High-voltage high-current surface-mounted fuse and preparation method thereof

Abstract

The invention provides a high-voltage large-current surface-mounted fuse which comprises a fuse main body, a packaging part and an insulating shell, one side of the insulating shell is recessed inwards to form an accommodating cavity, and the packaging part is used for sealing an opening of the accommodating cavity; the fuse main body comprises two conductive electrodes and a fusing part arranged between the conductive electrodes, the fusing part is located in the accommodating cavity, and the conductive electrodes extend out of the accommodating cavity; the accommodating cavity is also filled with a first filler, and the first filler used for arc extinguishing coats the fusing part; the accommodating cavity is also filled with a second filler, the second filler used for fixing the fuse main body is arranged on the outer side of the fuse main body between the fuse main body and the side wall of the accommodating cavity, and at least part of the second filler is buried in the first filler; the accommodating cavity is also filled with a third filler, and the third filler used for fixing the fuse main body is arranged on the inner side of the fuse main body; the second filler and the third filler coat the two ends of the fusing part to prevent the fusing part from continuously combusting towards the two ends; and at least part of the third filler is buried in the first filler.

Description

Technical Field

[0001] This invention relates to the field of electrical protection components, and in particular to a high-voltage, high-current surface-mount fuse and its manufacturing method. Background Technology

[0002] Surface mount fuses (SMDs) are widely used as circuit protection components in power tools, electric vehicles, and battery packs, and their demand has been increasing in the emerging new energy vehicle industry in recent years. Currently, most SMD fuses on the market have a rated voltage / current below 100VDC@125A and limited breaking capacity, limiting their application to low-voltage systems. However, with the development of new technologies, system voltages and currents in AI computing servers, energy storage, and low-altitude flight applications are gradually increasing, reaching 125VDC@200A and above. For various reasons, current SMD fuses cannot meet the demands of these increasingly high-voltage, high-current applications. When a sudden current surge or instantaneous pulse occurs in the circuit, the fuse fails to provide adequate protection due to insufficient arc-extinguishing capability. Under instantaneous high-energy impacts, the fuse may not only crack or explode but also damage other components in the circuit. Specifically, ceramic-cased fuses have relatively higher rated voltage and current compared to other types. They are generally assembled using a one-piece molded fuse section with a planar design, using silicone rubber or inorganic fillers as arc-extinguishing materials to absorb or extinguish the arc. When silicone rubber is used as the arc-extinguishing material, it directly fills the entire cavity, completely covering the molten material. This type of fuse has relatively poor arc-extinguishing capability. Conversely, when inorganic solid fillers are used, the molten material is filled and covered with solid material, then sealed with a cover plate or silicone sealant. The molten material and the casing are fixed together with a small amount of adhesive. Some fuses have silicone-based arc-damping materials on both sides of the fuse section to prevent further arc combustion. This type of fuse has relatively good arc-extinguishing capability, but its breaking capacity is still limited in high-voltage and high-current applications, and high-energy impacts can still cause side ejection or electrode lifting.

[0003] In order to further improve the rated voltage / current and breaking capacity of surface mount fuses and better meet the future development needs of new technology fields, there is an urgent need to provide a high-voltage, high-current surface mount fuse. Summary of the Invention

[0004] The purpose of this invention is to provide at least one novel high-voltage, high-current surface-mount fuse and its manufacturing method.

[0005] To address the aforementioned problems, a first aspect of the present invention provides a high-voltage, high-current surface-mount fuse, comprising a fuse body, an encapsulation portion, and an insulating shell recessed on one side to form a receiving cavity. The encapsulation portion is used to close the opening of the receiving cavity. The fuse body includes two conductive electrodes and a fusing portion disposed between the conductive electrodes. The fusing portion is located within the receiving cavity, and the conductive electrodes extend out of the receiving cavity. The receiving cavity is further filled with a first filler, which covers the fusing portion for arc extinguishing. The characteristic feature is that the receiving cavity is further filled with a second filler, which is disposed on the outer side of the fuse body between the fuse body and the sidewall of the receiving cavity. At least a portion of the second filler is embedded in the first filler, i.e., located below the top surface of the first filler, to enhance the adhesion between the fuse body and the insulating shell.

