A fusible element structure for a full-range protection fuse

Abstract

This utility model relates to the fuse element structure, specifically to a fuse element structure for a full-range protection fuse; it includes a fuse element, and a first fusing part and multiple second fusing parts arranged along the length of the fuse element; when a small overload current passes through the fuse element, the first fusing part melts before the second fusing parts. The advantages of this utility model are: after installing the fuse with the full-range protection fuse element structure in a circuit, when a small overload current passes through the circuit, the melting point of the first fusing part is lower than the melting points of the fuse element and the second fusing parts, and its resistivity is higher than that of the fuse element and the second fusing parts. Therefore, the first fusing part will melt first, protecting the circuit and contributing to effective protection against currents across the entire range.

Description

Technical Field

[0001] This utility model relates to the fuse element structure, specifically to a fuse element structure for a full-range protection fuse. Background Technology

[0002] A fuse, commonly known as a "fuse," is an overcurrent protection device widely used in power distribution and control systems, primarily for short-circuit or overload protection. Currently, the mainstream thermal fuse on the market consists of an insulating tube, terminals, a cover plate, a fusible element, and an arc-extinguishing medium, among other auxiliary materials. Under specified voltage conditions, when the line current flows through the fusible element, the current-sensing point (at the narrowest point) of the fusible element melts and breaks the circuit within a specified time, thus safely interrupting the fault current.

[0003] While existing full-range protection fuses can perform the breaking task to some extent when interrupting large breaking currents, their design often compromises on protection against small overload currents (fault currents less than 10 times the rated operating current) to achieve this function. When faced with small overload currents, they cannot guarantee that the fuse will disconnect at the most suitable location, which can easily lead to untimely or abnormal breaking, making it difficult to achieve efficient and reliable full-range protection under different current conditions. Utility Model Content

[0004] The purpose of this invention is to solve the technical problem that existing fuses cannot ensure that they disconnect at the most suitable position when faced with overload and small current, and are prone to untimely or abnormal disconnection. This invention provides a fuse element structure for a full-range protection fuse.

[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0006] A fusible element structure for a full-range protection fuse includes a fusible element, a first fusible part and a plurality of second fusible parts disposed along the length of the fusible element;

[0007] When the molten material is subjected to an overloaded small current, the first fusible part melts before the second fusible part.

[0008] Furthermore, the melting point of the first fusible portion is lower than that of the melt and the second fusible portion, and its resistivity is greater than that of the melt and the second fusible portion.

[0009] Furthermore, both the first and second fuse portions are provided with multiple through holes evenly distributed along the width direction of the melt.

[0010] The first or second fusible section between two adjacent through holes forms a narrow diameter.

[0011] Furthermore, the material of the melt and the second fused portion is any one of copper, silver, or a copper-silver alloy.

[0012] Furthermore, the first fusible link is made of a gold-silicon alloy.

[0013] Furthermore, the first fused portion is located in the middle of the melt.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] 1. The fuse structure of the full-range protection fuse provided by this utility model has a first fusing part and multiple second fusing parts arranged along the length of the fuse body. The melting point of the first fusing part is lower than that of the fuse body and the second fusing parts, and the resistivity is higher than that of the fuse body and the second fusing parts. After the fuse with the fuse structure of the full-range protection fuse is installed in the circuit, when an overload small current passes through the circuit, the first fusing part will melt first to protect the circuit, which helps to achieve effective protection of the full range of current.

[0016] 2. The fusible element structure of the full-range protection fuse provided by this utility model has a first fusing part made of gold-silicon alloy and a second fusing part and fusible element made of silver. The melting point of the gold-silicon alloy is 360℃, and the melting point of silver is 961.8℃. The melting point of the gold-silicon alloy is lower than that of silver, and the resistivity of the gold-silicon alloy is greater than that of silver. Due to the good electrical conductivity and high thermal conductivity of silver, it can quickly conduct current and heat. When the fuse is connected to the circuit, during normal operation, the current passes through the composite structure of silver and gold-silicon alloy. Due to the low resistance of silver, less heat is generated. However, when a small overload current passes through, the gold-silicon alloy will generate more heat due to its own resistance characteristics. Moreover, its melting point is low, and the gold-silicon alloy melts first when the temperature reaches 360℃, thereby achieving precise disconnection under small overload current conditions and protecting the circuit.

