 is made of a metal, and the upper housing 20 may be made of, for example, a resin.

[0037] Furthermore, the upper housing 20 and the lower housing 30 have a cylindrical outer shape, but the shape is not limited thereto. Furthermore, the upper housing 20 and the lower housing 30 are directly connected and fixed, for example, by welding. The lower housing 30 is an example of a cover member. Furthermore, the upper housing 20 and the lower housing 30 are an example of a housing.

[0038] The upper housing 20 is, for example, a cylindrical member having a stepped cylindrical shape, and is hollow inside. The upper housing 20 has a small diameter portion 21 located at the top, a large diameter portion 23 located at the bottom, and a connection portion 22 that connects them. The small diameter portion 21, the connection portion 22, and the large diameter portion 23 are integrally formed. The small diameter portion 21 and the large diameter portion 23 are arranged coaxially, and the large diameter portion 23 has a larger diameter than the small diameter portion 21.

[0039] The lower housing 30 is located below the separation portion 51, is a hollow cylindrical member with a bottom, and has a protrusion 30a that protrudes upward. Specifically, the lower housing 30 has the protrusion 30a, a bottom 33, and a side wall 34. The protrusion 30a, the bottom 33, and the side wall 34 are integrally formed.

[0040] In this specification, integral formation means that each component part is formed from the same material, is formed simultaneously, and is the same (single) object.

[0041] The protruding portion 30a is located below the separating portion 51 and is configured to protrude upward in the space 70. The protruding portion 30a is connected to one end of the bottom portion 33 and protrudes upward (toward the positive side of the Z axis) from the bottom portion 33 in the space 70. The protruding portion 30a is configured to be pressed by the insulating member 110 that comes into contact with the pusher 60 that has moved downward due to the gas generated by the igniter 10 and deforms downward. In other words, the protruding portion 30a has a function of absorbing an impact (stress) from the pusher 60 by being pressed and deformed by the pusher 60. The protruding portion 30a is also located below the insulating member 110.

[0042] Furthermore, when the interrupter 1 is viewed from the negative side of the Z axis toward the positive side of the Z axis, the protruding portion 30a forming the recess of the lower housing 30 is exposed when viewed from the outside of the interrupter 1. In this embodiment, the protruding portion 30a has a shape that tapers upward in the space 70, but the shape is not limited thereto.

[0043] The bottom 33 connects the protrusion 30a and the side wall 34. In other words, the protrusion 30a and the side wall 34 are connected via the bottom 33. The outer surface and the inner surface of the bottom 33 are each inclined upward from the protrusion 30a toward the side wall 34.

[0044] The side wall portion 34 is connected to the other end of the bottom portion 33 and is formed to extend upward from the bottom portion 33. The side wall portion 34 has a tubular shape, and in this embodiment, has a cylindrical shape. The side wall portion 34 is disposed coaxially with the small diameter portion 21 and the large diameter portion 23. The side wall portion 34 has the same diameter as the large diameter portion 23, for example.

[0045] The thicknesses of the protrusion 30a, the bottom 33 and the side wall 34 are the same in this embodiment, but may be different from each other, for example.

[0046] At least a portion of the resin member 40 is located inside the lower housing 30, and covers a portion of the conductor 50 (specifically, the holding portion 52). It can also be said that the resin member 40 holds the holding portion 52. The resin member 40 is also a part of the components that form the space 70. The resin member 40 has an embedded portion 41, a first cylindrical portion 42, and a second cylindrical portion 43.

[0047] The embedded portion 41 is a portion of the resin member 40 in which the conductor 50 (specifically, the holding portion 52) is embedded. For example, a portion of the embedded portion 41 is exposed from the housing. A through hole is formed in the embedded portion 41 in which the conductor 50 (specifically, the holding portion 52) is disposed. The embedded portion 41 constitutes a portion of the first cylindrical portion 42.

[0048] The first cylindrical portion 42 is a portion of the resin member 40 that is disposed within the housing, and the pusher 60 is disposed inside the first cylindrical portion 42 when no cutoff operation is performed (when no gas is generated by the igniter 10). In other words, the first cylindrical portion 42 is located between the housing and the pusher 60. The first cylindrical portion 42 has a smaller inner diameter than the second cylindrical portion 43.