[0006] The accommodating cavity is further filled with a third filler, which is used to fix the fuse body and is disposed on the inner side of the fuse body; the second filler and the third filler cover both ends of the fuse portion to prevent the fuse portion from continuing to burn to both ends; and / or, at least part of the third filler is buried in the first filler, that is, located below the top surface of the first filler, to enhance the integration force between the fuse body and the shell and the first filler, as well as the bonding and fixing effect between the fuse body and the insulating shell.

[0007] In one specific embodiment, the composition of the second filler is the same as or different from that of the third filler; and / or, the composition of the encapsulation portion is the same as or different from that of the second filler; and / or, the composition of the encapsulation portion is the same as or different from that of the third filler.

[0008] In one specific embodiment, the first filler is an inorganic solid filler containing quartz sand, and the first filler also contains one or more of melamine, calcium carbonate, magnesium hydroxide, and hollow glass microspheres.

[0009] In one specific embodiment, the second filler, the third filler, and the encapsulation part are colloids, respectively selected from epoxy resin, silicone resin, and acrylic resin.

[0010] In one specific embodiment, the first filler is an inorganic solid filler containing quartz sand, and the first filler also contains one or more of melamine, calcium carbonate, magnesium hydroxide, and hollow glass microspheres.

[0011] In one specific embodiment, the fuse body further includes a connecting section disposed between the fusible portion and the adjacent conductive electrode, the connecting section extending from the opening into the accommodating cavity, the second filler disposed on the outside of the fuse body between the connecting section and the side wall of the accommodating cavity, the third filler disposed on the inside of the connecting section, and the second filler and the third filler covering the connecting sections at both ends of the fusible portion.

[0012] In one specific embodiment, the angle between the connecting segment and the inner wall of the adjacent accommodating cavity is 0-45°; or, the angle between the connecting segment and the inner wall of the adjacent accommodating cavity is 30°.

[0013] In one specific embodiment, the thickness of the conductive electrode is greater than or equal to the thickness of the fused portion; and / or, the thickness of the fused portion is 0.1-1 mm, and the thickness of the conductive electrode is 0.5-2 mm.

[0014] In one specific embodiment, the fuse portion includes two or more fuse groups connected in series, each fuse group containing one or more secondary fuse portions connected in parallel, and each secondary fuse portion having one or more arc shapes.

[0015] The solid first filler works in conjunction with the second and third fillers, and integrates the technical features of two fuse groups with arc-shaped secondary fuse sections connected in series. The high-voltage, high-current surface mount fuses provided can have a rated voltage / current of up to 132V@200A and a breaking capacity of up to 132VDC@5000A. They also have a low current carrying temperature, which can meet the needs of emerging fields such as new energy vehicles, AI computing servers, energy storage, and low-altitude flight for surface mount fuses with high voltage, high current and high breaking capacity.

[0016] In one specific embodiment, when the secondary fuse portion has a single arc shape, the arc shape arches towards the opening of the receiving cavity; and / or, the number of the secondary fuse portions in each fuse group is between 1 and 6. In one specific embodiment, the number of the secondary fuse portions in each fuse group is 4.

[0017] In one specific embodiment, in the left-right direction, two adjacent fuse groups are connected in series by a connecting bridge, and each of the secondary fuse parts of the two adjacent fuse groups is connected to the same connecting bridge.

[0018] In one specific embodiment, the connecting segment, the two adjacent secondary fuse portions in each fuse group, and the connecting bridge are arranged to form a narrow neck, which is circular, rhomboid, or square.

[0019] In one specific embodiment, the secondary fuse extends in the left-right direction, the connecting bridge extends in the front-back direction, one end of the secondary fuse in the left-right direction is connected to the connecting bridge, and the other end of the secondary fuse in the left-right direction is connected to the connecting segment.

[0020] In one specific embodiment, the portion of the connecting part that connects to the secondary fuse part arches downward, and / or the connecting bridge arches downward.

[0021] A second aspect of this invention provides a method for manufacturing a high-voltage, high-current surface-mount fuse, comprising the following steps:

[0022] S1, An insulating shell is prepared using an insulating material, and one side of the insulating shell is recessed inward to form a receiving cavity;

[0023] S2, The fuse body is integrally formed using conductive metal. The fuse body includes two conductive electrodes and a fusing part disposed between the conductive electrodes. The fusing part includes two or more fusing groups connected in series with each other. Each fusing group contains one or more secondary fusing parts connected in parallel with each other. Each secondary fusing part has one or more arc shapes.

