An arc extinguishing structure for a fuse

Abstract

An arc extinguishing structure of an incentive fuse includes a shell, an excitation source, a piston, a conductor, a fuse body, an arc extinguishing medium, a fuse body breaking assembly arranged in the shell, the piston is arranged corresponding to the conductor and the fuse body breaking assembly, the fuse body is connected in parallel with the conductor, a cutting narrow neck is arranged on the fuse body, the cutting narrow neck is arranged in the arc extinguishing medium, and the fuse body passes through the fuse body breaking assembly; a gas generating substance is arranged at any position or combined positions of the fuse body breaking assembly on one side or both sides of the cutting narrow neck, close to the fuse body, or at a position where the fuse body breaking assembly close to the fuse body contacts the shell; when the excitation source triggers to release high-pressure gas to drive the piston to move, the piston breaks the conductor, the fuse body breaking assembly is driven to move to break the fuse body from the cutting narrow neck, and the gas generating substance releases a large amount of gas at high temperature to participate in arc extinguishing. By arranging the gas generating substance, the arc extinguishing speed is improved and no tail is left.

Description

Technical Field

[0001] This invention relates to the fields of power control, electric vehicles, energy storage, and photovoltaics, and in particular to an arc-extinguishing structure for activating fuses. Background Technology

[0002] Existing induced fuses mainly consist of an excitation source (gas generator), a piston, a conductor, a fuse element connected in parallel with the conductor, an arc-extinguishing medium, and a fuse element disconnection assembly. The piston is positioned corresponding to the conductor and the fuse element disconnection assembly, while the fuse element disconnection assembly is positioned corresponding to the fuse element. The fuse element has a fusing neck for fusing and a cutting neck that is mechanically disconnected by the fuse element disconnection assembly. The fusing neck and the cutting neck are located in the arc-extinguishing medium. The end of the excitation source that releases high-pressure gas corresponds to the piston or is positioned through a flow channel corresponding to the piston. Its operating principle is as follows: the excitation source is triggered by a trigger signal, releasing high-pressure gas as the driving force to drive the piston to move towards the conductor and the fuse element disconnection assembly. The piston's movement first cuts off the conductor, and then the piston's kinetic energy mechanically disconnects the fuse element. When the fault current is large, the rate of temperature rise at the fuse neck is higher than the rate at which the fuse is mechanically disconnected. The fuse first melts at the fuse neck and is then mechanically disconnected from the cutting neck by the fuse element disconnection assembly. Regardless of the method of disconnection, the break point is located in the arc-extinguishing medium. When the fuse first melts at the fuse neck, the narrow section primarily participates in arc extinguishing, resulting in a short arc duration and rapid arc extinguishing. When the fault current is small, the rate of temperature rise at the fuse neck is lower than the rate at which the fuse is mechanically disconnected. The fuse is then disconnected from the cutting neck by the fuse element disconnection assembly. In this case, the cutting neck primarily participates in arc extinguishing, which can easily lead to current tailing and a longer arc duration, resulting in a longer breaking time. This fails to meet customer requirements for breaking time and poses a potential hazard to the interlocking logic control of subsequent circuits in the battery pack, posing a significant electrical safety risk. How to shorten the breaking time in this situation is a technical problem that needs to be solved. Summary of the Invention

[0003] The purpose of this invention is to shorten the breaking time and improve the arc extinguishing capability by setting a gas-generating substance in the fracture surface formed by the mechanical breaking of the fuse, and using the high temperature of the electric arc to release high-pressure gas from the gas-generating substance.

[0004] To achieve the above objectives, the present invention provides a fuse extinguishing structure, comprising a housing, and an excitation source, a piston, a conductor, a fuse element, an arc-extinguishing medium, and a fuse element disconnection assembly disposed within the housing. The piston is disposed corresponding to the conductor and the fuse element disconnection assembly. The fuse element is connected in parallel to the conductor and has a cutting neck disposed within the arc-extinguishing medium. The fuse element passes through the fuse element disconnection assembly. A gas-generating substance is disposed at one or both sides of the cutting neck, on the fuse element near the fuse element, or at any or a combination of locations near the contact point between the fuse element disconnection assembly and the housing. When the excitation source is triggered, it releases high-pressure gas to drive the piston to displace. After the piston disconnects the conductor, it drives the fuse element disconnection assembly to displace from the cutting neck and disconnect the fuse element. The gas-generating substance releases a large amount of gas at high temperature to participate in arc extinguishing.

