Electrical circuit switching device

Abstract

This electrical circuit switching device comprises: an ignitor provided to a housing; a cylindrical space formed inside the housing; an electroconductive projectile that is positioned at a first location in the cylindrical space in an initial state before actuation of the ignitor, and that is launched toward a launching direction due to energy of a combustion gas; a pair of first conductor pieces that are inserted in a state of being separated from each other at a second location further in the launching direction than the first location in the cylindrical space; and a support body that is arranged further in the launching direction than the first location in the cylindrical space and, at the second location, catches the projectile launched by actuation of the ignitor. When the ignitor is actuated and the projectile is launched, collision with the support body causes the projectile to deform, bringing the projectile and each of the pair of first conductor pieces into contact and causing the projectile to be locked by the pair of first conductor pieces, thereby switching a first electrical circuit from an interrupted state to an conducting state.

Description

Technical Field

[0001] The present invention relates to an electric circuit switching device.

Background Art

[0002] There is known a relay that protects an electrical device by switching a specific electric circuit from an open state to a conductive state when an abnormality occurs in the electrical device. Conventionally, as a relay, an electromagnetic relay that uses an electromagnet to switch the opening and closing of an electric circuit is known. However, in the conventional electromagnetic relay, since it takes time to switch to the conductive state, there is a problem that a malfunction such as a failure of the electrical device due to the influence of an overcurrent occurs.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology of the present disclosure provides a technology capable of shortening the time required for switching in an electric circuit switching device for switching a predetermined electric circuit from an open state to a conductive state.

Means for Solving the Problems

[0005] To solve the above problems, the electrical circuit switching device of this disclosure employs the following configuration. That is, the technology of this disclosure is an electrical circuit switching device that switches a predetermined first electrical circuit from an interrupted state to a conductive state when in operation, comprising: a housing; an igniter provided in the housing and releasing combustion gas when in operation; a cylindrical space formed within the housing and extending in one direction; a conductive projectile positioned at a first position in the cylindrical space in the initial state before the igniter is in operation, and launched in a predetermined firing direction along the cylindrical space by the energy of the combustion gas; and inserted at a distance from each other at a second position in the cylindrical space on the firing direction side of the first position. The electrical circuit switching device comprises a pair of first conductor pieces, each of which works together to form a part of a first electrical circuit, and a support positioned on the firing direction side of the first position in the cylindrical space, which receives the projectile fired by the operation of the igniter at a second position, wherein when the igniter is operated and the projectile is fired, the projectile deforms upon collision with the support, causing the projectile to come into contact with each of the pair of first conductor pieces and the projectile to become locked to the pair of first conductor pieces, thereby switching the first electrical circuit from an interrupted state to a conductive state.

[0006] Furthermore, in the electrical circuit switching device according to the present disclosure, the pair of first conductor pieces are inserted into the second position such that they are located on opposite sides of the projectile received by the support, and the support has a protrusion that projects toward the opposite side of the firing direction. A recess is formed on the end face of the projectile on the firing direction side, and when the igniter is activated and the projectile is fired, the projectile enters between the pair of first conductor pieces and the protrusion enters the recess, and the protrusion deforms the projectile by pushing open the recess, thereby widening the projectile in the direction of arrangement of the pair of first conductor pieces, and the projectile may be pressed between the pair of first conductor pieces.

[0007] Furthermore, in the electrical circuit switching device according to the present disclosure, the convex portion is formed in a triangular cross-section such that it widens in the direction of the arrangement of the pair of first conductor pieces as it moves from its tip toward the firing direction, and the recess is formed in a triangular cross-section such that it widens in the direction of the arrangement of the pair of first conductor pieces as it moves from its bottom toward the firing direction, and the widening angle of the convex portion may be set to be greater than the widening angle of the recess.

[0008] Furthermore, in the electrical circuit switching device according to the present disclosure, the pair of first conductor pieces are inserted into the second position such that they are located on opposite sides of the projectile received by the support, and the support has a protrusion that projects toward the opposite side of the firing direction. The projectile has a main body positioned at the first position in the initial state, and a pair of extensions arranged in the direction of the arrangement of the pair of first conductor pieces and extending from the main body in the firing direction. When the igniter is activated and the projectile is fired, the pair of extensions enter between the pair of first conductor pieces, and the protrusion enters between the pair of extensions, causing the protrusion to deform the projectile so as to bend the pair of extensions outward, resulting in a state where one of the pair of first conductor pieces is sandwiched between one of the pair of extensions and the main body, and the other of the pair of first conductor pieces is sandwiched between the other of the pair of extensions and the main body.

[0009] Furthermore, in the electrical circuit switching device according to this disclosure, a accommodating space may be formed between the protrusion and each of the pair of first conductor pieces, in which the pair of extended portions bent by the protrusion are accommodated.

[0010] Furthermore, the electrical circuit switching device according to the present disclosure is capable of switching a predetermined second electrical circuit from a conductive state to a disconnected state when in operation, and further comprises a pair of second conductor pieces inserted at a first position in the cylindrical space at a distance from each other, each of which cooperates to form a part of the second electrical circuit, wherein in the initial state, the pair of second conductor pieces are electrically connected via the projectile, causing the second electrical circuit to be in a conductive state, and when the igniter is activated and the projectile is fired, the electrical connection of the pair of second conductor pieces via the projectile is released, thereby switching the second electrical circuit from a conductive state to a disconnected state.

[0011] Furthermore, in the electrical circuit switching device according to this disclosure, in the initial state, the projectile is interposed between the pair of second conductor pieces and these are connected together, and the projectile may be separated from each of the pair of second conductor pieces by the energy of the combustion gas.

[0012] Furthermore, in the electrical circuit switching device according to this disclosure, the projectile is fitted into the inner wall of the cylindrical space, and the inner wall of the cylindrical space may be formed such that the cylindrical space narrows in width as it moves toward the firing direction.

[0013] Furthermore, the electrical circuit switching device according to this disclosure may further include a piston that is positioned in the cylindrical space between the igniter and the projectile and is launched in the firing direction by the energy of the combustion gas. [Effects of the Invention]

[0014] The electrical circuit switching device described herein makes it possible to shorten the time required to switch a predetermined electrical circuit from an interrupted state to a conductive state. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a longitudinal cross-sectional view showing the state of the switching device according to Embodiment 1 before operation. [Figure 2] Figure 2 is a front view of the projectile according to Embodiment 1. [Figure 3] Figure 3 is a bottom view of the projectile according to Embodiment 1. [Figure 4] Figure 4 is a front view of the support according to Embodiment 1. [Figure 5] Figure 5 is a top view of the support according to Embodiment 1. [Figure 6] Figure 6 is a longitudinal sectional view showing the state after the operation of the switching device according to Embodiment 1. [Figure 7] Figure 7 is a longitudinal sectional view showing the state before the operation of the switching device according to a modification of Embodiment 1. [Figure 8] Figure 8 is a longitudinal sectional view showing the state after the operation of the switching device according to a modification of Embodiment 1. [Figure 9] Figure 9 is a longitudinal sectional view showing the state before the operation of the switching device according to Embodiment 2. [Figure 10] Figure 10 is a front view of the projectile according to Embodiment 2. [Figure 11] Figure 11 is a bottom view of the projectile according to Embodiment 2. [Figure 12] Figure 12 is a front view of the support according to Embodiment 2. [Figure 13] Figure 13 is a top view of the support according to Embodiment 2. [Figure 14] Figure 14 is a longitudinal sectional view showing the state after the operation of the switching device according to Embodiment 2. [Figure 15] Figure 15 is a longitudinal sectional view showing the state before the operation of the switching device according to a modification of Embodiment 2. [Figure 16] Figure 16 is a longitudinal sectional view showing the state after the operation of the switching device according to a modification of Embodiment 2.