[0024] S3, the fuse-breaking portion of the fuse body is placed in the accommodating cavity, and the two conductive electrodes are located outside the accommodating cavity;

[0025] S4, the first filler for extinguishing the arc is filled into the accommodating cavity and covers the fuse portion;

[0026] S5, the opening of the receiving cavity is sealed with the encapsulation part to obtain the high voltage and high current surface mount fuse.

[0027] In a specific embodiment, step S3 specifically includes the following steps:

[0028] S31, the second filler is applied to local areas of the two side walls of the accommodating cavity that are opposite to each other;

[0029] S32, the fuse-breaking portion of the fuse body is placed in the accommodating cavity, the second filler for fixing the fuse body is located on the outside of the fuse body between the fuse body and the side wall of the accommodating cavity, and the two conductive electrodes are located outside the accommodating cavity;

[0030] S33, a third filler is coated on the inside of the fuse body, wherein the composition of the second filler is the same as or different from that of the third filler.

[0031] In one specific embodiment, in step S4, at least a portion of the second filler is embedded within the first filler.

[0032] In one specific embodiment, in step S4, at least a portion of the third packing is embedded within the first packing.

[0033] The beneficial effects of this invention are:

[0034] a. The high-voltage, high-current surface mount fuse provided by the present invention enhances the adhesion between the fuse body and the insulating shell by setting a second filler on the outside of the fuse body;

[0035] b. By covering both ends of the fusible part with the second and third fillers to prevent the fusible part from continuing to burn to both ends, that is, by using the second and third fillers to form an all-round covering of both ends of the fusible part, the arc is extinguished in an auxiliary manner, effectively blocking the continued burning of the electric arc.

[0036] c. At least part of the second and third fillers are embedded in the first filler to enhance the integration force between the fuse body and the shell and the first filler, as well as the bonding and fixing effect between the fuse body and the insulating shell;

[0037] d. By cooperating with each other, the first, second, and third packing materials enhance the arc-extinguishing capability while resisting high-energy impacts, preventing the fuse from cracking and exploding during the arc-extinguishing process, thus improving the rated voltage / current and breaking capacity of the fuse in this invention. Attached Figure Description

[0038] Figure 1 This is a three-dimensional schematic diagram of a high-voltage, high-current surface-mount fuse according to Embodiment 1 of the present invention;

[0039] Figure 2 This is a three-dimensional schematic diagram of the fuse body in Embodiment 1 of the present invention;

[0040] Figure 3 This is a front view of the fuse body in Embodiment 1 of the present invention;

[0041] Figure 4 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention after completing the preparation step S1;

[0042] Figure 5 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention after completing the preparation step S31;

[0043] Figure 6 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention after completing preparation step S32;

[0044] Figure 7 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention after completing preparation step S33;

[0045] Figure 8 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention after completing preparation step S4;

[0046] Figure 9 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 1 of the present invention;

[0047] Figure 10 This is a three-dimensional schematic diagram of the fuse body in Embodiment 2 of the present invention;

[0048] Figure 11 This is a front view of the fuse body in Embodiment 2 of the present invention;

[0049] Figure 12 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 2 of the present invention;

[0050] Figure 13 This is a three-dimensional schematic diagram of a high-voltage, high-current surface-mount fuse according to Embodiment 3 of the present invention;

[0051] Figure 14 This is a three-dimensional schematic diagram of the fuse body in Embodiment 3 of the present invention;

[0052] Figure 15 This is a front view of the fuse body in Embodiment 3 of the present invention;

[0053] Figure 16 This is a cross-sectional view of a high-voltage, high-current surface-mount fuse in Embodiment 3 of the present invention;

[0054] Numbering on the map:

[0055] 1-Encapsulation section; 2-Fuse body; 21-Conductive electrode; 22-Fuse section; 221-Fuse group; 2210-Secondary fuse section; 23-Connecting section; 24-Connecting bridge; 25-Neck; 3-Insulating shell; 31-Accommodation cavity; 4-First filler; 5-Second filler; 6-Third filler. Detailed Implementation

[0056] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0057] The invention can be further understood through the specific embodiments given below, but they are not intended to limit the invention.