[0049] The second cylindrical portion 43 is a portion of the resin member 40 that is disposed in the housing, and is a portion that is located below the first cylindrical portion 42. The second cylindrical portion 43 has a larger diameter than the first cylindrical portion 42. For example, the inner diameter d2 (see FIG. 2A) of the second cylindrical portion 43 is larger than the inner diameter d1 (see FIG. 2A) of the first cylindrical portion 42. This allows the lower volume of the space 70 to be increased. Therefore, the increase in pressure in the housing due to the gas generated by the igniter 10 and the resulting movement of the pusher 60 downward can be suppressed, and deformation of the cutoff device 1 can be suppressed. The inner diameter d2 of the second cylindrical portion 43 is smaller than the inner diameter d3 of the insulating member 110. That is, the inner diameters increase in the order of the first cylindrical portion 42, the second cylindrical portion 43, the insulating member 110, and the lower housing 30.

[0050] The second cylindrical portion 43 has an end portion 43a on the lower side. The end portion 43a is disposed inside the lower housing 30, and is, for example, a portion below the elastic member 96. The end portion 43a is formed, for example, in a tapered shape in which the inner diameter increases toward the bottom, but the shape of the end portion 43a is not limited to being tapered.

[0051] In this manner, the pusher 60 moves within the space 70 formed by the first cylindrical portion 42 and the second cylindrical portion 43. Note that the first cylindrical portion 42 and the second cylindrical portion 43 are not limited to having different inner diameters, and may have the same inner diameter.

[0052] The conductor 50 is a conductive metal body, a portion of which is located inside the upper housing 20 and the lower housing 30. The conductor 50 forms part of a predetermined electric circuit when the circuit breaker 1 is attached to the electric circuit, and is also called a bus bar. The conductor 50 is a flat plate-like member that is held by the resin member 40 and disposed so as to traverse the insides of the upper housing 20 and the lower housing 30. The conductor 50 has a separation portion 51 and a holding portion 52.

[0053] The separation portion 51 is a portion of the conductor 50 that is separated by the pusher 60 when it receives the pressure of the gas generated by the igniter 10, and is located below the pusher 60 in the initial position.

[0054] The holding portion 52 is a portion of the conductor 50 that is connected to the separation portion 51 and is held by the resin member 40. The holding portion 52 is a portion that does not overlap with the pusher 60 in a top view, for example, a portion that overlaps with the resin member 40 in a top view and a portion that is located outside the housing. The holding portion 52 maintains a state in which it is held by the resin member 40 even after the separation portion 51 is separated.

[0055] The conductor 50 may be made of a metal such as copper (Cu). However, the conductor 50 may be made of a metal other than copper, or may be made of an alloy of copper and another metal. For example, the conductor 50 may be made of manganese (Mn), nickel (Ni), platinum (Pt), etc.

[0056] The pusher 60 is located below the igniter 10 and is arranged to be movable downward, and by moving downward when an abnormality occurs in the system, the pusher 60 cuts the conductor 50 and emergency cuts off the continuity in the electric circuit. In this way, the pusher 60 is configured to separate the separation part 51 from the conductor 50 by receiving the pressure of the gas generated by the igniter 10. In this way, the pusher 60 is arranged at a first position (see FIG. 2A) between the separation part 51 and the igniter 10, and moves from the first position toward a second position (see FIG. 2B) located below the first position by breaking the separation part 51. The second position is, for example, the position of the pusher 60 when the pusher 60 moves downward together with the separation part 51 and the separation part 51 comes into contact with the protrusion 30a.

[0057] The pusher 60 is formed of an insulating material such as synthetic resin. In this embodiment, the pusher 60 is formed of nylon. The pusher 60 has a cylindrical shape and has an outer diameter corresponding to the inner diameter of the small diameter portion 21 of the upper housing 20. The pusher 60 also has a recess 61, and the igniter 10 is disposed inside the recess 61. The shape of the pusher 60 is not limited to the above, and can be appropriately changed depending on the shapes of the upper housing 20 and the lower housing 30, etc. The recess 61 is the upper part of the pusher 60, and is a part where a recess facing downward is provided.

[0058] The recess 61 has, in a top view, a first portion 62 having a larger diameter (e.g., inner diameter) than the first cylindrical portion 81 of the protective portion 80, and a second portion 63 located below the first portion 62 and having a larger diameter (e.g., inner diameter) than the second cylindrical portion 82. In a top view, the diameter of the first portion 62 is larger than the diameter of the second portion 63. For example, in a cross-sectional view, the inner wall of the first portion 62 has a tapered shape in which the diameter decreases toward the second portion 63, but may also have a stepped shape in which the diameter decreases in stages.

