Electric circuit breaker device

Abstract

To provide an electric circuit breaker capable of improving arc extinguishing performance of arc discharge without using a coolant.SOLUTION: According to an embodiment of the present disclosure, there is provided an electric circuit breaker device including: a housing having a cylindrical space therein; an igniter provided in an upper portion of the space; a projectile disposed in the space and configured to receive energy generated by an operation of the igniter and move downward in the space; and a conductor piece disposed penetrating the housing so as to cross the space and having a cut portion cut by the projectile configured to move in the space. The projectile has a slope on a surface that receives energy from the igniter for generating a force that rotates the projectile about a rotation axis in a direction in which the projectile moves in the space.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to pyrotechnic electrical circuit interruption devices. [Background technology]

[0002] Patent Document 1 discloses an electric circuit breaker that can quickly extinguish arc discharge when activated. This electric circuit breaker includes an igniter provided in a housing, a projectile that receives energy from the activated igniter and moves within the housing's accommodation space, a conductor piece that is disposed so that a portion thereof crosses the housing's accommodation space and whose portion to be excised is cut off by the moving projectile, and a coolant material for extinguishing arc discharge that occurs when the projectile cuts off the portion to be excised of the conductor piece. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-143090 Summary of the Invention [Problem to be solved by the invention]

[0004] The electric circuit breaker described in Patent Document 1 uses a coolant material as a coolant to suppress the occurrence of arc discharge when current is interrupted or to extinguish (extinguish) any arc discharge that occurs by removing and cooling the arc and the thermal energy of the excised portion that are generated when the projectile cuts off the portion of the conductor piece. This poses a problem in that the cost of the electric circuit breaker is high.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide an electric circuit interruption device that can improve the arc extinguishing performance during the interruption operation of an electric circuit without using a coolant material. [Means for solving the problem]

[0006] In order to solve the above problems, one aspect of the disclosed technology is an electrical circuit interrupter comprising: a housing having a cylindrical space inside; an igniter provided at the top of the space; a projectile that is disposed within the space and receives energy generated by activation of the igniter and moves through the space toward the bottom; and a conductor piece that penetrates the housing so as to cross the space and has a cut portion that can be cut by the projectile moving through the space, wherein the surface of the projectile that receives energy from the igniter is inclined so that, upon receiving the energy, a force that rotates the projectile with the direction of movement through the space as its axis of rotation. [Effects of the Invention]

[0007] According to the electric circuit breaker of the present disclosure, the projectile receives energy from the igniter and moves, rotating the cut portion of the conductor piece it cuts, thereby extending the arc (increasing the distance between the discharge points). This movement of the projectile can improve the arc extinguishing performance during the interruption of the electric circuit, even without using a coolant material. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view (partially transparent) of the structure of an electrical circuit interruption device according to an embodiment of the present disclosure; [Figure 2] Cross section of the electrical circuit breaker shown in Figure 1 along line AA [Figure 3] Cross-sectional image illustrating the operation of an electrical circuit breaker DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> [structure] Fig. 1 is a perspective view illustrating the schematic structure of an electrical circuit interruption device 10 according to an embodiment of the present disclosure. Fig. 2 is a schematic cross-sectional view of the electrical circuit interruption device 10 shown in Fig. 1 taken along line AA. The electrical circuit interruption device 10 illustrated in Figs. 1 and 2 includes an upper housing 100, a lower housing 200, an igniter 300, a projectile 400, and a conductor piece 500. Note that Fig. 1 illustrates the main components of the electrical circuit interruption device 10 in a see-through state to facilitate understanding of the structure.

[0010] This electrical circuit interrupter 10 is installed, for example, between a battery pack (battery) of an electric vehicle or the like and a charging inlet, and is used to immediately interrupt the large current flowing from the battery pack when, for example, a high-voltage ground fault occurs while the battery pack is being charged from an external charging station via the inlet.

[0011] The upper housing 100 is a truncated cone-shaped part made of an insulating material such as resin. Inside the upper housing 100, a cylindrical upper space 110 with a radius r is formed, penetrating from the top surface to the bottom surface (i.e., in the vertical direction). The upper space 110 does not have to penetrate the upper housing 100, and may be cylindrical in shape with only the bottom surface side, which is connected to the lower housing 200, open.