Mode for Carrying Out the Invention

[0016] An electrical circuit switching device according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that the configurations and combinations thereof in the embodiments are examples, and additions, omissions, substitutions, and other modifications can be made as appropriate without departing from the spirit of the present disclosure. This disclosure is not limited by the embodiments, but is limited only by the claims.

[0017] The electrical circuit switching device according to the embodiment of this disclosure is a device installed in electrical equipment (or electrical installation) for quickly switching between a conduction state and a disconnected state (also called a "non-conducting state") of an electrical circuit. For example, the electrical circuit switching device according to the embodiment can be used as a short-circuiting device to short-circuit a predetermined electrical circuit by urgently switching the electrical circuit from a "disconnected state" where the electrical circuit is disconnected to a "conducting state" where it is conductive when an abnormality occurs in the electrical equipment on which it is installed. Another example of use of the electrical circuit switching device according to the embodiment is that it can be used as a switching device that disconnects an electrical circuit that is in a conduction state while simultaneously enabling another electrical circuit that is in a disconnected state. In this specification, "conduction state" refers to a state in which an electrical circuit is electrically connected and can conduct current, and "disconnected state" refers to a state in which an electrical circuit is not electrically connected and cannot conduct current.

[0018] <Embodiment 1> Figure 1 is a longitudinal cross-sectional view illustrating the state of the electrical circuit switching device (hereinafter also simply referred to as the "switching device") 10 according to Embodiment 1 before operation. In Figure 1, a cross-section along the central axis A1 of the cylindrical space indicated by reference numeral 3 is shown. Hereinafter, the direction along the cylindrical space 3 (i.e., the axial direction of the cylindrical space 3 and the direction in which the cylindrical space 3 extends) will be referred to as the "upper direction" of the switching device 10, the top housing side indicated by reference numeral 11 will be referred to as the "upper side" in the up-down direction, and the housing body side indicated by reference numeral 12 will be referred to as the "lower side" in the up-down direction. Here, as shown in Figure 1, in the switching device 10, a pair of conductor pieces indicated by reference numerals 5A and 5B are arranged side by side. Hereinafter, the direction perpendicular to the axial direction of the cylindrical space 3 in which the pair of first conductor pieces 5A and 5B are arranged (aligned) will be referred to as the "arrangement direction of the pair of first conductor pieces 5A and 5B (or simply the arrangement direction)" or the "width direction". Figure 1 shows a cross-section parallel to the vertical direction and the direction of arrangement of the pair of first conductor pieces 5A and 5B. In this specification, the cross-section along the vertical direction of the switching device 10 is referred to as the "longitudinal section" of the switching device 10.

[0019] [Overall structure] As shown in Figure 1, the switching device 10 according to Embodiment 1 comprises a housing 1, an igniter 2, a cylindrical space 3, a projectile 4, a pair of first conductive pieces 5A and 5B, and a support 6. In the switching device 10, the state before the igniter 2 is activated is sometimes referred to as the "initial state." The switching device 10 shown in Figure 1 is in the initial state.

[0020] The installation target of the switching device 10 according to Embodiment 1 is not particularly limited. The switching device 10 prevents failures due to overcurrent, etc., by switching a predetermined electrical circuit, the first electrical circuit, from an interrupted state to a conductive state when there is an abnormality in an electrical circuit that constitutes an automobile, household electrical appliance, solar power generation system, etc., or in a system including the battery (e.g., lithium-ion battery) of said electrical circuit. Furthermore, the configuration and use of the first electrical circuit in this disclosure are not particularly limited. The first electrical circuit may be configured as a short-circuit circuit that intentionally short-circuits the current by switching to a conductive state for the purpose of dissipating the charge accumulated in the circuit or component to be protected. Alternatively, the first electrical circuit may be configured to bypass the faulty part by switching to a conductive state when any of the circuits constituting the electrical equipment, such as a semiconductor element or a battery cell, fails.

[0021] [housing] Housing 1 is an outer shell member that houses various parts and elements that constitute the switching device 10. Housing 1 is composed of a top holder 11 and a housing body 12 provided below the top holder 11.

[0022] The top holder 11 is made of metal, for example, and as shown in Figure 1, has a cylindrical mounting portion 111 that extends vertically and a flange portion 112 that extends radially outward from the lower end of the mounting portion 111. The upper end of the mounting portion 111 is an open end, and the igniter 2 is mounted inside the mounting portion 111 so as to airtightly close the open end.

[0023] The housing body 12 is an outer shell member formed of an insulating material such as synthetic resin. For example, the housing body 12 may be made of nylon, which is a type of polyamide synthetic resin. The housing body 12 according to Embodiment 1 has a top housing 121, a middle housing 122, and a bottom housing 123. The top housing 121 is formed in a cylindrical shape extending in the vertical direction, and its upper end is connected to the flange portion 112 of the top holder 11. The middle housing 122 is formed in a plate shape extending in the width direction, and is connected to the lower end of the top housing 121 with a pair of first conductor pieces 5A and 5B in between. The middle housing 122 has a through hole 122a through which the convex portion 62 of the support 6 described later passes. The bottom housing 123 is formed in a plate shape extending in the width direction, and is connected to the lower surface of the middle housing 122. The upper surface of the bottom housing 123 has a groove portion 123a that accommodates the base portion 61 of the support 6 described later.

[0024] As shown in Figure 1, the inner space of the top holder 11 and the inner space of the top housing 121 are connected, forming a cylindrical space 3 extending in one direction (in this example, vertically) within the housing 1. In the example shown in Figure 1, the housing 1 is constructed by combining the top holder 11, the top housing 121, the middle housing 122, and the bottom housing 123, but the technology of this disclosure is not limited to this embodiment.

[0025] Here, P1 in Figure 1 represents a predetermined first position in the extending direction of the cylindrical space 3 (i.e., the axial direction of the cylindrical space 3, which in this example is the vertical direction). The first position P1 is located below the igniter 2. Also, P2 in Figure 1 represents a predetermined second position in the extending direction of the cylindrical space 3 that is below the first position P1. At this time, as shown in Figure 1, since the inner wall 3a defining the cylindrical space 3 is formed in a tapered shape, the cylindrical space 3 is formed to narrow as it moves downwards. More specifically, the cylindrical space 3 is formed to narrow as it moves from the first position P1 to the second position P2.

[0026] [Igniter] The igniter 2 is an ignition device that releases combustion gas into the cylindrical space 3 when in operation, and has, for example, an ignition section containing gunpowder in a cup-shaped body. The igniter 2 can be formed, for example, by an electric igniter. The gunpowder contained in the ignition section of the igniter 2 is not particularly limited, but for example, ZPP (zirconium potassium perchlorate), ZWPP (zirconium tungsten potassium perchlorate), THPP (titanium hydride potassium perchlorate), lead tricinate, etc. may be used. The igniter 2 may also have a conductive pin (not shown) connected to a connector of an external power supply, and the gunpowder may be ignited by an operating current supplied to the conductive pin from the external power supply. This type of electric igniter is well known, and for example, an electric igniter provided in the inflator of an airbag device can be suitably used. As shown in Figure 1, the igniter 2 is provided in the housing 1 such that the ignition section faces into the cylindrical space 3. The igniter 2 releases the combustion gases generated by the burning of gunpowder into the cylindrical space 3 when it is activated.