[0005] Preferably, the melt cutting assembly includes an upper push rod and a lower push rod nested together, with the melt cutting element passing between the upper push rod and the lower push rod.

[0006] Preferably, the gap between the upper push rod and the housing is filled with the gas-generating substance.

[0007] Preferably, the gas-generating substance is provided at a position on the upper push rod near the fuse.

[0008] Preferably, a groove is provided on the outer peripheral surface of the upper push rod near the fuse, and the groove is filled with the gas-generating substance.

[0009] Preferably, the gas-generating substance is disposed on the upper push rod by means of a two-color mold or secondary injection molding.

[0010] Preferably, the fuse body is provided with multiple rows of parallel cutting slits, and the gas-generating substance is respectively provided on one or both sides of each row of cutting slits.

[0011] Preferably, the cutting neck is formed by connecting two variable cross-section structures of different widths, and the gas-producing substance is disposed on the variable cross-section structure with the larger width.

[0012] Preferably, a second recess for nesting is provided on the end of the lower push rod facing the upper push rod, and positioning holes are spaced apart in the second recess. A nesting protrusion is provided on the end of the upper push rod facing the lower push rod, and a positioning post is provided on the end face of the protrusion facing the lower push rod corresponding to the positioning hole. A first recess is provided on the fuse body corresponding to the second recess, and a through hole is provided in the first recess corresponding to the positioning post. The first recess of the fuse body is located in the second recess of the lower push rod, and the positioning post of the upper push rod passes through the through hole of the fuse body and is inserted into the positioning hole in the lower push rod, thereby clamping and fixing the fuse body between the upper push rod and the lower push rod.

[0013] Preferably, the gas-generating substance is an elastic rubber, melamine, or plastic.

[0014] The arc-extinguishing structure of the excitation fuse of the present invention provides gas-generating substances in the cutting neck of the fuse body, the gap between the fuse cutting assembly and the shell, and on the fuse cutting assembly. When the fuse body breaks and the arc is generated at high temperature, the gas-generating substances release a large amount of gas under the arc erosion, carrying away the heat generated by the arc and dissipating it away from the break, so that the arc temperature drops quickly, which is conducive to the rapid extinguishing of the arc without trailing.

[0015] Simultaneously, as the fuse disconnecting assembly moves away from the fuse break, the gas-generating material moves with the fuse disconnecting part and rubs against the arc-extinguishing medium. As the gas-generating material vaporizes, it forms multiple slits on the arc-extinguishing medium, allowing more arc-extinguishing medium to participate in arc extinguishing. This increases the arc voltage through the slits, accelerates the rate at which the current drops to zero, and further speeds up arc extinction. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a structure in which the gap between the melt-breaking component and the outer shell is filled with a gas-generating substance.

[0017] Figure 2 This is a schematic diagram of a fuse structure without any gas-generating material.

[0018] Figure 3 This is a schematic diagram of the fusible link structure for setting up the gas-generating substance.

[0019] Figure 4 This is a schematic diagram of the upper push rod structure.

[0020] Figure label:

[0021] 1. Outer shell, 3. Fusible element, 4. Arc extinguishing medium, 5. Upper push rod, 6. Lower push rod, 301. First groove, 302. Cutting neck (302, 303), variable cross-section structure (302a, 302b), gas-generating substance (304, 7, 8), 501. Protruding ridge, 502. Detailed Implementation