[0012] The lower housing 200 is a cylindrical component made of an insulating material such as resin. Inside the lower housing 200, a cylindrical lower space 210 having a radius r is formed from one bottom surface (hereinafter referred to as the "first bottom surface") that joins with the upper housing 100 to the other bottom surface (hereinafter referred to as the "second bottom surface") (i.e., in the vertical direction), with only the first bottom surface being open.

[0013] The upper housing 100 and the lower housing 200 are joined together with the bottom surface of the upper housing 100 in contact with the first bottom surface of the lower housing 200. Inside the upper housing 100 and the lower housing 200 joined together in this manner (hereinafter, these may be collectively referred to as the "housing"), a single cylindrical sealed space is formed spanning from the upper housing 100 to the lower housing 200, with the central axis of the upper space 110 and the central axis of the lower space 210 coinciding.

[0014] The shape of upper housing 100 is not limited to the above-described truncated cone shape, and the shape of lower housing 200 is not limited to the above-described cylindrical shape. As long as a single cylindrical sealed space is formed inside the housing after the two are joined, there are no particular restrictions on the external shape of each housing.

[0015] Igniter 300 is an electric igniter having an ignition unit containing gunpowder and a detonation unit for outputting an ignition signal to the ignition unit to detonate the gunpowder. Igniter 300 is activated when a predetermined abnormal state (such as a large current leak from the battery pack) is detected and the detonation unit outputs an ignition signal to the ignition unit. Igniter 300 is provided (held) at the upper end of upper space 110 of upper housing 100 in a direction such that energy generated by activation (detonation of gunpowder) is transmitted into upper space 110. When upper space 110 is formed to penetrate upper housing 100, placing igniter 300 at the upper end of upper space 110 forms a cylindrical space spanning from upper housing 100 to lower housing 200, and is thereby sealed.

[0016] The projectile 400 is a generally disk-shaped component made of an insulating material such as resin. The projectile 400 is disposed within the upper space 110 of the upper housing 100 and is held movably in the direction of the central axis (vertical direction) of the upper space 110. The projectile 400 is configured to be launched (fly) when the flat side of the projectile 400 facing the igniter 300 (hereinafter referred to as the "upper surface") receives energy generated when the igniter 300 is activated, and moves downward (away from the igniter 300) in the cylindrical space. The upper surface of the projectile 400 is provided with a predetermined slope 410. The slope 410 is shaped so that the upper surface of the projectile 400 receives energy generated when the igniter 300 is activated, and generates a force that rotates the projectile 400 around the direction of movement in the cylindrical space as the axis of rotation. In the example of FIG. 1, the projectile 400 is shown with a slope 410 that functions as four blades, but the shape of the slope 410 is not limited to this as long as the projectile 400 generates rotational force when it receives energy from the igniter 300.

[0017] The conductor piece 500 is a component for electrically connecting two devices, such as between an inlet and a battery pack, as a current path. An example of the conductor piece 500 is a substantially flat, rod-shaped bus bar (conductive bus bar) made of a conductive metal material. The conductor piece 500 is provided so as to penetrate the lower housing 200 and cross the lower space 210 (perpendicular to the central axis). The portion of the conductor piece 500 that crosses the lower space 210 corresponds to a portion (hereinafter referred to as a "cut portion") that is physically cut (broken) by the projectile 400 moving through the cylindrical space upon activation of the igniter 300. While FIG. 1 shows an example in which the conductor piece 500 is a flat, rod-shaped bus bar, the shape of the conductor piece 500 is not particularly limited as long as it has a cut portion.

[0018] [Operation] The operation of the electrical circuit interruption device 10 according to this embodiment will be described with further reference to Fig. 3. Fig. 3 is an image diagram of a cross section of the electrical circuit interruption device 10, illustrating the states of the projectile 400 and the conductor piece 500 in chronological order from when the igniter 300 is activated until the interruption of the electrical circuit is completed.

[0019] (1) Activation of igniter 300 FIG. 3(a) shows a vertical cross-sectional view of the electrical circuit breaker 10 in a state where the explosive unit outputs an ignition signal to the ignition unit, thereby initiating the detonation of the explosive and activating the igniter 300.

[0020] 3(a), when the igniter 300 is activated, the energy generated by the detonation of the gunpowder increases the internal pressure in the space between the igniter 300 and the projectile 400. This increase in internal pressure in the space applies a force to the projectile 400, pushing it downwards into the lower part of the lower housing 200.