[0059] The protective part 80 is a component for preventing the pusher 60 from being damaged by the opening 11a (see FIG. 2B) of the cover part 11 of the igniter 10 when the igniter 10 generates gas. Specifically, the protective part 80 is a member for preventing the opening 11a from opening too wide and preventing the opening 11a, which opens when the igniter 10 generates gas, from coming into contact with the pusher 60 and damaging the recess 61 of the pusher 60.

[0060] Protective portion 80 is provided on a housing (e.g., upper housing 20) or igniter 10, and has a portion located inside recess 61. In the present embodiment, protective portion 80 is provided on a housing (specifically, small diameter portion 21). Protective portion 80 is fixed to small diameter portion 21 by, for example, welding, but the fixing method is not limited thereto.

[0061] 2A and 2B, the protection portion 80 has a first cylindrical portion 81 and a second cylindrical portion 82. The first cylindrical portion 81 and the second cylindrical portion 82 are integrally formed.

[0062] The first cylindrical portion 81 is a cylindrical portion that surrounds the side of the igniter 10, and has a shape that conforms to the igniter 10. In the present embodiment, the first cylindrical portion 81 is formed in a stepped shape (e.g., a two-step stepped shape) in which the diameter (e.g., the inner diameter) decreases stepwise toward the bottom in a cross-sectional view. Note that the shape of the first cylindrical portion 81 is not limited to this, and for example, the first cylindrical portion 81 may be tapered in which the diameter decreases toward the bottom, or may have another shape.

[0063] The first cylindrical portion 81 may be in at least partial contact with the igniter 10. At the lower end of the first cylindrical portion 81, the second cylindrical portion 82 is disposed.

[0064] Moreover, the first cylindrical portion 81 has a flange portion 83 on the upper side. The flange portion 83 is an annular portion (e.g., a plate-shaped member) formed so as to protrude outward in a top view from the upper end of the first cylindrical portion 81, and is fixed to the small diameter portion 21 by welding or the like. For example, at least a portion of the flange portion 83 is disposed between the first part 62 and the small diameter portion 21. In this manner, the first cylindrical portion 81 has a portion connected to the housing and is fixed to the housing.

[0065] The second cylindrical portion 82 is located below the first cylindrical portion 81 and is an annular portion having a smaller diameter (e.g., inner diameter) than the first cylindrical portion 81. The second cylindrical portion 82 protrudes linearly from the lower end of the first cylindrical portion 81 toward the negative Z-axis side and is the portion that comes into contact with the lid portion 11 when gas is generated. The lower end (the end portion on the negative Z-axis side, e.g., the bottom end) of the second cylindrical portion 82 is located below (on the negative Z-axis side) than the lower end (the end portion on the negative Z-axis side, e.g., the bottom end) of the lid portion 11 in a state in which no gas is generated.

[0066] The protective portion 80 is formed of a metal such as stainless steel (SUS), 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 the pusher 60).

[0067] 2A and 2B, the elastic members 90, 92, 94, and 96 are elastic members such as rubber, and are O-rings formed in an annular shape. Each of the elastic members 90, 92, 94, and 96 is disposed in a pressed state (deformed state).

[0068] The elastic member 90 is disposed in a space formed between the fixing member 100 for fixing the igniter 10 disposed in the recess 61, the igniter 10, and the small diameter portion 21. The elastic member 90 is in contact with each of the fixing member 100, the igniter 10, and the small diameter portion 21, and is pressed by, for example, each of the fixing member 100, the igniter 10, and the small diameter portion 21.

[0069] The elastic member 92 is disposed between the housing and the pusher 60, and is pressed against the housing to press the outer surface of the pusher 60. The elastic member 92 is disposed along the outer surface of the pusher 60. In this embodiment, the elastic member 92 is disposed in a space formed between the housing (e.g., the connection portion 22), the pusher 60, and the resin member 40 in order to suppress spatial connection between the internal space of the recess 61 and a space outside the internal space (e.g., a space between the pusher 60 and the resin member 40). The elastic member 92 suppresses leakage of the gas generated by the igniter 10 from the internal space of the recess 61 to the external space. This suppresses the gas generated by the igniter 10 from escaping from the internal space of the recess 61, and the pressure of the gas in the recess 61 from decreasing.

[0070] In the present embodiment, the elastic member 92 is in contact (for example, surface contact) with the housing, the pusher 60, and the resin member 40, and is pressed by, for example, the housing, the pusher 60, and the resin member 40, respectively.