[0027] [Projectile] The projectile 4 is formed from, for example, a conductive metal piece. As shown in Figure 1, the projectile 4 is housed within the cylindrical space 3 of the housing 1. In the initial state before the igniter 2 is activated, the projectile 4 is positioned at a first position P1 in the cylindrical space 3. As will be described in detail later, when the igniter 2 is activated, the projectile 4 is launched in a predetermined firing direction along the extending direction of the cylindrical space 3 by the energy of the combustion gas released from the igniter 2 into the cylindrical space 3. In this embodiment, the firing direction is set to the lower side in the vertical direction. The projectile 4 can also be called a "bullet".

[0028] Figure 2 is a front view of the projectile 4 according to Embodiment 1. Figure 3 is a bottom view of the projectile 4 according to Embodiment 1. As shown in Figures 1 to 3, the projectile 4 according to Embodiment 1 is formed in a plate shape extending in the width direction. The upper end surface 4a of the projectile 4 faces the ignition part of the igniter 2. Therefore, the upper end surface 4a of the projectile 4 is formed as a pressure-receiving surface that receives the energy (pressure of the combustion gas released from the igniter 2) generated by the operation of the igniter 2. When the igniter 2 is activated, the projectile 4 is launched in the firing direction by the energy (pressure) of the combustion gas received at the pressure-receiving surface. In addition, a recess 41 is formed on the lower end surface 4b, which is the end surface of the projectile 4 on the firing direction side. In this example, the recess 41 is provided in the center of the lower end surface 4b in the arrangement direction. Here, reference numeral 41a in Figure 2 indicates the most recessed part (bottom) of the recess 41. As shown in Figure 2, the recess 41 is formed in a triangular cross-section so as it widens in the direction of arrangement from its bottom 41a toward the firing direction. The recess 41 is formed by a pair of inclined surfaces 41b and 41c that slope to widen toward the firing direction. Here, the widening angle of the recess 41 is denoted as θ1. The widening angle θ1 is the angle made by the pair of inclined surfaces 41b and 41c.

[0029] Furthermore, the projectile 4 is conductive. The projectile 4 can be made of a metal such as copper (Cu), for example. However, the material of the projectile 4 is not particularly limited as long as it is conductive. The projectile 4 may be made of a metal other than copper, or it may be made of an alloy of copper and another metal.

[0030] As shown in Figure 1, the projectile 4 is fitted into the inner wall 3a of the cylindrical space 3. Here, as described above, the inner wall 3a of the cylindrical space 3 is tapered so that it narrows as the cylindrical space 3 moves toward the firing direction. Therefore, the inner wall 3a of the cylindrical space 3 acts as resistance, preventing the projectile 4 from moving toward the firing direction unless the ignition device 2 is activated. As a result, in the initial state before the ignition device 2 is activated, the projectile 4 is positioned at the first position P1 of the cylindrical space 3.

[0031] [First conductor piece] The pair of first conductor pieces 5A and 5B shown in Figure 1 are components of the switching device 10, and together they form a conductor that creates a part of a predetermined first electrical circuit in the electrical equipment to which the switching device 10 is applied. The pair of first conductor pieces 5A and 5B are also called bus bars. The pair of first conductor pieces 5A and 5B can be formed from a metal such as copper (Cu), for example. However, the material of the pair of first conductor pieces 5A and 5B is not particularly limited as long as it is a conductor. The pair of first conductor pieces 5A and 5B may be formed from a metal other than copper, or from an alloy of copper and another metal. Examples of metals other than copper that may be included in the pair of first conductor pieces 5A and 5B include manganese (Mn), nickel (Ni), and platinum (Pt). The first electrical circuit is formed by including the pair of first conductor pieces 5A and 5B and circuit components in other electrical equipment.

[0032] As shown in Figure 1, a pair of first conductor pieces 5A and 5B are inserted at a second position P2 in the cylindrical space 3, separated from each other. As described above, the second position P2 is defined as a position below (i.e., towards the launch direction) the first position P1 where the projectile 4 is positioned. The pair of first conductor pieces 5A and 5B are held in the housing 1, sandwiched from above and below by the top housing 121 and the middle housing 122, so that they are positioned extending along the direction of arrangement. Each of the first conductor pieces 5A and 5B has an inner end 51 inserted into the interior of the cylindrical space 3 and an outer end 52 exposed to the outside of the housing 1. Other conductors (e.g., lead wires) forming a first electrical circuit are connected to the outer ends 52 of each of the first conductor pieces 5A and 5B.

[0033] As shown in Figure 1, in the initial state before the igniter 2 is activated, the pair of first conductor pieces 5A and 5B configured as described above are separated from each other, so the first electrical circuit is maintained in a disconnected state. On the other hand, although the operation of the switching device 10 will be described later, when the igniter 2 is activated, the pair of first conductor pieces 5A and 5B become electrically connected to each other via the projectile 4, and the first electrical circuit switches from a disconnected state to a conductive state. Therefore, in the switching device 10 after activation, the projectile 4 can be said to function as a circuit component that constitutes the first electrical circuit.

[0034] [Support] The support 6 shown in Figure 1 is a member that receives the projectile 4 launched by the operation of the igniter 2 at the second position P2 and deforms the projectile 4 to lock it to the pair of first conductive pieces 5A and 5B. The support 6 can be made of a metal with higher strength (hardness) than the projectile 4, for example. The material of the support 6 is not particularly limited, but for example, if the material of the projectile 4 is copper (Cu), stainless steel such as SUS, which has higher hardness than copper, can be used.

[0035] As shown in Figure 1, the support 6 is positioned below (i.e., towards the launch direction) the first position P1 where the projectile 4 is positioned. In this example, the support 6 is positioned towards the launch direction above the second position P2. However, the technology of this disclosure is not limited to this embodiment. The support only needs to be positioned towards the launch direction above the first position, and may be positioned at the second position or at a position on the opposite side of the launch direction (above in this example) above the second position.

[0036] Figure 4 is a front view of the support 6 according to Embodiment 1. Figure 5 is a top view of the support 6 according to Embodiment 1. As shown in Figures 1, 4, and 5, the support 6 according to Embodiment 1 includes a base portion 61 and a convex portion 62. The base portion 61 is formed in the shape of a disc perpendicular to the vertical direction. The convex portion 62 protrudes upward from the top surface of the base portion 61 (i.e., opposite to the firing direction). In this example, the convex portion 62 is provided in the center of the base portion 61 in the arrangement direction. Here, reference numeral 62a in Figure 4 indicates the tip (top) of the convex portion 62. As shown in Figure 4, the convex portion 62 is formed in a triangular cross-section such that it widens in the arrangement direction from its tip 62a toward the firing direction. The convex portion 62 is formed by a pair of inclined surfaces 62b and 62c that are inclined to widen toward the firing direction. Here, the spreading angle of the convex portion 62 is denoted as θ2. The spreading angle θ2 is the angle made by the pair of inclined surfaces 62b and 62c. In this embodiment, the spreading angle θ2 of the convex portion 62 of the support 6 is set to be greater than the spreading angle θ1 of the concave portion 41 of the projectile 4.

[0037] As shown in Figure 1, the support 6 is held in the housing 1 with its base portion 61 housed in the groove portion 123a of the bottom housing 123 and its protrusion 62 inserted through the through hole 122a of the middle housing 122 and protruding into the cylindrical space 3. As a result, the protrusion 62 protrudes toward the opposite side of the firing direction at the lower end of the cylindrical space 3, that is, at the end of the cylindrical space 3 on the firing direction side. Also, as shown in Figure 1, the protrusion 62 is located between the pair of first conductive pieces 5A and 5B in the arrangement direction and faces the recess 41 of the projectile 4.