[0021] (2) Launch of 400 projectiles FIG. 3(b) shows a vertical cross-sectional view of the electrical circuit interruption device 10 in a state where the projectile 400 has been pushed (fired) downward by the energy generated by the igniter 300.

[0022] As shown in (b) of Figure 3, as the internal pressure between the igniter 300 and the projectile 400 increases, the projectile 400, which was placed in the upper housing 100, is pushed downward toward the lower housing 200 while rotating, and moves within the cylindrical space until it reaches the conductor piece 500.

[0023] (3) Cutting the conductor piece 500 (c1) of Fig. 3 shows a vertical cross-sectional view of the electrical circuit interruption device 10 in a state immediately after the conductor piece 500 has been cut by the projectile 400. (c2) of Fig. 3 shows a positional relationship diagram (top view) of the conductor piece 500 in the state of (c1).

[0024] As shown in (c1) of Fig. 3, the projectile 400 that has reached the conductor piece 500 cuts the conductor piece 500 by the energy that it continues to receive from the igniter 300, separating the portion to be cut 510 (punching out the portion to be cut 510). At this time, the positional relationship between the portion to be cut 510 and the remaining portion (remaining portion) 520 of the conductor piece 500 immediately after the conductor piece 500 is cut is in a straight line when viewed from above the upper surface of the lower space 210, as shown in (c2) of Fig. 3. If this positional relationship remains even after the conductor piece 500 is cut, an arc discharge occurs between the portion to be cut 510 and the remaining portion 520, and the electrical circuit is still energized (the electrical path is maintained).

[0025] (4) Rotation of the cut part 510 Fig. 3(d1) shows a vertical cross-sectional view of the electrical circuit interruption device 10 in a state where the cut portion 510 cut by the projectile 400 hits the lower surface of the lower housing 200. Fig. 3(d2) shows a positional relationship diagram (top view) of the conductor piece 500 in the state of (d1).

[0026] As shown in (d1) of FIG. 3, even after the projectile 400 cuts the portion to be cut 510 from the conductor piece 500, the projectile 400 continues to receive energy from the igniter 300, causing the portion to be cut 510 to rotate together with the projectile 400 due to the effect of the inclination 410, and move until it hits the lower surface of the lower housing 200 (the bottom surface of the lower space 210). At this time, as shown in (d2) of FIG. 3, the positional relationship between the portion to be cut 510 that has reached the lower surface of the lower housing 200 and the remaining portion 520 of the conductor piece 500 is not in a straight line when viewed from above the lower space 210 due to the rotation. When this positional relationship occurs, the spatial distance (discharge distance) between the portion to be cut 510 and the remaining portion 520 increases, extending the arc and increasing the electrical circuit resistance, thereby consuming energy. As a result, the arc discharge is extinguished and terminated, and the electrical circuit is interrupted (completed interruption).

[0027] <Actions and Effects> As described above, according to the electrical circuit interruption device 10 of one embodiment of the present disclosure, a slope 410 is provided on the surface of the projectile 400 that receives energy from the igniter 300 (the surface that receives the increase in internal pressure) to generate a force that rotates the projectile 400 around the direction of movement through space as the rotation axis.

[0028] This inclination 410 allows the cut portion 510 of the conductor piece 500 punched by the projectile 400 to rotate together with the projectile 400, thereby extending the arc and improving the extinguishing performance of the arc discharge without increasing the size of the housing to increase the discharge distance or using a coolant material to improve cooling performance. [Industrial Applicability]

[0029] The electrical circuit breaker of the present disclosure is useful when it is desired to improve the arc extinguishing performance without using a coolant material. [Explanation of symbols]

[0030] 10 Electrical circuit breaker 100 Upper housing 110 Upper space 200 Lower housing 210 Lower space 300 igniter 400 projectiles 410 Incline 500 conductor pieces 510 Part to be cut 520 Residual site

Claims

[Claim 1] a housing having a cylindrical space therein; an igniter provided at an upper portion of the space; a projectile disposed in the space, receiving energy generated by activation of the igniter and moving downward through the space; a conductor piece that is provided through the housing so as to cross the space and has a cuttable portion that is cut by the projectile moving through the space; The projectile has a surface that receives the energy from the igniter that is inclined to generate a force that rotates the projectile around a rotation axis in the direction in which the projectile moves through the space by receiving the energy. Electrical circuit interrupter.

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