[0071] 2A, the elastic member 92 has a triangular cross-sectional shape when pressed, but is not limited thereto. The cross-sectional shape of the elastic member 92 when not pressed is not particularly limited as long as it can spatially separate the internal space of the recess 61 and the conductor 50 after pressing, and may be a circle, a polygon (e.g., a square), or an ellipse.

[0072] In this specification, "pressing" refers not only to one member pressing another member, but also to the pressing of the one member or another member by the repulsive force generated by the elastic deformation of the other member.

[0073] The elastic member 94 is disposed in a space formed above the conductor 50 and between a circumferential recess formed in the resin member 40 and a housing (e.g., large diameter portion 23) in order to prevent spatial connection between the space above the conductor 50 and the external space. In this embodiment, the elastic member 94 is in contact with both the resin member 40 and the large diameter portion 23 and is pressed by, for example, both the resin member 40 and the large diameter portion 23.

[0074] The elastic member 96 is disposed below the conductor 50 in a space formed between a circumferential recess formed in the resin member 40 and the lower housing 30 (e.g., the side wall portion 34) in order to prevent spatial connection between the space below the conductor 50 and the external space. In this embodiment, the elastic member 96 is in contact with both the resin member 40 and the side wall portion 34 and is pressed by, for example, both the resin member 40 and the side wall portion 34.

[0075] The elastic members 94 and 96 are not limited to being arranged without gaps in the circumferential recess, and may have gaps in at least one of the upper and lower directions.

[0076] The insulating member 110 is an insulating member located inside the lower housing 30 and below the separation portion 51. The insulating member 110 preferably has a shape that matches the shape of the lower housing 30. For example, if the lower housing 30 has an inclined portion (e.g., the bottom portion 33), the insulating member 110 preferably also has an inclined portion (e.g., a portion of the second portion 112 that is inclined). In this embodiment, the insulating member 110 is provided in a layer having a certain thickness along the inner surface of the lower housing 30. Furthermore, the thickness of the insulating member 110 may be thinner than the thickness of the lower housing 30, for example.

[0077] The insulating member 110 has a first portion 111 and a second portion 112 .

[0078] The first portion 111 is a portion of the insulating member 110 having a shape that conforms to the protrusion 30a, and covers the inner surface of the protrusion 30a. The first portion 111 is provided, for example, so as to cover the top of the protrusion 30a. In the present embodiment, the first portion 111 is provided so as to be in contact with the inner surface of the protrusion 30a.

[0079] The second portion 112 is located below the first portion 111 and covers the inner surface of the bottom portion 33. In the present embodiment, the second portion 112 is provided without contacting the bottom portion 33 before the interruption operation. As a result, a gap 72 (see FIG. 2A ) located below the insulating member 110 is provided between the insulating member 110 and the lower housing 30 (e.g., the bottom portion 33) (between the lower surface of the second portion 112 and the bottom portion 33). The gap 72 is an example of a gap.

[0080] Providing the gap 72 allows the insulating member 110 to move (deform) into the gap 72 when the protruding portion 30a is deformed, thereby making it possible to prevent the insulating member 110 from being damaged by stress. The second portion 112 also covers a part of the inner surface of the side wall portion 34. If the portion of the second portion 112 provided along the inner surface of the side wall portion 34 is defined as an end portion 113, in the example of Fig. 2A, the inner diameter d3 of the insulating member 110 is the distance in the Y-axis direction between the ends 113 that face each other in the radial direction.

[0081] The size of the gap 72 may be determined according to the expected deformation size of the convex portion 30a, for example by making the height (length in the Z-axis direction) of the convex portion 30a greater than the height of the convex shape of the insulating member 110.

[0082] The first portion 111 and the second portion 112 are integrally formed. The insulating member 110 is made of, for example, a resin having insulating properties (for example, a synthetic resin). For example, the insulating member 110 is formed by molding a resin.

[0083] The insulating member 110 may be realized by applying an insulating material to the inner surface of the lower housing 30. For example, the insulating member 110 may be formed by coating the inner surface of the lower housing 30 with an insulating material so as to cover the inner surface. In this case, the insulating member 110 and the lower housing 30 are provided integrally.

[0084] As shown in FIG. 2A and FIG. 2B, the resin member 40 and the insulating member 110 cover the inner surface of the lower housing 30 before and after the interruption operation. For example, the resin member 40 and the insulating member 110 may cover the inner surface of the lower housing 30 so that the inner surface of the lower housing 30 is not exposed. In addition, the resin member 40 and the insulating member 110 overlap each other in part when viewed in the radial direction. Specifically, the end 113 of the insulating member 110 and the end 43a of the resin member 40 overlap each other in the radial direction. More specifically, the lower end 43b of the end 43a of the resin member 40 is located below the upper end 113a of the end 113 of the insulating member 110. The lower end 43b is located below the upper end 113a along the circumferential direction. In addition, since the end 113 is provided outside the end 43a, the end 113 is located between the end 43a and the lower housing 30.