[0022] The arc-extinguishing structure of the excitation fuse of the present invention includes an excitation source, a piston, a conductor, a fuse element, an arc-extinguishing medium, and a fuse element disconnection assembly. The piston is positioned corresponding to the conductor and the fuse element disconnection assembly. The fuse element is connected in parallel to the conductor and has a cutting neck disposed in the arc-extinguishing medium. The fuse element passes through the fuse element disconnection assembly. A gas-generating substance is disposed at one or both sides of the cutting neck, on the fuse element disconnection assembly near the fuse element, or at any or a combination of several positions near the contact point between the fuse element disconnection assembly and the housing. When the excitation source is triggered, it releases high-pressure gas to drive the piston to move. After the piston disconnects the conductor, it drives the fuse element disconnection assembly to move and disconnect the fuse element from the cutting neck. The gas-generating substance releases a large amount of gas at high temperature to participate in arc extinguishing.

[0023] The following describes preferred embodiments in detail with reference to the accompanying drawings. The directional terms used are for reference only and do not constitute a limitation on the technical solution of this invention.

[0024] Excite the fuse arc extinguishing structure, see Figure 1 The device includes a housing 1, within which are disposed an excitation source (not shown), a piston (not shown), a conductor (not shown), a fuse element 3, an arc-extinguishing medium 4, and a fuse disconnection assembly. The conductor passes through the housing 1, with both ends located outside the housing 1 as connection terminals for activating the fuse. The fuse element 3 is connected in parallel to the conductor and is located on the side of the conductor away from the initial position of the piston. An arc-extinguishing cavity is provided in the housing 1, and the fuse element 3 passes through the arc-extinguishing cavity, which is filled with the arc-extinguishing medium 4.

[0025] A displacement channel is provided in the outer casing 1 to accommodate the melt-breaking assembly and to allow displacement of the piston's impact head. The fusible link 3 passes through the displacement channel. The melt-breaking assembly is positioned within the displacement channel corresponding to the fusible link.

[0026] Fuse 3, see Figure 2 and Figure 3The fuse element 3 is provided with a first groove 301 nested within the fuse breaking assembly. Several parallel cutting necks (302, 303) are spaced apart along the width of the fuse element 3. Cutting necks (302, 303) are respectively provided on both sides of the first groove 301. The cutting necks are stress concentration structures, facilitating mechanical breakage. The cutting neck 302 on one side of the first groove 301 is configured as a two-section variable cross-section structure (302a, 302b), with the width of variable cross-section structure 302a greater than the width of variable cross-section structure 302b. When the fuse breaking assembly, carrying the held fuse element, shifts, it can be broken at the narrowest point of the cutting neck, forming a fracture. Gas-generating material 304 is provided on both sides or one side along the length direction at the narrowest point of the cutting neck, bringing the gas-generating material close to the fracture surface of the fuse element 3. The gas-generating material can be applied to the fuse element 3 by coating, spraying, or impregnation. Gas-producing substances are those that can release a large amount of gas under the high temperature of an electric arc, such as elastic rubber, melamine, or plastics.

[0027] See the melt disconnect assembly. Figure 1 and Figure 4 The system includes an upper push rod 5 and a lower push rod 6 nested together. The lower push rod 6 has a second recessed groove on its end face facing the upper push rod 5, and positioning holes (not shown) are spaced along the bottom of the second recessed groove. The upper push rod 5 has a protruding ridge 501 on its end face facing the lower push rod 6, and a positioning post 502 is positioned at the corresponding positioning hole location on the protruding ridge 501. The first groove 301 of the fuse body 3 has several through holes corresponding to the positioning holes. The first groove 301 of the fuse body 3 is located in the second groove of the lower push rod 6. The protruding ridge 501 of the upper push rod 5 is nested into the second groove of the lower push rod 6. The positioning post 502 passes through the through holes of the fuse body 3 and is inserted into the positioning hole, thus clamping and fixing the fuse body 3.

[0028] To further improve arc extinguishing and breaking capabilities, see [link to relevant documentation]. Figure 1 The gap between the upper push rod 5 near the conductor 2 and the outer casing 1 can be filled with gas-generating substance 7, so that the gas-generating substance 7 is close to the fracture point formed after the fuse 3 is broken.