[0038] [Operation] Next, the operation of the switching device 10 will be described. Before the switching device 10 is activated, it is in the initial state shown in Figure 1, as described above. In the initial state shown in Figure 1, the pair of first conductor pieces 5A and 5B are separated from each other, so the first electrical circuit, which is partially formed by this pair of first conductor pieces 5A and 5B, is kept in an interrupted state. Furthermore, in the initial state, the projectile 4 is positioned at the first position P1 of the cylindrical space 3 with the inner wall 3a of the cylindrical space 3 fitted into the cylindrical space 3.

[0039] For example, when an abnormality occurs in the electrical equipment to which the switching device 10 applies, the switching device 10 operates to protect the electrical equipment and urgently switches the first electrical circuit from an interrupted state to a conductive state.

[0040] Here, the switching device 10 according to Embodiment 1 further includes an abnormality detection sensor (not shown) for detecting abnormal conditions in electrical equipment (e.g., vehicles, power generation equipment, energy storage equipment, etc.) on which the switching device 10 is installed, and a control unit (not shown) for controlling the operation of the igniter 2. The abnormality detection sensor may, for example, detect abnormal conditions such as overcurrent based on the current flowing through the circuit to be protected in the electrical equipment. Alternatively, the abnormality detection sensor may be, for example, an impact sensor, a temperature sensor, an acceleration sensor, a vibration sensor, etc., and may detect abnormal conditions such as accidents or fires based on impact, temperature, acceleration, and vibration in equipment such as vehicles. The control unit of the switching device 10 is, for example, a computer that can perform predetermined functions by executing a predetermined control program. The predetermined functions of the control unit can also be realized by corresponding hardware. For example, when an overcurrent flows through the circuit to be protected in the electrical equipment on which the switching device 10 is installed, the overcurrent is detected by the abnormality detection sensor. The abnormality information regarding the detected abnormal current is passed from the abnormality detection sensor to the control unit. For example, the control unit receives power from an external power supply (not shown) connected to the conductive pins of the igniter 2 based on the current value detected by the abnormality detection sensor, and operates the igniter 2. Here, overcurrent may be defined as a current value that exceeds a predetermined threshold set for the protection of the electrical circuit to be protected. Note that the abnormality detection sensor and control unit described above do not have to be included as components of the switching device 10, and may be included in a separate device, for example. Furthermore, the abnormality detection sensor and control unit are not essential components of the switching device 10.

[0041] When the igniter 2 of the switching device 10 is activated, combustion gases are released from the igniter 2 into the cylindrical space 3. The projectile 4 then receives the energy (pressure) of the combustion gases at its upper end surface 4a. The projectile 4 is then launched through the cylindrical space 3 in the launch direction (downward), using the energy of the combustion gases, which exceeds the drag force received from the inner wall 3a of the cylindrical space 3, as propulsion.

[0042] Figure 6 is a longitudinal cross-sectional view showing the state of the switching device 10 according to Embodiment 1 after operation. As shown in Figure 6, the projectile 4 launched from the first position P1 by the operation of the igniter 2 is received by the support 6 at the second position P2. Here, the pair of first conductive pieces 5A and 5B are inserted at the second position P2 so as to be on opposite sides of the projectile 4 that has been received by the support 6. Therefore, the launched projectile 4 enters between the pair of first conductive pieces 5A and 5B. Also, since the convex portion 62 of the support 6 and the concave portion 41 of the projectile 4 face each other, the convex portion 62 of the support 6 enters the concave portion 41 of the launched projectile 4. Therefore, the convex portion 62 of the support 6 collides with the inner wall (inclined surface 41b, 41c) of the concave portion 41. At this time, as described above, the spreading angle θ2 of the convex portion 62 of the support 6 is set to be larger than the spreading angle θ1 of the concave portion 41 of the projectile 4. Therefore, when the convex portion 62 of the support 6 collides with the inner wall of the recess 41, the projectile 4 deforms as the recess 41 is pushed open by the convex portion 62. As a result, the projectile 4 widens in the direction of alignment between the pair of first conductive pieces 5A and 5B, and the projectile 4 is sandwiched between the pair of first conductive pieces 5A and 5B. At this time, the widening force of the projectile 4 pushes each of the pair of first conductive pieces 5A and 5B outward. As a result, the projectile 4 is pressed between the pair of first conductive pieces 5A and 5B. Consequently, the projectile 4 is locked (fixed) to the pair of first conductive pieces 5A and 5B while in contact with each of them.

[0043] When the projectile 4 and the pair of first conductor pieces 5A and 5B come into contact, the pair of first conductor pieces 5A and 5B are electrically connected to each other via the conductive projectile 4. As a result, the first electrical circuit is switched from an interrupted state to a conductive state.

[0044] [effect] As described above, the switching device 10 according to Embodiment 1 comprises a housing 1, an igniter 2 provided in the housing 1 that releases combustion gas when in operation, a cylindrical space 3 formed inside the housing 1 and extending in one direction, a conductive projectile 4 positioned at a first position P1 in the cylindrical space 3 in the initial state before the igniter 2 is activated and launched in a predetermined firing direction along the cylindrical space 3 by the energy of the combustion gas, a pair of first conductive pieces 5A, 5B inserted at a distance from each other at a second position P2 in the cylindrical space 3 that is on the firing direction side of the first position P1, and each of the first conductive pieces 5A, 5B cooperate to form a part of a first electrical circuit, and a support 6 positioned on the firing direction side of the first position P1 in the cylindrical space 3 that receives the projectile 4 launched by the operation of the igniter 2 at the second position P2. In the switching device 10 according to Embodiment 1, when the igniter 2 is activated and the projectile 4 is launched, the projectile 4 deforms upon collision with the support 6, and the projectile 4 comes into contact with the pair of first conductor pieces 5A and 5B, respectively, and the projectile 4 becomes locked to the pair of first conductor pieces 5A and 5B, thereby switching the first electrical circuit from an interrupted state to a conductive state.

[0045] In other words, the switching device 10 according to Embodiment 1 uses the energy of combustion gas generated by igniting the gunpowder in the igniter 2 as an energy source to fire a conductive projectile 4, and the projectile 4 switches the electrical circuit from a disconnected state to a conductive state. By using pyrodynamics to operate the switching device 10, the time required to switch the electrical circuit can be shortened compared to, for example, a conventional electromagnetic relay. As a result, the electrical equipment on which the switching device 10 is installed can be quickly protected and failures can be avoided.

[0046] Furthermore, the switching device 10 according to Embodiment 1 is configured such that the projectile 4 deforms upon collision with the support 6, causing the projectile 4 to come into contact with the pair of first conductor pieces 5A and 5B, and the projectile 4 to be locked to the pair of first conductor pieces 5A and 5B. With such a switching device 10, since the projectile 4 received by the support 6 is locked to the pair of first conductor pieces 5A and 5B, it is possible to suppress the projectile 4 from returning in the opposite direction to the launch direction, i.e., toward the first position P1, due to the impact when the projectile 4 is received by the support 6. In addition, even if shock or vibration occurs in the switching device 10 after operation, it is possible to suppress the projectile 4 from coming off the pair of first conductor pieces 5A and 5B. As a result, with the switching device 10 according to Embodiment 1, the contact state between the projectile 4 and the pair of first conductor pieces 5A and 5B, and consequently the conductivity state of the first electrical circuit, can be maintained after operation.