[0085] In addition, the end 113 and the end 43a may overlap, for example, by 1 mm or more in the Z-axis direction, more preferably by 3 mm or more, and even more preferably by 5 mm or more. 1 mm, 3 mm, and 5 mm are lengths in the Z-axis direction.

[0086] Further, a gap 74 is provided between the end 113 and the end 43a. The gap 74 may be provided over the entire circumferential direction, or may be provided over a portion of the circumferential direction. The gap 74 is a narrow gap through which a high-temperature conductive gas generated by an arc during an interruption operation can be cooled while passing through. The width of the gap 74 (the distance between the end 113 and the end 43a, which is the length in the Y-axis direction in the example of FIG. 2A) is 1 mm or less, for example, 0.5 mm or less. The width of the gap 74 is the average value of the distance between the end 113 and the end 43a in the circumferential direction, but may be a maximum value, a minimum value, a mode value, a median value, or the like.

[0087] As a result, when the high-temperature conductive gas flows into the gap 74, the conductive gas is cooled, and the conductivity of the conductive gas can be reduced. Since the conductivity of the conductive gas that has flowed out of the gap 74 has been reduced, even if the conductive gas comes into contact with the lower housing 30, the conductor 50 is prevented from becoming conductive again.

[0088] It is not necessary to provide the gap 74. In other words, the end 113 and the end 43a may be in contact with each other over the entire circumferential direction.

[0089] Here, the configurations of the insulating member 110 and the lower housing 30 will be further described with reference to Figs. 3A to 4C. Fig. 3A is a perspective view showing the insulating member 110 according to this embodiment as viewed from above. Fig. 3B is a front view showing the insulating member 110 according to this embodiment. Fig. 3C is a perspective view showing the insulating member 110 according to this embodiment as viewed from below. Fig. 3A is a view in which the insulating member 110 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the insulating member 110 shown in Fig. 3B as viewed from above, and Fig. 3C is a view in which the insulating member 110 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the insulating member 110 shown in Fig. 3B as viewed from below.

[0090] 3A to 3C, the first portion 111 of the insulating member 110 is a hollow, bottomless, truncated cone-shaped member. The second portion 112 has an end portion 113 and an inclined portion that connects the end portion 113 and the first portion 111. The inclined portion is tapered such that the inner diameter increases toward the end portion 113. The end portion 113 is a bottomless tubular member that extends in the Z-axis direction.

[0091] Fig. 4A is a perspective view showing the lower housing 30 according to the present embodiment as viewed from above. Fig. 4B is a front view showing the lower housing 30 according to the present embodiment. Fig. 4C is a perspective view showing the lower housing 30 according to the present embodiment as viewed from below. Fig. 4A is a view in which the lower housing 30 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the lower housing 30 shown in Fig. 4B as viewed from above, and Fig. 4C is a view in which the lower housing 30 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the lower housing 30 shown in Fig. 4B as viewed from below.

[0092] As shown in FIG. 4A to FIG. 4C, the convex portion 30a of the lower housing 30 is a hollow, bottomless truncated cone-shaped member. The bottom portion 33 is tapered such that the inner diameter increases toward the side wall portion 34. The side wall portion 34 is a bottomless tubular member extending in the Z-axis direction. The length of the side wall portion 34 in the Z-axis direction is longer than the length of the end portion 113 in the Z-axis direction. The inner diameter of the side wall portion 34 is larger than the inner diameter d3 of the end portion 113. The side wall portion 34 is configured to cover the end portion 113 from the outside. The fixing portion 35 is a portion for fixing the upper housing 20 and the lower housing 30, and is provided so as to protrude upward from the side wall portion 34. The fixing portion 35 is joined by welding or the like to a fixing portion (not shown) provided in the upper housing 20 so as to protrude downward.

[0093] As described above, the interrupter 1 has a configuration in which the inner surface of the lower housing 30 is not exposed, and the insulating resin members (the resin member 40 and the insulating member 110) partially overlap each other when viewed in the radial direction.