[0029] Alternatively, a gas-generating substance 8 can be directly placed on the outer circumferential surface of the upper push rod 5 near the fuse 3. The gas-generating substance 8 can be placed on the upper push rod 5 through a two-color mold or secondary injection molding. When the fuse 3 is cut, the gas-generating substance on the fuse 3 releases a large amount of gas under the high temperature of the electric arc. One end of the fuse 3, which is held by the fuse breaking assembly, moves with the fuse breaking assembly and eventually attaches to the gap between the upper push rod 5 and the upper shell or to the gas-generating substance on the upper push rod. The electric arc combustion causes the gas-generating substance to release a large amount of gas, reducing the electric arc temperature. At the same time, when the fuse 3 is cut and the broken end moves, the gas-generating substance moves with it and is rubbed and squeezed by the arc extinguishing medium to form many slits. The slits can increase the electric arc voltage, accelerate the rate at which the current drops to zero, and further accelerate the extinction of the electric arc.

Claims

1. An arc-extinguishing structure for activating a fuse, characterized in that, The device includes a housing, and an excitation source, a piston, a conductor, a fuse, an arc-extinguishing medium, and a fuse disconnection assembly disposed within the housing. The piston is disposed corresponding to the conductor and the fuse disconnection assembly. The fuse is connected in parallel to the conductor and has a cutting neck disposed therein. The cutting neck is disposed in the arc-extinguishing medium and the fuse passes through the fuse disconnection assembly. A gas-generating substance is provided at one or both sides of the cutting neck, on the fusible link assembly near the fuse, or at any or a combination of several locations near the contact point between the fusible link assembly and the housing. When the excitation source triggers the action to release high-pressure gas, it drives the piston to move. After the piston disconnects the conductor, it drives the melt disconnecting assembly to move and disconnect the fuse from the cutting neck. The gas-generating substance releases a large amount of gas at high temperature to participate in arc extinguishing.

2. The arc-extinguishing structure for an excitation fuse according to claim 1, characterized in that, The melt cutting assembly includes an upper push rod and a lower push rod nested together, with the melt cutting element passing between the upper push rod and the lower push rod.

3. The arc-extinguishing structure for an excitation fuse according to claim 2, characterized in that, The gap between the upper push rod and the housing is filled with the gas-producing substance.

4. The arc-extinguishing structure for an excitation fuse according to claim 2, characterized in that, The gas-generating substance is provided at the position of the upper push rod near the fuse.

5. The arc-extinguishing structure for an excitation fuse according to claim 4, characterized in that, The gas-generating substance is provided on the outer peripheral surface of the upper push rod near the fuse.

6. The arc-extinguishing structure for an excitation fuse according to claim 5, characterized in that, The gas-producing substance is set on the upper push rod by means of a two-color mold or secondary injection molding.

7. The arc-extinguishing structure for an excitation fuse according to claim 1, characterized in that, The fuse body is provided with multiple rows of parallel cutting slits, and the gas-generating substance is respectively provided on one or both sides of each row of cutting slits.

8. The arc-extinguishing structure for an excitation fuse according to claim 7, characterized in that, The cut-off neck is formed by connecting two variable cross-section structures of different widths, and the gas-producing material is disposed on the variable cross-section structure with the larger width.

9. The arc-extinguishing structure for an excitation fuse according to claim 2, characterized in that, A second recess for nesting is provided on the end of the lower push rod facing the upper push rod. Positioning holes are spaced apart in the second recess. A nesting protrusion is provided on the end of the upper push rod facing the lower push rod. A positioning post is provided on the end face of the protrusion facing the lower push rod, corresponding to the positioning hole. A first recess is provided on the fuse body corresponding to the second recess. A through hole is provided in the first recess, corresponding to the positioning post. The first recess of the fuse body is located in the second recess of the lower push rod. The positioning post of the upper push rod passes through the through hole of the fuse body and is inserted into the positioning hole in the lower push rod, clamping and fixing the fuse body between the upper push rod and the lower push rod.

10. The arc-extinguishing structure for an excitation fuse according to claim 1, characterized in that, The gas-producing substance is an elastic rubber, melamine, or plastic.

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