[0047] Furthermore, the switching device 10 according to Embodiment 1 is configured such that the projectile 4 is deformed so that the convex portion 62 of the support 6 pushes open the recess 41, thereby widening the projectile 4 in the direction of the arrangement of the pair of first conductive pieces 5A and 5B, and the projectile 4 is pressed between the pair of first conductive pieces 5A and 5B. This allows the projectile 4 to be locked to the pair of first conductive pieces 5A and 5B. At this time, the switching device 10 according to Embodiment 1 can widen the recess 41 with the convex portion 62 by setting the spreading angle θ2 of the convex portion 62 to be greater than the spreading angle θ1 of the recess 41.

[0048] Furthermore, in the switching device 10 according to Embodiment 1, the projectile 4 is fitted into the inner wall 3a of the cylindrical space 3, and the inner wall 3a of the cylindrical space 3 is formed such that the cylindrical space 3 narrows as it moves toward the firing direction. This positions the projectile 4 to a first position in the initial state before the igniter 2 is activated, and prevents the projectile 4 from moving toward the firing direction before the igniter 2 is activated. The technology of this disclosure is not limited to this embodiment, and for example, the projectile may be positioned by press-fitting it into the inner wall of the cylindrical space.

[0049] [Modified example of Embodiment 1] The following describes a modified version of the switching device 10A according to Embodiment 1. In describing the switching device 10A, the differences from the switching device 10 will be the main focus, and details will be omitted for parts that are the same as those of the switching device 10, by using the same reference numerals. Figure 7 is a longitudinal cross-sectional view illustrating the state of the switching device 10A according to the modified version of Embodiment 1 before operation. Figure 8 is a longitudinal cross-sectional view illustrating the state of the switching device 10A according to the modified version of Embodiment 1 after operation. As shown in Figures 7 and 8, the switching device 10A according to the modified version of Embodiment 1 differs from the switching device 10 described above in that it further comprises a pair of second conductive pieces indicated by reference numerals 7A and 7B.

[0050] [composition] The switching device 10A according to a modification of Embodiment 1 protects electrical equipment by, when an abnormality occurs in the electrical equipment to be installed, by urgently switching a predetermined second electrical circuit from a conductive state to a disconnected state and urgently switching a predetermined first electrical circuit from a disconnected state to a conductive state. The target of installation of the switching device 10A according to a modification of Embodiment 1 is not particularly limited. Furthermore, the configuration and use of the second electrical circuit in this disclosure are not particularly limited. The second electrical circuit may be, for example, a circuit to be protected in the electrical equipment to which the switching device 10A is installed. For example, the target of installation of the switching device 10A may be an automobile, and the second electrical circuit may be a circuit for supplying power from the automobile's battery to external components. A modified version of Embodiment 1, the switching device 10A, may, for example, in the event of a failure of the battery control unit, switch the second electrical circuit from a conductive state to a disconnected state to cut off the power supply from the battery to the outside, thereby suppressing failure of external components due to overcurrent, and switch the first electrical circuit from a disconnected state to a conductive state to release the charge accumulated in the second electrical circuit, thereby protecting the second electrical circuit.

[0051] The pair of second conductor pieces 7A and 7B shown in Figure 7 are components of the switching device 10A, and together they form a conductor that creates a part of a predetermined second electrical circuit in the electrical equipment to which the switching device 10A is applied. The pair of second conductor pieces 7A and 7B are also called a bus bar. The second electrical circuit is formed by including the pair of second conductor pieces 7A and 7B and other circuit components in the electrical equipment. The material of the pair of second conductor pieces 7A and 7B is not particularly limited as long as it is a conductor, and the material used for the pair of first conductor pieces 5A and 5B described above (for example, copper, etc.) can be suitably used.

[0052] As shown in Figure 7, a pair of second conductor pieces 7A and 7B are inserted at a first position P1 in the cylindrical space 3, separated from each other. As described above, the first position P1 is the position where the projectile 4 is positioned. The pair of second conductor pieces 7A and 7B are held in the housing 1 in an orientation that extends along the direction of arrangement. Each of the pair of second conductor pieces 7A and 7B has its inner end 71 inserted into the interior of the cylindrical space 3 and its outer end 72 exposed to the outside of the housing 1. Other conductors (e.g., lead wires) that form a second electrical circuit are connected to the outer end 72 of each of the pair of second conductor pieces 7A and 7B.

[0053] As shown in Figure 7, in the initial state before the igniter 2 is activated, the projectile 4, positioned at the first position P1, is sandwiched between a pair of second conductive pieces 7A and 7B. At this time, the conductive projectile 4 and the inner ends 71 ​​of the pair of second conductive pieces 7A and 7B are in contact. Therefore, in the initial state, the pair of second conductive pieces 7A and 7B are electrically connected via the projectile 4.

[0054] Next, the operation of the switching device 10A according to a modified example of Embodiment 1 will be described. In the initial state shown in Figure 7, the pair of first conductor pieces 5A and 5B are separated from each other, so the first electrical circuit is kept in a disconnected state. On the other hand, in the initial state, the pair of second conductor pieces 7A and 7B are electrically connected via the projectile 4, so the second electrical circuit is in a conductive state. In other words, in the switching device 10A in the initial state, the projectile 4 also functions as a circuit component that constitutes the second electrical circuit.

[0055] For example, when an abnormality occurs in the electrical equipment to which the switching device 10A applies, the switching device 10A operates to protect the electrical equipment and urgently switches the first electrical circuit from a disconnected state to a conductive state, and the second electrical circuit from a conductive state to a disconnected state.

[0056] When the igniter 2 is activated, the projectile 4, which receives the energy (pressure) of the combustion gas at its upper end surface 4a, is launched in the firing direction (downward) within the cylindrical space 3, using the energy of the combustion gas as propulsion. As the projectile 4 moves from the first position P1 due to the activation of the igniter 2, the projectile 4 and the pair of second conductor pieces 7A and 7B become non-contact, as shown in Figure 8. This disconnects the electrical connection between the pair of second conductor pieces 7A and 7B via the projectile 4, and switches the second electrical circuit from a conductive state to a disconnected state. Then, similar to the switching device 10, the projectile 4, which is received at the second position P2 by the support 6, comes into contact with the pair of first conductor pieces 5A and 5B, and the first electrical circuit switches from a disconnected state to a conductive state. Furthermore, in the switching device 10A, similar to the switching device 10, the projectile 4, which has been deformed by collision with the support 6, becomes locked to the pair of first conductor pieces 5A and 5B, thus maintaining the conductivity of the first electrical circuit after operation.

[0057] [effect] As described above, the switching device 10A according to the modified embodiment 1 utilizes the energy of the combustion gas generated by the operation of the igniter 2 to urgently switch the second electrical circuit from a conductive state to a disconnected state and urgently switch the first electrical circuit from a disconnected state to a conductive state. In other words, the switching device 10A can switch the electrical circuit that becomes conductive from the second electrical circuit to the first electrical circuit by pyrodynamic drive. By using pyrodynamic drive, which utilizes a pyrotechnic device as the operating source for the switching device 10A, the time required to switch the electrical circuits can be shortened compared to, for example, a conventional electromagnetic relay. This allows for the rapid protection of electrical equipment on which the switching device 10A is installed and prevents malfunctions. Furthermore, the switching device 10A employs a configuration in which it fires a projectile 4 that electrically connects a pair of second conductor pieces 7A and 7B, and the fired projectile 4 electrically connects a pair of first conductor pieces 5A and 5B. This makes it possible to switch the second electrical circuit from a conductive state to a disconnected state and the first electrical circuit from a disconnected state to a conductive state with a single operation of the igniter 2.