[0094] (Embodiment 2) Hereinafter, the configuration of the interrupting device according to the present embodiment will be described with reference to Figs. 5 to 6C. Fig. 5 is a cross-sectional view showing the configuration of the interrupting device 2 according to the present embodiment before the interrupting operation. Fig. 6A is a perspective view showing the insulating member 210 according to the present embodiment as viewed from above. Fig. 6B is a front view showing the insulating member 210 according to the present embodiment. Fig. 6C is a perspective view showing the insulating member 210 according to the present embodiment as viewed from below. Fig. 6A is a view in which the insulating member 210 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the insulating member 210 shown in Fig. 6B as viewed from above, and Fig. 6C is a view in which the insulating member 210 is rotated about the Y-axis direction as a rotation axis to obtain a perspective view of the insulating member 210 shown in Fig. 6B as viewed from below.

[0095] In the following, differences from embodiment 1 will be mainly described, and descriptions of contents that are the same as or similar to embodiment 1 will be omitted or simplified. The isolating device 2 according to this embodiment differs from the isolating device 1 according to embodiment 1 in that the lower housing 230 does not have a protrusion 30a and has a flat bottom surface.

[0096] As shown in FIG. 5, the circuit breaker 2 includes a lower housing 230 instead of the lower housing 30 of the circuit breaker 1, and an insulating member 210 instead of the insulating member 110.

[0097] The lower housing 230 has a plate-shaped portion 230a, a bottom portion 33, and a side wall portion 34. The plate-shaped portion 230a, the bottom portion 33, and the side wall portion 34 are integrally formed.

[0098] The plate-shaped portion 230a is a flat member, and in this embodiment, is disk-shaped. The inner surface of the plate-shaped portion 230a is flat.

[0099] 5 to 6C, insulating member 210 has a shape that fits the shape of lower housing 230. Insulating member 210 has first portion 211 and second portion 112. Insulating member 210 has first portion 211 and second portion 112. As shown in FIG.

[0100] The first portion 211 is provided opposite the plate-shaped portion 230a and covers the inner surface of the plate-shaped portion 230a. The first portion 211 is a flat plate-shaped member, and in this embodiment, is disk-shaped. In this embodiment, the first portion 211 is provided at a predetermined interval from the plate-shaped portion 230a without contacting the plate-shaped portion 230a before the interruption operation.

[0101] The second portion 212 is located above the first portion 211, and covers the inner surface of the bottom portion 33 and a part of the inner surface of the side wall portion 34. In the present embodiment, the second portion 112 is provided without contacting the bottom portion 33 before the interruption operation.

[0102] As a result, a gap 74 is provided between the insulating member 210 and the lower housing 230.

[0103] In the present embodiment, an example has been described in which the end 113 of the insulating member 210 is disposed between the end 43a of the resin member 40 and the lower housing 230 in the radial direction, but the end of the resin member may be disposed between the end of the insulating member and the lower housing. A breaking device having such a configuration will be described in the following modified example.

[0104] (Modification of the second embodiment) Hereinafter, the configuration of the interrupting device according to this modification will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a cross-sectional view showing the configuration of an interrupting device 2a according to this modification before an interrupting operation. Fig. 8 is a front view showing an insulating member 210a according to this modification.

[0105] 7, the interrupting device 2a includes an insulating member 210a instead of the insulating member 210 of the interrupting device 2, and a resin member 40 having an end 243a instead of the end 43a. As described above, the interrupting device 2a is configured such that the end 243a of the resin member 40 is located between the end 213a of the insulating member 210a and the lower housing 230.

[0106] The end portion 243a has an outer surface that contacts the lower housing 230 and an inner surface that is inclined.

[0107] 7 and 8, the insulating member 210a has a shape that fits the shapes of the lower housing 230 and the end portion 243a. The insulating member 210a has a first portion 211 and a second portion 212a.

[0108] The second portion 212a is located above the first portion 211, and covers the inner surface of the bottom portion 33 and the inner surface (inclined surface) of the end portion 243a. In the present embodiment, the second portion 212a is provided so as not to contact the bottom portion 33 before the interruption operation, and the end portion 213a contacts the inner surface of the end portion 243a. The end portion 213a has a shape that follows the shape of the inner surface of the end portion 243a, and contacts the inner surface of the end portion 243a over the entire circumferential direction. The end portion 213a has a tapered shape in which the inner diameter becomes smaller toward the top.

[0109] As described above, the interrupter 2a has a configuration in which the inner surface of the lower housing 230 is not exposed, and parts of the insulating resin members (the resin member 40 and the insulating member 210a) overlap in the circumferentially outward direction in the order of the insulating member 210a and the resin member 40.