[0058] In the description of this invention, the directions such as "front," "rear," "left," "right," "up," "down," "inner," and "outer" are all defined for ease of description, i.e., as... Figure 9As shown in the figure, the left direction is "left", the right direction is "right", the upper direction is "up", the lower direction is "down", the direction perpendicular to the viewpoint is "front" and "back", the direction closer to the connecting bridge is "inner", and the direction farther from the connecting bridge is "outer". The above definition of directions is only for the convenience of describing the present invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0059] Example 1

[0060] like Figure 1-9 As shown, this embodiment provides a high-voltage, high-current surface-mount fuse, including an encapsulation part 1, a fuse body 2, and an insulating shell 3 with one side recessed to form a receiving cavity 31. The encapsulation part 1 is used to close the opening of the receiving cavity 31. The fuse body 2 includes two conductive electrodes 21 and a fusing part 22 disposed between the conductive electrodes 21. The fusing part 22 is located inside the receiving cavity 31, and the conductive electrodes 21 extend out of the receiving cavity 31. The fusing part 22 includes two fusing groups 221 connected in series. In this embodiment, the two fusing groups 221 are fixed and electrically connected by a connecting bridge 24. In other embodiments, the number of fusing groups 221 can be set to two or more. In this embodiment, the connecting bridge 24 is also part of the fuse body 22. Each fuse group 221 contains one or more secondary fuse parts 2210 connected in parallel. Each secondary fuse part 2210 has a single arc shape and is connected to a connecting bridge 24. Specifically, two fuse groups 221 are connected in series through the connecting bridge 24, and each secondary fuse part 2210 of the two fuse groups 221 is connected to the connecting bridge 24. In other embodiments, each secondary fuse part 2210 may be configured to have multiple arc shapes, in which case each secondary fuse part 2210 presents a wavy configuration. In other embodiments, there may be two or more fuse groups 221. In the left-right direction, two adjacent fuse groups 221 are connected in series through the connecting bridge 24, and each secondary fuse part 2210 of the two adjacent fuse groups 221 is connected to the same connecting bridge 24.

[0061] In one specific embodiment, the number of fuse groups 221 connected in series can be two or more. In this embodiment, the fuse body 2 is made of copper or copper alloy and tin-plated. In some embodiments, the fuse body 2 is integrally stamped. The fuse body 2 also includes a connecting segment 23 disposed between the fuse portion 22 and the adjacent conductive electrode 21. The two connecting segments 23 extend from the opening of the receiving cavity 31 into the receiving cavity 31, and the angle between the generally planar connecting segment 23 and the inner wall of the adjacent receiving cavity 31 is 0-45°. In this embodiment, the angle between the connecting segment 23 and the inner wall of the adjacent receiving cavity 31 is 30°. In this embodiment, the integrally formed fuse body 2 has the same thickness, ranging from 0.1-2 mm.

[0062] The orientation of the arc is not limited. In this embodiment, the arc in each secondary fuse section 2210 is set as a single arched opening facing the receiving cavity 31, which facilitates the installation of the fuse body and makes full use of the space of the receiving cavity 31. In addition, the number of secondary fuse sections 2210 in each fuse group 221 is not limited, preferably between 1 and 6. In this embodiment, the number of secondary fuse sections 2210 in each fuse group 221 is 4. The arrangement of multiple secondary fuse sections 2210 can fully divide the voltage and current after energization. The connecting section 23, two adjacent secondary fuse sections 2210 in each fuse group 221, and the connecting bridge 24 form a narrow neck 25. The narrow neck 25 can be a round hole, a diamond hole, or a square hole, etc., to provide products with different fusing characteristics. Specifically, the secondary fuse section 2210 extends in the left-right direction, the connecting bridge 24 extends in the front-back direction, one end of the secondary fuse section 2210 in the left-right direction is connected to the connecting bridge 24, and the other end of the secondary fuse section 2210 in the left-right direction is connected to the connecting section 23. The part of the connecting section 23 connected to the secondary fuse section 2210 arches downward, the connecting bridge 24 arches downward, and the fuse body 2 has three downward arched parts and two upward arched parts in the left-right direction.