[0058] In the switching device 10A according to a modified example of Embodiment 1, the projectile 4 and the pair of second conductor pieces 7A and 7B are each formed as separate components, but the technology of this disclosure is not limited thereto. For example, the projectile and the pair of second conductor pieces may each be formed as an integrated component (one component). In the switching device 10A, as in the modified example of Embodiment 2 described later, in the initial state before the igniter 2 is activated, the projectile 4 and the pair of second conductor pieces 7A and 7B may each be a conductor component formed as a single component, and when the igniter 2 is activated, the projectile 4 may be detached from the conductor component by the pressure of the combustion gas and move in the firing direction, thereby releasing the connection between the pair of second conductor pieces 7A and 7B via the projectile 4.

[0059] <Embodiment 2> Next, the switching device 20 according to Embodiment 2 will be described. Here, the differences from Embodiment 1 will be the main focus of the description, and components common to both the switching device 10 according to Embodiment 1 and this embodiment will be given the same reference numerals, thus omitting detailed explanations. Figure 9 is a longitudinal cross-sectional view illustrating the state of the switching device 20 according to Embodiment 2 before operation.

[0060] [composition] As shown in Figure 9, the switching device 20 according to Embodiment 2 differs from the switching device 10 according to Embodiment 1 in that it further includes a piston indicated by reference numeral 8. The projectile 4 according to Embodiment 2 also differs from the projectile 4 according to Embodiment 1 in that it has a pair of extended portions indicated by reference numerals 43A and 43B. The support body 6 according to Embodiment 2 also differs from the support body 6 according to Embodiment 1 in that it does not have a base portion 61. Furthermore, the pair of first conductor pieces 5A and 5B according to Embodiment 2 differ from the pair of first conductor pieces 5A and 5B according to Embodiment 1 in the shape of their inner ends 51.

[0061] Figure 10 is a front view of the projectile 4 according to Embodiment 2. Figure 11 is a bottom view of the projectile 4 according to Embodiment 2. As shown in Figures 9 to 11, the projectile 4 according to Embodiment 2 has a main body 42 and a pair of extensions 43A and 43B. The main body 42 is formed in a plate shape that extends in the width direction. The main body 42 is positioned at a first position P1 in the cylindrical space 3 in the initial state before the igniter 2 is activated. The pair of extensions 43A and 43B are arranged in the direction of the arrangement of the pair of first conductive pieces 5A and 5B and extend from the lower end surface 42b of the main body 42 in the firing direction. In this example, the pair of extensions 43A and 43B are located in the center of the main body 42 in the arrangement direction. Also, the pair of extensions 43A and 43B are formed in a piece-like (plate-like) shape perpendicular to the arrangement direction. However, the shape of the pair of extensions is not limited to this in the art of this disclosure. The pair of extensions may be, for example, rod-shaped.

[0062] Figure 12 is a front view of the support 6 according to Embodiment 2. Figure 13 is a bottom view of the support 6 according to Embodiment 2. As shown in Figures 9, 12 to 13, the support 6 according to Embodiment 2 has a protrusion 63 that projects upward (i.e., opposite to the firing direction). Here, reference numeral 63a in Figure 12 indicates the tip portion (top) of the protrusion 63. As shown in Figure 12, the protrusion 63 is formed in a triangular cross-section such that it widens in the direction of arrangement as it moves from its tip portion 63a toward the firing direction. The protrusion 63 is formed by a pair of inclined surfaces 63b and 63c that are inclined to widen toward the firing direction.

[0063] As shown in Figure 9, the support 6 according to Embodiment 2 is housed in a groove 123b formed in the bottom housing 123, and is held in the housing 1 with the protrusion 63 protruding into the cylindrical space 3. As a result, the protrusion 63 protrudes toward the opposite side of the firing direction at the end of the cylindrical space 3 on the firing direction side. Also, as shown in Figure 9, the protrusion 63 is located between a pair of first conductive pieces 5A and 5B in the arrangement direction. Furthermore, the tip 63a of the protrusion 63 is located between a pair of extending parts 43A and 43B of the projectile 4 in the arrangement direction.

[0064] The piston 8 is a component that pushes the projectile 4 in the firing direction so that the projectile 4 deforms more reliably when the igniter 2 is activated. As shown in Figure 9, the piston 8 is positioned in the cylindrical space 3 so as to be interposed between the igniter 2 and the projectile 4. The piston 8 is formed in a plate shape that extends in the width direction. However, the shape of the piston according to this disclosure is not limited to this. The upper end surface 8a of the piston 8 faces the ignition part of the igniter 2. Therefore, the upper end surface 8a of the piston 8 is formed as a pressure-receiving surface that receives the energy (pressure of the combustion gas released from the igniter 2) generated by the operation of the igniter 2. The lower end surface 8b of the piston 8 faces the upper end surface 42a of the main body 42 of the projectile 4. When the igniter 2 is activated, the piston 8 is launched in the firing direction by the energy (pressure) of the combustion gas received at the pressure-receiving surface. At that time, the lower end surface 8b of the piston 8 presses against the upper end surface 42a of the projectile 4.

[0065] The piston 8, like the support 6, can be made of a metal with higher strength (hardness) than the projectile 4, for example. The material of the piston 8 is not limited, but for example, if the material of the projectile 4 is copper (Cu), stainless steel such as SUS, which has higher hardness than copper, can be used.

[0066] As shown in Figure 9, the first conductor piece 5A according to Embodiment 2 has an inner end 51 that includes an inclined surface facing the inclined surface 63b of the protrusion 63 of the support 6. Similarly, the first conductor piece 5B according to Embodiment 2 has an inner end 51 that includes an inclined surface facing the inclined surface 63c of the protrusion 63 of the support 6. As a result, in the switching device 20 according to Embodiment 2, a storage space indicated by reference numeral 9 is formed between the protrusion 63 of the support 6 and the pair of first conductor pieces 5A and 5B, respectively. The volume of the storage space 9 is set so that it can accommodate the extended portion 43A and the extended portion 43B.

[0067] [Operation] Next, the operation of the switching device 20 according to Embodiment 2 will be described. In the initial state shown in Figure 9, the pair of first conductor pieces 5A and 5B are spaced apart from each other, so the first electrical circuit is maintained in an interrupted state. Also, in the initial state, the convex portion 63 of the support 6 and the pair of extending portions 43A and 43B of the projectile 4 are spaced apart. However, as long as the first electrical circuit is maintained in an interrupted state, the convex portion 63 and the pair of extending portions 43A and 43B may be in contact in the initial state.

[0068] When the igniter 2 is activated, the piston 8, which receives the energy (pressure) of the combustion gas at its upper end surface 8a, is propelled through the cylindrical space 3 in the firing direction (downward) using the energy of the combustion gas as thrust. At this time, the lower end surface 8b of the piston 8 presses against the upper end surface 42a of the projectile 4, thereby transmitting the energy of the combustion gas to the projectile 4 via the piston 8. The projectile 4 is propelled through the cylindrical space 3 in the firing direction, pushed by the piston 8, using the energy of the combustion gas as thrust, which exceeds the resistance force received from the inner wall 3a of the cylindrical space 3.

