Temperature fuse

Abstract

The utility model discloses a temperature fuse, which comprises a shell and a low-melting-point alloy wire, an accommodating cavity is formed in the shell, the low-melting-point alloy wire is arranged in the accommodating cavity, and a fusing aid is arranged in the accommodating cavity and is arranged on the outer side of the low-melting-point alloy wire; a first wire and a second wire are further included, a first bare wire end is formed on the first wire, a second bare wire end is formed on the second wire, the first bare wire end and the second bare wire end are conductively connected to the left end and the right end of the low-melting-point alloy wire respectively, an installation cavity is formed in the shell, the upper end of the installation cavity is communicated with the containing cavity, and the lower end of the installation cavity penetrates through the shell. A breathable ceramic block is arranged in the mounting cavity, the upper end of the breathable ceramic block is connected to the lower side of the fusing aid, a pouring sealant part is arranged in the mounting cavity, the pouring sealant part is arranged on the lower side of the fusing aid, the breathable ceramic block penetrates through the pouring sealant part, and the first wire and the second wire penetrate through the pouring sealant part. The reliability of the thermal fuse is improved.

Description

Technical Field

[0001] This utility model relates to the field of fuses, specifically to a temperature fuse. Background Technology

[0002] Currently, thermal fuses consist of a low-melting-point alloy wire and a housing. The low-melting-point alloy wire is housed within the housing, which is made of ceramic. Leads are connected to both ends of the low-melting-point alloy wire, extending beyond the housing. To ensure a good fracture surface when the low-melting-point alloy wire melts, it is placed within a fluxing agent. This means that when the low-melting-point alloy wire melts, the fluxing agent has already melted due to the high temperature. The main component of the fluxing agent is rosin. Examples can be found in Chinese Utility Model Patent Publication No. CN211605039U, "An Alloy-Type Thermal Fuse," and Chinese Utility Model Patent Publication No. CN202307688U, "An Alloy-Type Thermal Fuse with High Ampere Capacity." Some thermal fuses have relatively high melting temperatures, such as around 200°C. However, the melting temperature of the flux is significantly lower. The flux may melt within the operating range of the low-melting-point alloy wire, meaning it may melt even before reaching the wire's melting temperature. Once the high temperature is relieved, the flux cools and solidifies, and the fuse can resume normal operation. However, because the flux releases gas when it melts, a large amount of gas, if sealed within the casing by potting compound, can cause the casing to rupture due to excessive internal pressure or damage the potting compound, leading to significant flux leakage. This affects the fuse's normal melting function, indicating insufficient reliability. Therefore, improvements to existing thermal fuses are necessary. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a temperature fuse with high reliability.

[0004] The objective of this utility model is achieved through the following technical solution.

[0005] The temperature fuse disclosed in this utility model includes a housing and a low-melting-point alloy wire. A receiving cavity is formed within the housing, and the low-melting-point alloy wire is disposed within the receiving cavity. A fluxing agent is disposed within the receiving cavity and located on the outside of the low-melting-point alloy wire. The fuse also includes a first conductor and a second conductor. The first conductor has a first bare wire end, and the second conductor has a second bare wire end. The first and second bare wire ends are electrically connected to the left and right ends of the low-melting-point alloy wire, respectively. An mounting cavity is formed within the housing, with its upper end connected to the receiving cavity and its lower end penetrating the housing. A breathable ceramic block is disposed within the mounting cavity, with its upper end connected to the lower side of the fluxing agent. A potting compound portion is disposed within the mounting cavity, located on the lower side of the fluxing agent. The breathable ceramic block passes through the potting compound portion, and the first and second conductors pass through the potting compound portion.

[0006] Preferably, the breathable ceramic block has a cover and an air outlet column. The upper end of the air outlet column is integrally connected to the lower side of the cover. The fluxing agent and the potting compound are separated by the cover. The air outlet column passes through the potting compound, and the first bare wire end and the second bare wire end pass through the cover.

[0007] Preferably, a stepped portion is formed between the accommodating cavity and the mounting cavity, and the left and right ends of the cover are respectively attached to the lower side of the corresponding stepped portion.

[0008] Preferably, the first conductor has a first insulating sheath, the second conductor has a second insulating sheath, the end of the first insulating sheath corresponding to the first bare wire end is disposed in the potting compound portion, and the end of the second insulating sheath corresponding to the second bare wire end is disposed in the potting compound portion.

[0009] Preferably, the upper part of the outer casing has mounting holes.