[0110] (Embodiment 3) The configuration of the interrupter according to the present embodiment will be described below with reference to Figs. 9 to 10B. Fig. 9 is a cross-sectional view showing the configuration of interrupter 3 according to the present embodiment before interruption operation. Fig. 10A is a perspective view showing insulating member 310 according to the present embodiment as viewed from above. Fig. 10B is an exploded perspective view showing insulating member 310 according to the present embodiment as viewed from above.

[0111] In the following, differences from the first embodiment will be mainly described, and descriptions of the same or similar contents as those in the first embodiment will be omitted or simplified. The interrupting device 3 according to the present embodiment differs from the interrupting device 1 according to the first embodiment in that the insulating member 310 is composed of a plurality of members.

[0112] As shown in FIG. 9, the circuit breaker 3 includes an insulating member 310 instead of the insulating member 110 of the circuit breaker 1. As shown in FIG.

[0113] As shown in FIGS. 9 to 10B, the insulating member 310 has a first member 320 and a second member 330. The first member 320 and the second member 330 are separate members. Separate members here means that the first member 320 and the second member 330 are physically separated in an installed state. Separate members may mean that the first member 320 and the second member 330, which are separate members, are not fixed together. Separate members may also mean that the first member 320 and the second member 330 are manufactured separately in a manufacturing process.

[0114] The first member 320 covers the protruding portion 30a of the lower housing 30. The first member 320 covers, for example, the top of the protruding portion 30a. The first member 320 has a shape that follows the protruding portion 30a, and its cross-sectional shape is a U-shape rotated 180 degrees. The end of the first member 320 is a free end, and can be deformed by stress from the pusher 60.

[0115] The second member 330 covers the bottom 33 of the lower housing 30. The second member 330 covers the bottom 33, the side wall 34, and a part of the protrusion 30a. The second member 330 has a shape that mainly follows the bottom 33 and the side wall 34, and has a cross-sectional shape having two U-shaped portions.

[0116] The second member 330 is disposed so as to overlap, as viewed in the radial direction, a portion of the first member 320. This makes it possible to prevent the inner surface of the lower housing 230 from being exposed, even when the insulating member 310 is configured from the first member 320 and the second member 330, which are separate members.

[0117] The second member 330 is not in contact with the first member 320 at the overlapping portion. In other words, a gap 76 is provided between the first member 320 and the second member 330. The gap 76 is a narrow gap through which the high-temperature conductive gas generated by the arc during the interruption operation can be cooled while passing through, similar to the gap 74. In addition, since the second member 330 is not in contact with the first member 320, it is possible to suppress the stress that the first member 320 receives from the pusher 60 from being transmitted to the second member 330. In other words, it is possible to suppress the second member 330 from being damaged by the stress from the pusher 60.

[0118] The second member 330 has an end portion 113 , which constitutes an end portion of the insulating member 310 .

[0119] 10A and 10B, the first member 320 and the second member 330 are detachable. The first member 320 is, for example, simply placed on the second member 330. In other words, the first member 320 is simply placed on the second member 330 so as to cover an opening 331 formed at the top of the portion where the second member 330 protrudes toward the internal space.

[0120] (Method of manufacturing the cutoff device) Next, a manufacturing method of the interrupter according to each embodiment configured as described above will be described with reference to Fig. 11. Fig. 11 is a flow chart showing the manufacturing process of the interrupter 1 according to embodiment 1. Although Fig. 11 shows the manufacturing process of the interrupter 1 according to embodiment 1, the same applies to the interrupters 2, 2a, and 3 according to the other embodiments and modified examples.

[0121] 11, an upper housing 20 made of resin or metal is produced by resin molding, metal molding, or the like (S10), a lower housing 30 made of metal is produced by metal molding, or the like (S20), and an insulating member 110 is produced by resin molding, or the like (S30). Note that the order of steps S10 to S30 may be reversed, or at least two of them may be performed simultaneously.

[0122] Next, the upper housing 20 and the lower housing 30 are fixed (S40). For example, the upper housing 20 and the lower housing 30 are joined by welding or the like in a state in which the igniter 10, the resin member 40, the conductor 50, the pusher 60, the protective part 80, the elastic members 90, 92, 94, 96, and the insulating member 110 are housed inside. At this time, the upper housing 20 and the lower housing 30 are joined without any gaps in a state in which the insulating member 110 is housed so as to cover the inner surface of the lower housing 30. In this way, the above-mentioned breaking device 1 is produced.