[0063] The accommodating cavity 31 is also filled with a first filler 4, which is used for arc extinguishing and covers the fusible portion 22. In some embodiments, the first filler 4 is an inorganic solid filler that is filled into the accommodating cavity 31 in a bulk stacked form, which can fully absorb and extinguish the electric arc. Specifically, the first filler 4 contains quartz sand with different particle sizes of 60-120 mesh. In this embodiment, quartz sand is the main component of the first filler 4. In addition, the first filler 4 also contains one or more powders with flame-retardant or arc-extinguishing capabilities, such as melamine, calcium carbonate, magnesium hydroxide, and hollow glass microspheres. The first filler 4 fills from the bottom of the accommodating cavity 31 to the middle fusible portion 22 and completely covers the fusible portion 22.

[0064] The cavity 31 is also filled with a second filler 5. The second filler 5 for fixing the fuse body 2 is located on the outside of the fuse body 2 between the fuse body 2 and the side wall of the cavity 31. At least part of the second filler 5 is buried in the first filler 4, that is, located below the top surface of the first filler 4, so as to enhance the adhesion between the fuse body 2 and the insulating shell 3.

[0065] In one specific embodiment, the accommodating cavity 31 is further filled with a third filler 6, which is used to fix the fuse body 2 and is disposed inside the fuse body 2; the second filler 5 and the third filler 6 cover the connecting sections 23 at both ends of the fuse section 22 to prevent the fuse section 22 from continuing to burn at both ends. In some embodiments, at least part of the third filler 6 is embedded in the first filler 4.

[0066] In one specific embodiment, the composition of the second filler 5 may be the same as or different from that of the third filler 6; and / or, the composition of the encapsulation part 1 may be the same as or different from that of the second filler 5; and / or, the composition of the encapsulation part 1 may be the same as or different from that of the third filler 6. In this embodiment, the second filler 5, the third filler 6, and the encapsulation part 1 are all colloids with the same composition. The encapsulation part 1 fills the space in the accommodating cavity 31 except for the first filler 4, the second filler 5, the third filler 6, and the fuse body 2. After curing, it achieves the encapsulation and fixation of the high-voltage, high-current surface mount fuse. The second filler 5 and the third filler 6 are selected from any heat-resistant and weather-resistant organic adhesives with strong adhesion, such as high temperature resistance and flame retardancy. Specifically, in this embodiment, the second filler 5, the third filler 6, and the encapsulation part 1 are selected from one of epoxy resin, silicone resin, and acrylic resin.

[0067] The method for manufacturing a high-voltage, high-current surface-mount fuse of the present invention includes the following steps:

[0068] S1, an insulating shell 3 is made of insulating material, and one side of the insulating shell 3 is recessed inward to form a receiving cavity 31; the insulating material is ceramic, epoxy resin or other flame-retardant reinforcing material.

[0069] S2, the fuse body 2 is integrally formed from a conductive metal made of copper or copper alloy. The fuse body 2 includes two conductive electrodes 21 and a fusing part 22 disposed between the conductive electrodes 21. The fusing part 22 includes two or more fusing groups 221 connected in series with each other. Each fusing group 221 contains one or more secondary fusing parts 2210 connected in parallel with each other. Each secondary fusing part 2210 has one or more arcs. The fuse body 2 is processed according to the design pattern by wet etching, laser cutting or mechanical stamping, etc.

[0070] S3, the fuse-breaking portion 22 of the fuse body 2 is placed in the receiving cavity 31, and the two conductive electrodes 21 are located outside the receiving cavity 31; in this embodiment, step S3 specifically includes the following steps:

[0071] S31, the second filler 5 is applied to the local areas of the two opposite side walls of the accommodating cavity 31 by dispensing. The second filler 5 is selected from high temperature resistant, flame retardant, strong adhesive, and any heat-resistant and weather-resistant organic adhesive, which is used to bond and fix the fuse body 2 to the insulating shell 3.

[0072] S32, the fuse-breaking part 22 of the fuse body 2 is placed in the accommodating cavity 31, the second filler 5 for fixing the fuse body 2 is located on the outside of the fuse body 2 between the fuse body 2 and the side wall of the accommodating cavity 31, the fuse body 2 and the insulating shell 3 are bonded and fixed by the second filler 5, and the two conductive electrodes 21 are located outside the accommodating cavity 31.

[0073] S33, the third filler 6 is coated on the inner side of the fuse body 2, so that the fuse body 2 at both ends of the fusible part 22 is completely covered by the second filler 5 and the third filler 6. The second filler 5 and the third filler 6 can not only assist in arc extinguishing, but also prevent the fusible part 22 from continuing to burn at both ends, and at the same time play a role in bonding and fixing the fuse body 2. The composition of the second filler 5 may be the same as or different from that of the third filler 6.