[0017] 3. The fusible element structure of the full-range protection fuse provided by this utility model, when interrupting a large breaking current, causes the heat generated by the instantaneous increase in current to rapidly diffuse throughout the fusible element. At this time, each row of narrow diameters becomes a region of concentrated current density. According to the principle of heat accumulation, heat will rapidly accumulate at the narrow diameters. Due to the good electrical and thermal conductivity of silver, heat can be quickly transferred to the narrow diameters, allowing the fusible element to normally break at each row of narrow diameters. This avoids the abnormal breaking that may occur in gold-silicon alloys under large current due to excessive current thermal shock, ensuring the stability and reliability of the fuse breaking under large breaking current, and achieving effective protection of the full range of currents. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model. Figure 1 ;

[0019] Figure 2 This is a schematic diagram of the structure of an embodiment of the present utility model. Figure 2 .

[0020] Explanation of reference numerals in the attached drawings: 1-melt, 2-first fused section, 3-second fused section, 4-through hole, 5-narrow diameter. Detailed Implementation

[0021] The technical solutions of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] like Figure 1 and Figure 2 As shown, a fusible element structure for a full-range protection fuse is applied to a gPV type fuse; it includes a fusible element 1, and a first fusing part 2 and a plurality of second fusing parts 3 arranged along the length direction of the fusible element 1; the first fusing part 2 is located in the middle of the fusible element 1, and the material of the first fusing part 2 is a gold-silicon alloy; the material of the fusible element 1 and the second fusing parts 3 is silver.

[0023] The melting point of the gold-silicon alloy is 360℃, and the melting point of silver is 961.8℃; that is, the melting point of the first fusing part 2, which is made of gold-silicon alloy, is lower than the melting point of the melt 1 and the second fusing part 3, and its resistivity is greater than that of the melt 1 and the second fusing part 3.

[0024] In order to make the first fuse part 2 and the second fuse part 3 easier to fuse when passing overload small current, the first fuse part 2 and the second fuse part 3 are provided with a plurality of through holes 4 evenly distributed along the width direction of the melt 1, and the first fuse part 2 or the second fuse part 3 between two adjacent through holes 4 forms a narrow diameter 5.

[0025] After the fuse is connected to the circuit, when a small overload current (a fault current less than 10 times the rated operating current) passes through the circuit, the first fuse part 2, which is made of gold-silicon alloy, will generate more heat due to its own resistance characteristics. Moreover, its melting point is low. When the temperature at the first fuse part 2 reaches 360°C, it will melt first, thereby achieving precise disconnection under small overload current conditions and protecting the circuit.

[0026] When a large breaking current passes through the circuit, the heat generated by the instantaneous increase in current rapidly diffuses throughout the entire fuse 1. At this time, each row of narrow diameters 5 becomes a region of concentrated current density. According to the principle of heat accumulation, heat will rapidly accumulate at the narrow diameters 5. Due to the good electrical and thermal conductivity of silver, heat can be quickly transferred to the narrow diameters 5, allowing the fuse 1 to normally break at each row of narrow diameters 5. This avoids the abnormal breaking that may occur in the gold-silicon alloy under large current due to excessive current thermal shock, ensuring the stability and reliability of the fuse breaking under large breaking current, and achieving effective protection of the entire range of currents.

[0027] In other embodiments of this utility model, the melt 1 and the second fusible part 3 are made of copper or a copper-silver alloy.

[0028] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any changes or substitutions within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A fusible link structure for a full-range protection fuse, characterized by: It includes a melt (1), and a first fusing part (2) and a plurality of second fusing parts (3) arranged along the length direction of the melt (1); When the melt (1) is subjected to an overloaded small current, the first fuse (2) melts before the second fuse (3).

2. The fuse structure of a full-range protection fuse according to claim 1, characterized in that: The melting point of the first fused section (2) is lower than that of the melt (1) and the second fused section (3), and its resistivity is greater than that of the melt (1) and the second fused section (3).

3. The fusible element structure of the full-range protection fuse according to claim 1, characterized in that: The first fuse section (2) and the second fuse section (3) are each provided with a plurality of through holes (4) evenly distributed along the width direction of the melt (1); A narrow diameter (5) is formed between two adjacent through holes (4) by a first fusible portion (2) or a second fusible portion (3).

4. The fusible element structure of the full-range protection fuse according to claim 1, characterized in that: The melt (1) and the second fused part (3) are made of copper, silver or copper-silver alloy.

5. The fusible element structure of the full-range protection fuse according to any one of claims 1-3, characterized in that: The first fusible part (2) is made of gold-silicon alloy.

6. The fusible element structure of the full-range protection fuse according to claim 5, characterized in that: The first fused section (2) is located in the middle of the melt (1).

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