[0123] (Other embodiments) Although the blocking device according to one or more aspects has been described above based on each embodiment, the present disclosure is not limited to these embodiments, etc. As long as it does not deviate from the gist of the present disclosure, various modifications conceivable by a person skilled in the art to this embodiment and forms constructed by combining components in different embodiments may also be included in the present disclosure.

[0124] The order of each step in the manufacturing method of the interrupter described above may be interchanged. Also, each step in the manufacturing method of the interrupter described in the above embodiment may be performed in one step or in separate steps. Note that "performed in one step" is intended to include each step being performed using one device, each step being performed consecutively, or each step being performed at the same location. Also, "separate steps" is intended to include each step being performed using separate devices, each step being performed at different times (e.g., different days), or each step being performed at different locations. [Industrial Applicability]

[0125] The present disclosure is useful for a circuit breaker arranged in an electric circuit or the like. [Explanation of symbols]

[0126] 1, 2, 2a, 3 Circuit Breaker 10 Igniter 11 Lid 11a opening 20 Upper case 21 Small diameter section 22 Connection 23 Large diameter section 30, 230 Lower housing (cover member) 30a Convex part 33 Bottom 34 Side wall 35 Fixed part 40 Resin parts 41 Buried section 42, 81 First cylinder part 43, 82 Second cylinder part 43a, 113, 213a, 243a end 43b Bottom end 50 Conductors 51 Separation section 52 Holding part 60 Pusher 61 Recess 62, 111, 211 Part 1 63, 112, 212, 212a 2nd part 70 space 72 Gap (space) 74, 76 Gap 80 Protection Department 83 Flange 90, 92, 94, 96 Elastic member 100 Fixing member 110, 210, 210a, 310 Insulating member 113a top end 230a Plate-shaped part 320 First member 330 Second member 331 Aperture d1, d2, d3 Inner diameter

Claims

1. An igniter for generating gas; a pusher located below the igniter; a conductor having a separation portion located below the pusher and a holding portion connected to the separation portion; A cover member located below the separation portion and made of metal; an insulating member located inside the cover member and below the separation portion; a resin member at least a portion of which is located inside the cover member and which holds the holding portion, The pusher is configured to separate the separation portion from the conductor under pressure of the gas generated by the igniter, the resin member and the insulating member cover an inner surface of the cover member, an end portion of the insulating member overlaps an end portion of the resin member, The lower end of the end portion of the resin member is located lower than the upper end of the end portion of the insulating member. Shutdown device.

2. The end of the insulating member is located between the end of the resin member and the cover member. The shutoff device according to claim 1 .

3. The end of the resin member is located between the end of the insulating member and the cover member. The shutoff device according to claim 1 .

4. the cover member has a protrusion located below the insulating member, The protrusion protrudes upward and is pressed by the pusher. The interrupter device according to any one of claims 1 to 3.

5. A gap is provided between the cover member and the insulating member, The gap is located below the insulating member. The interrupter device according to any one of claims 1 to 3.

6. A gap is provided between the cover member and the insulating member, The insulating member is a first portion covering an apex of the protrusion of the cover member; A second portion located below the first portion; having The second portion covers an inner surface of a bottom portion of the cover member, The gap is located between the bottom of the cover member and the lower surface of the second portion. The shutoff device according to claim 4.

7. The insulating member is a first member for covering a top portion of the protrusion of the cover member; A second member disposed so as to overlap a portion of the first member; having the second member covers an inner surface of a bottom portion of the cover member, The first member and the second member are separate members. The shutoff device according to claim 4.

8. The resin member is a buried portion in which the holding portion is buried; a first cylindrical portion in which the pusher is disposed; A second cylindrical portion is located below the first cylindrical portion and has a larger diameter than the first cylindrical portion; having The inner diameter of the second cylindrical portion is smaller than the inner diameter of the insulating member. The interrupter device according to any one of claims 1 to 3.

9. The resin member is a buried portion in which the holding portion is buried; a first cylindrical portion in which the pusher is disposed; A second cylindrical portion is located below the first cylindrical portion and has a larger diameter than the first cylindrical portion; having The inner diameter of the second cylindrical portion is smaller than the inner diameter of the insulating member. The shutoff device according to claim 6.

10. The resin member is a buried portion in which the holding portion is buried; a first cylindrical portion in which the pusher is disposed; A second cylindrical portion is located below the first cylindrical portion and has a larger diameter than the first cylindrical portion; having The inner diameter of the second cylindrical portion is smaller than the inner diameter of the insulating member. The shutoff device according to claim 7.

Images