[0074] S4, the first filler 4 for extinguishing the arc is filled into the receiving cavity 31 from the bottom and covers the fuse portion 22; in some embodiments, at least a portion of the second filler 5 is buried in the first filler 4; in some embodiments, at least a portion of the third filler 6 is buried in the first filler 4; in this embodiment, at least a portion of the second filler 5 and at least a portion of the third filler 6 are buried in the first filler 4.

[0075] S5, the opening of the receiving cavity 31 is sealed with the encapsulation part 1 to obtain a high-voltage, high-current surface-mount fuse. In this embodiment, the material composition of the encapsulation part 1 may be the same as or different from that of the arc-extinguishing fillers 2 and 3. It mainly fills the area from the upper part of the first filler 4 to the opening of the receiving cavity 31, and is mainly used to seal the entire receiving cavity 31. The encapsulation part 1 is subjected to natural leveling and curing treatment.

[0076] Compared with the prior art, the high-voltage, high-current surface-mount fuse provided in this embodiment, by setting two fuse groups 221 containing arc-shaped secondary fuse parts 2210 connected in series, compared with the traditional single-bend or flat solution, when the secondary fuse part 2210 melts, the arc can be more dispersed in the first filler 4 used for arc extinguishing, while reducing the metal vapor / particle concentration in the same area, resulting in a larger resistance after the break, and thus being more fully absorbed by the first filler 4 to achieve rapid arc extinguishing. Meanwhile, the first filler 4, which is an inorganic solid filler, has a strong arc-extinguishing ability, while the second filler 5 and the third filler 6, which are high-temperature resistant, flame-retardant, and have strong adhesive properties, completely cover both ends of the fuse part 22 and achieve the bonding of the fuse body to the insulating shell 3. At the same time, the design of embedding at least part of the second filler 5 and the third filler 6 within the first filler 4 provides a high-voltage, high-current surface mount fuse with a rated voltage / current that can be significantly increased to 132V@200A, and a breaking capacity that can be increased to 132VDC@5000A and 150VDC@3000A. Moreover, the current-carrying temperature is low, which can meet the needs of emerging fields such as new energy vehicles, AI computing servers, energy storage, and low-altitude flight for surface mount fuses with high voltage, high current, and high breaking capacity.

[0077] Example 2

[0078] like Figure 10-12 As shown, compared to Embodiment 1, in this embodiment, the thickness of the conductive electrode 21 is set to be greater than the thickness of the fusible link 22, which enhances the heat dissipation capacity of the conductive electrode 21 and reduces the resistance of the fuse by approximately 15-20%. The thickness of the fusible link 22 is 0.1-1 mm, and the thickness of the conductive electrode 21 is 0.5-2 mm. Simultaneously, the inorganic solid filler of the first filler 4 is filled into the accommodating cavity 31 in a gel-cured form. Compared to a bulk stacking method, combined with the thickened conductive electrode 21, this effectively increases the heat dissipation capacity of the fuse, providing better breaking capacity and making it suitable for applications with a rated current of 200A and above.

[0079] Example 3

[0080] like Figure 13-16 As shown, compared to Embodiment 2, the difference in this embodiment is that the angle between the connecting segment 23 and the inner wall of the adjacent accommodating cavity 31 is 0°. At this time, the connecting segment 23 is parallel to and almost adjacent to the inner wall of the accommodating cavity 31, which enhances the adhesion between the fuse body 2 and the insulating shell 3.

[0081] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A high-voltage, high-current surface-mount fuse, characterized in that: The device includes a fuse body, an encapsulation portion, and an insulating outer shell that is recessed inward on one side to form a receiving cavity. The encapsulation portion is used to close the opening of the receiving cavity. The fuse body includes two conductive electrodes and a fusible portion disposed between the conductive electrodes. The fusible portion is located within the receiving cavity, and the conductive electrodes extend out of the receiving cavity. The receiving cavity is also filled with a first filler for extinguishing arcs, which covers the fusible portion. The receiving cavity is also filled with a second filler for fixing the fuse body. The second filler is disposed on the outer side of the fuse body between the fuse body and the sidewall of the receiving cavity, and at least a portion of the second filler is embedded in the first filler. The receiving cavity is also filled with a third filler for fixing the fuse body, which is disposed on the inner side of the fuse body. The second filler and the third filler cover both ends of the fusible portion to prevent the fusible portion from continuing to burn towards both ends. At least a portion of the third filler is embedded in the first filler.