[0069] Figure 14 is a longitudinal cross-sectional view showing the state of the switching device 20 according to Embodiment 2 after operation. As shown in Figure 14, the projectile 4 launched from the first position P1 by the operation of the igniter 2 is received by the support 6 at the second position P2. Here, the pair of first conductive pieces 5A and 5B are inserted at the second position P2 so as to be on opposite sides of the projectile 4 that has been received by the support 6. Therefore, the pair of extended parts 43A and 43B of the launched projectile 4 enter between the pair of first conductive pieces 5A and 5B. Also, since the tip 63a of the convex part 63 of the support 6 is located between the pair of extended parts 43A and 43B of the projectile 4 in the direction of arrangement, the convex part 63 of the support 6 enters between the pair of extended parts 43A and 43B of the launched projectile 4. Therefore, the convex part 63 of the support 6 collides with the tips of the pair of extended parts 43A and 43B. At this time, as described above, the convex portion 63 is formed to widen in the direction of arrangement as it moves from the tip portion 63a toward the firing direction. Therefore, when the convex portion 62 of the support 6 collides with the tips of the pair of extension portions 43A and 43B, the pair of extension portions 43A and 43B deform to follow the convex portion 63, as shown in Figure 14. More specifically, the pair of extension portions 43A and 43B are bent outward so that the gap between them is widened. At this time, the pair of extension portions 43A and 43B bent by the convex portion 63 are housed in the housing space 9 formed between the convex portion 63 and the pair of first conductor pieces 5A and 5B. As a result, the first conductor piece 5A is held between the extension portion 43A and the main body portion 42 of the projectile 4, and the first conductor piece 5B is held between the extension portion 43B and the main body portion 42. As a result, as shown in Figure 14, the projectile 4 is locked (fixed) to the pair of first conductive pieces 5A and 5B while in contact with each of the two first conductive pieces 5A and 5B.

[0070] When the projectile 4 and the pair of first conductor pieces 5A and 5B come into contact, the pair of first conductor pieces 5A and 5B are electrically connected to each other via the conductive projectile 4. As a result, the first electrical circuit is switched from an interrupted state to a conductive state.

[0071] [effect] The switching device 20 according to Embodiment 2 can also obtain the same effects as the switching device 10 according to Embodiment 1 described above. In other words, by using pyrodynamic devices as the power source for the switching device 20, the time required to switch the electrical circuit can be shortened. Furthermore, since the projectile 4, which has been deformed by the collision with the support 6, is locked to the pair of first conductor pieces 5A and 5B, the conductivity of the first electrical circuit can be maintained after activation.

[0072] Furthermore, the switching device 20 according to Embodiment 2 is configured such that the convex portion 62 of the support 6 deforms the projectile 4 by bending the pair of extended portions 43A and 43B outward. The switching device 20 is configured such that, as the projectile 4 deforms, one of the pair of first conductor pieces 5A and 5B (first conductor piece 5A) is held between one of the pair of extended portions 43A and 43B (extended portion 43A) and the main body portion 42, and the other of the pair of first conductor pieces 5A and 5B (first conductor piece 5B) is held between the other of the pair of extended portions 43A and 43B (extended portion 43B) and the main body portion 42. This allows the projectile 4 to be locked to the pair of first conductor pieces 5A and 5B. Furthermore, in the switching device 20 according to Embodiment 2, a accommodating space 9 is formed between the convex portion 63 of the support 6 and each of the pair of first conductor pieces 5A and 5B, in which the pair of extended portions 43A and 43B bent by the convex portion 63 are accommodated, so that the convex portion 62 of the support 6 can bend the pair of extended portions 43A and 43B outward. In addition, in the technology according to this disclosure, the projectile may be provided with three or more extended portions. That is, in the embodiment in which the projectile is locked to the pair of first conductor pieces by bending the extended portions, the projectile only needs to have at least one pair (two) of extended portions.

[0073] Furthermore, the switching device 20 according to Embodiment 2 is positioned in a cylindrical space 3 so as to be interposed between the igniter 2 and the projectile 4, and includes a piston 8 that is launched in the firing direction by the energy of the combustion gas. With this configuration, the projectile 4 can be deformed more reliably by pushing the projectile 4 in the firing direction with the piston 8 when the igniter 2 is activated. Note that the switching device 20 according to Embodiment 2 does not necessarily have to include a piston 8. The switching device 20 may not include a piston 8 and may be configured such that the projectile 4 is launched by directly receiving the pressure of the combustion gas, as in the switching device 10 according to Embodiment 1. [Modified version of Embodiment 2] The following describes a modified version of the switching device 20A according to Embodiment 2. In describing the switching device 20A, the differences from the switching device 20 will be the main focus, and details will be omitted for parts that are the same as those of the switching device 20, by using the same reference numerals. Figure 15 is a longitudinal cross-sectional view illustrating the state of the switching device 20A according to the modified version of Embodiment 2 before operation. Figure 16 is a longitudinal cross-sectional view illustrating the state of the switching device 20A according to the modified version of Embodiment 2 after operation. As shown in Figures 15 and 16, the switching device 20A according to the modified version of Embodiment 2 differs from the switching device 20 described above in that it further comprises a pair of second conductor pieces 7A and 7B, similar to the switching device 10A according to the modified version of Embodiment 1. In addition, unlike the switching device 20 described above, the inner wall 3a of the cylindrical space 3 in the switching device 20A is not tapered, and the width of the cylindrical space 3 is constant along the firing direction.

[0074] [composition] The switching device 20A, a modified version of Embodiment 2, protects the electrical equipment by, in the same manner as the switching device 10A described above, by urgently switching a predetermined second electrical circuit from a conductive state to a disconnected state and urgently switching a predetermined first electrical circuit from a disconnected state to a conductive state when an abnormality occurs in the electrical equipment to be installed.

[0075] As shown in Figure 15, in the initial state of the switching device 20A, the projectile 4 and the pair of second conductor pieces 7A and 7B are each formed as a single component. More specifically, a conductor component 101, in which the projectile 4 and the pair of second conductor pieces 7A and 7B are integrated, is held in the housing 1 at the first position P1. The material of the conductor component 101 is not particularly limited as long as it is a conductor, and the material used for the pair of first conductor pieces 5A and 5B described above (for example, copper, etc.) can be suitably used. In the conductor component 101, the projectile 4 is sandwiched between the pair of second conductor pieces 7A and 7B, and the main body 42 of the projectile 4 and the inner ends 71 ​​of the pair of second conductor pieces 7A and 7B are connected. Therefore, in the initial state, the projectile 4 is positioned at the first position P1, and the pair of second conductor pieces 7A and 7B are electrically connected via the projectile 4.

[0076] Reference numeral 102 denotes a connection portion to which the projectile 4 and the second conductive pieces 7A and 7B are connected, respectively. The connection portion 102 may be made weaker than other parts by, for example, providing a notch in the surface of the member by beveling, thereby making the thickness of the connection portion 102 thinner than other parts.

[0077] [Operation] Next, the operation of the switching device 10A according to a modified example of Embodiment 1 will be described. In the initial state shown in Figure 15, the pair of first conductor pieces 5A and 5B are separated from each other, so the first electrical circuit is kept in an interrupted state. On the other hand, in the initial state, the pair of second conductor pieces 7A and 7B are electrically connected via the projectile 4, so the second electrical circuit is in a conductive state.