2. The high-voltage, high-current surface-mount fuse according to claim 1, characterized in that: The composition of the second filler is the same as or different from that of the third filler; and / or, the composition of the encapsulation part is the same as or different from that of the second filler; and / or, the composition of the encapsulation part is the same as or different from that of the third filler.

3. The high-voltage, high-current surface-mount fuse according to claim 2, characterized in that: The second filler, the third filler, and the encapsulation part are selected from one of epoxy resin, silicone resin, and acrylic resin.

4. The high-voltage, high-current surface-mount fuse according to claim 1, characterized in that: The first filler comprises quartz sand, and the first filler also comprises one or more of melamine, calcium carbonate, magnesium hydroxide, and hollow glass microspheres.

5. The high-voltage, high-current surface-mount fuse according to claim 1, characterized in that: The fuse body further includes a connecting section disposed between the fuse section and the adjacent conductive electrode. The connecting section extends from the opening into the accommodating cavity. The second filler is disposed on the outside of the fuse body between the connecting section and the side wall of the accommodating cavity. The third filler is disposed on the inside of the connecting section. The second filler and the third filler cover the connecting sections at both ends of the fuse section.

6. The high-voltage, high-current surface-mount fuse according to claim 5, characterized in that: The angle between the connecting segment and the inner wall of the adjacent accommodating cavity is 0-45°; or, the angle between the connecting segment and the inner wall of the adjacent accommodating cavity is 30°.

7. The high-voltage, high-current surface-mount fuse according to claim 1, characterized in that: The thickness of the conductive electrode is greater than or equal to the thickness of the fused portion; and / or, the thickness of the fused portion is 0.1-1 mm, and the thickness of the conductive electrode is 0.5-2 mm.

8. The high-voltage, high-current surface-mount fuse according to any one of claims 1-7, characterized in that: The fuse section includes two or more fuse groups connected in series, each fuse group contains one or more secondary fuse sections connected in parallel, and each secondary fuse section has one or more arc shapes.

9. The high-voltage, high-current surface-mount fuse according to claim 8, characterized in that: When the secondary fuse portion has a single arc shape, the arc shape arches toward the opening of the receiving cavity; and / or, the number of the secondary fuse portions in each fuse group is between 1 and 6.

10. A method for manufacturing a high-voltage, high-current surface-mount fuse according to any one of claims 1-9, characterized in that: Includes the following steps: S1, An insulating shell is prepared using an insulating material, and one side of the insulating shell is recessed inward to form a receiving cavity; S2, The fuse body is integrally formed using conductive metal. The fuse body includes two conductive electrodes and a fusing part disposed between the conductive electrodes. The fusing part includes two or more fusing groups connected in series with each other. Each fusing group contains one or more secondary fusing parts connected in parallel with each other. Each secondary fusing part has one or more arc shapes. S3, the fuse-breaking portion of the fuse body is placed in the accommodating cavity, and the two conductive electrodes are located outside the accommodating cavity; S4, the first filler for extinguishing the arc is filled into the accommodating cavity and covers the fuse portion; S5, the opening of the receiving cavity is sealed with the encapsulation part to obtain the high voltage and high current surface mount fuse.

11. The method for manufacturing a high-voltage, high-current surface-mount fuse according to claim 10, characterized in that: Step S3 specifically includes the following steps: S31, the second filler is applied to local areas of the two side walls of the accommodating cavity that are opposite to each other; S32, the fuse-breaking portion of the fuse body is placed in the accommodating cavity, the second filler for fixing the fuse body is located on the outside of the fuse body between the fuse body and the side wall of the accommodating cavity, and the two conductive electrodes are located outside the accommodating cavity; S33, a third filler is coated on the inside of the fuse body, wherein the composition of the second filler is the same as or different from that of the third filler.

12. The method for manufacturing a high-voltage, high-current surface-mount fuse according to claim 11, characterized in that: In step S4, at least a portion of the second packing is embedded within the first packing.

13. The method for manufacturing a high-voltage, high-current surface-mount fuse according to claim 12, characterized in that: In step S4, at least a portion of the third packing is embedded within the first packing.

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