[0078] When the igniter 2 is activated, the piston 8, which receives the energy (pressure) of the combustion gas at its upper end surface 8a, is propelled through the cylindrical space 3 in the firing direction (downward) using the energy of the combustion gas as thrust. At this time, the lower end surface 8b of the piston 8 presses against the upper end surface 42a of the projectile 4, pushing through the connection portion 102 of the conductor component 101, and separating the projectile 4 from the conductor component 101. The projectile 4, separated from the conductor component 101, is propelled through the cylindrical space 3 in the firing direction while being pushed by the piston 8, using the energy of the combustion gas transmitted via the piston 8 as thrust. As the projectile 4 moves from the first position P1 due to the operation of the igniter 2, the projectile 4 and the pair of second conductor pieces 7A and 7B become non-contact, as shown in Figure 16. As a result, the electrical connection between the pair of second conductor pieces 7A and 7B via the projectile 4 is released, and the second electrical circuit is switched from a conductive state to a disconnected state. Then, similar to the switching device 20, the first electrical circuit is switched from an interrupted state to an conductive state when the projectile 4, which is received at the second position P2 by the support 6, comes into contact with the pair of first conductive pieces 5A and 5B. Furthermore, in the switching device 20A, similar to the switching device 20, the projectile 4, which has been deformed by the collision with the support 6, becomes locked to the pair of first conductive pieces 5A and 5B, so that the conductive state of the first electrical circuit is maintained after operation.

[0079] [effect] As described above, the switching device 20A according to the modified embodiment 2 uses pyrodynamic drive, which utilizes a pyrotechnic device as the power source for the switching device 20A, thereby shortening the time required for switching the electrical circuit.

[0080] Furthermore, the switching device 20A, a modified example of Embodiment 2, incorporates a conductive component 101 into the housing 1 in which the main body 42 of the projectile 4 is interposed between a pair of second conductive pieces 7A and 7B, and these are integrally connected. This configuration uses the energy of the combustion gas released from the igniter 2 when the igniter 2 is activated to separate the projectile 4 from each of the pair of second conductive pieces 7A and 7B. This allows for a smooth switching of the second electrical circuit, which is partially formed by the pair of second conductive pieces 7A and 7B, from a conductive state to a disconnected state when the igniter 2 is activated. Additionally, the switching device 20A employs a configuration in which a piston 8, positioned in a cylindrical space 3 so as to be interposed between the igniter 2 and the projectile 4, is launched in the firing direction by the energy of the combustion gas, thereby enabling more reliable separation of the projectile 4 from each of the pair of second conductive pieces 7A and 7B.

[0081] In addition, in the switching device 20A, the projectile 4 and the pair of second conductor pieces 7A and 7B may be separate components, as in the switching device 10A according to the modified embodiment 1 described above. For example, in the initial state of the switching device 20A, the projectile 4 may be positioned at the first position P1 by fitting it into the inner wall 3a of the cylindrical space 3, and the second electrical circuit may be made conductive by bringing the projectile 4 and the pair of second conductor pieces 7A and 7B into contact.

[0082] <Other> The embodiments of the electrical circuit switching device according to this disclosure have been described above, but each embodiment disclosed herein can be combined with any other features disclosed herein. For example, in Embodiment 1, a piston 8 may be provided so as to be interposed between the igniter 2 and the projectile 4. [Explanation of symbols]

[0083] 1: Housing 2:Igniter 3: Cylindrical space 4: Projectile 5A, 5B: A pair of first conductor pieces 6:Support 7A, 7B: A pair of second conductor pieces 8: Piston 9: Containment space 10, 10A, 20, 20A: Electrical circuit switching device

Claims

1. An electrical circuit switching device that switches a predetermined first electrical circuit from an interrupted state to a conductive state when in operation, Housing and An igniter provided in the housing, which releases combustion gas when in operation, A cylindrical space formed within the housing and extending in one direction, The igniter is positioned at a first position in the cylindrical space in its initial state before operation, and a conductive projectile is launched in a predetermined firing direction along the cylindrical space by the energy of the combustion gas, A pair of first conductor pieces are inserted at a distance from each other at a second position in the cylindrical space that is on the firing direction side of the first position, and each of the first conductor pieces cooperates to form a part of the first electrical circuit, A support positioned on the firing direction side of the first position in the cylindrical space, which receives the projectile fired by the operation of the igniter at the second position, Equipped with, When the igniter is activated and the projectile is fired, the projectile deforms upon impact with the support, causing the projectile to come into contact with each of the pair of first conductor pieces and the projectile to become locked to the pair of first conductor pieces, thereby switching the first electrical circuit from an interrupted state to a conductive state. Electrical circuit switching device.

2. The pair of first conductive pieces are inserted into the second position such that they are located on opposite sides of the projectile that is received by the support, The support has a protrusion that projects toward the opposite side of the firing direction, A recess is formed on the end face of the projectile on the side facing the launch direction. When the igniter is activated and the projectile is fired, the projectile enters between the pair of first conductor pieces, and the protrusion enters the recess, and the protrusion deforms the projectile by pushing open the recess, causing the projectile to widen in the direction of the arrangement of the pair of first conductor pieces, and the projectile becomes pressed between the pair of first conductor pieces. The electrical circuit switching device according to claim 1.

3. The aforementioned protrusion is formed in a triangular cross-section such that it widens in the direction of the arrangement of the pair of first conductive pieces as it moves from its tip toward the firing direction. The recess is formed in a triangular cross-section such that it widens in the direction of the arrangement of the pair of first conductive pieces as it extends from its bottom toward the firing direction. The spreading angle of the convex portion is set to be greater than the spreading angle of the concave portion. The electrical circuit switching device according to claim 2.

4. The pair of first conductive pieces are inserted into the second position such that they are located on opposite sides of the projectile that is received by the support, The support has a protrusion that projects toward the opposite side of the firing direction, The projectile has a main body positioned at the first position in the initial state, and a pair of extending portions arranged in the direction of the arrangement of the pair of first conductive pieces and extending from the main body in the direction of launch. When the igniter is activated and the projectile is fired, the pair of extensions enter between the pair of first conductor pieces and the protrusion enters between the pair of extensions, and the protrusion deforms the projectile by bending the pair of extensions outward, so that one of the pair of first conductor pieces is held between one of the pair of extensions and the main body, and the other of the pair of first conductor pieces is held between the other of the pair of extensions and the main body. The electrical circuit switching device according to claim 1.

5. Between the protrusion and each of the pair of first conductor pieces, a accommodating space is formed in which the pair of extended portions bent by the protrusion are housed. The electrical circuit switching device according to claim 4.

6. The aforementioned electrical circuit switching device is further capable of switching a predetermined second electrical circuit from a conductive state to a disconnected state when in operation, The cylindrical space further comprises a pair of second conductor pieces inserted at the first position, separated from each other, each of which cooperates to form a part of the second electrical circuit, In the initial state described above, the pair of second conductor pieces are electrically connected via the projectile, causing the second electrical circuit to be in a conductive state. When the igniter is activated and the projectile is fired, the electrical connection between the pair of second conductor pieces via the projectile is released, thereby switching the second electrical circuit from a conductive state to a disconnected state. An electrical circuit switching device according to any one of claims 1 to 5.

7. In the initial state described above, the projectile is interposed between the pair of second conductive pieces and these are connected as a whole, and the projectile is separated from each of the pair of second conductive pieces by the energy of the combustion gas. The electrical circuit switching device according to claim 6.

8. The projectile is fitted into the inner wall of the cylindrical space, The inner wall of the cylindrical space is formed such that the cylindrical space narrows in width as it moves toward the firing direction. An electrical circuit switching device according to any one of claims 1 to 6.

9. The system further comprises a piston positioned in the cylindrical space between the igniter and the projectile, which is launched in the firing direction by the energy of the combustion gases. An electrical circuit switching device according to any one of claims 1 to 8.

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