[0010] Compared with the prior art, the advantages of this utility model are as follows: by setting an installation cavity inside the outer shell, the upper end of the installation cavity is connected to the receiving cavity, the lower end of the installation cavity penetrates the outer shell, a ventilated ceramic block is provided inside the installation cavity, the upper end of the ventilated ceramic block is connected to the lower side of the flux, a potting compound is provided inside the installation cavity, the potting compound is located on the lower side of the flux, the ventilated ceramic block passes through the potting compound, and the first wire and the second wire pass through the potting compound, so that the gas in the receiving cavity can be discharged through the ventilated ceramic block, thereby improving the reliability of the thermal fuse. Attached Figure Description

[0011] Figure 1 This is a front view schematic diagram of the thermal fuse of this utility model.

[0012] Figure 2 This is a schematic diagram of the outer shell of this utility model.

[0013] Figure 3 This is a partial structural diagram of the temperature fuse of this utility model from the left side.

[0014] Figure 4 This is a bottom view of the structure of the breathable ceramic block of this utility model.

[0015] Figure 5 This is a schematic diagram of the connection structure between the low-melting-point alloy wire of this utility model and the first bare wire end and the second bare wire end.

[0016] Labeling: 1. Outer shell; 11. Mounting hole; 101. Mounting cavity; 102. Stepped portion; 1011. Low melting point alloy wire; 2. First conductor; 3. First bare wire end; 31. First insulating sheath; 32. Second conductor; 4. Second bare wire end; 41. Second insulating sheath; 42. Breathable ceramic block; 5. Cover; 51. Air outlet column; 52. Through hole; 501. Flux for melting and severing; 6. Encapsulating adhesive portion; 7. Detailed Implementation

[0017] The present invention will now be further described with reference to the accompanying drawings.

[0018] The temperature fuse of this utility model, such as Figures 1 to 3 As shown, the device includes a housing 1 and a low-melting-point alloy wire 2. The housing 1 can be made of ceramic. A receiving cavity 101 is formed inside the housing 1. The low-melting-point alloy wire 2 is disposed within the receiving cavity 101. A fluxing agent 6 is disposed within the receiving cavity 101, and the fluxing agent 6 is located on the outside of the low-melting-point alloy wire 2; that is, the fluxing agent 6 encapsulates the low-melting-point alloy wire 2. Figures 1 to 3 As shown, the temperature fuse of this utility model also includes a first conductor 3 and a second conductor 4. The first conductor 3 has a first bare wire end 31, and the second conductor 4 has a second bare wire end 41. The first bare wire end 31 and the second bare wire end 41 are electrically connected to the left and right ends of the low melting point alloy wire 2, respectively. In other words, the first bare wire end 31 is exposed by stripping one end of the first insulating outer sheath 32 from the first conductor 3. Figure 5 As shown, the first bare wire end 31 and the second bare wire end 41 can be welded to the low-melting-point alloy wire 2. For example... Figure 2 As shown, a mounting cavity 102 is formed inside the outer casing 1. The upper end of the mounting cavity 102 communicates with the receiving cavity 101, and the lower end of the mounting cavity 102 penetrates the outer casing 1. In other words, the mounting cavity 102 is configured to open downwards. Figure 1 and Figure 3As shown, a breathable ceramic block 5 is provided in the mounting cavity 102. The upper end of the breathable ceramic block 5 is connected to the lower side of the flux 6. A potting compound 7 is provided in the mounting cavity 102. The potting compound 7 is located on the lower side of the flux 6. That is to say, the potting compound 7 seals the flux 6 and the low melting point alloy wire 2 in the accommodating cavity 101. The breathable ceramic block 5 passes through the potting compound 7. The first wire 3 and the second wire 4 pass through the potting compound 7. Thus, the lower opening of the mounting cavity 102 is sealed by the potting compound 7 around the entire circumference. The potting compound 7 also seals and abuts against the first wire 3 and the second wire 4 around the entire circumference. The potting compound 7 abuts against the breathable ceramic block 5 around the entire circumference. Because the potting compound 7 adheres to the inner wall of the mounting cavity 102, the potting compound 7 adheres to the first wire 3 and the second wire 4, thereby preventing the first wire 3 and the second wire 4 from shifting relative to the outer shell 1, and the potting compound 7 adheres to the breathable ceramic block 5 to fix the breathable ceramic block 5.

[0019] The potting compound 7 can be made of high-temperature resistant epoxy resin. For example, refer to Chinese Invention Patent Publication No. CN118772589B, "Preparation and Application of a High-Temperature Resistant Epoxy Resin". The breathable ceramic block 5 has a porous structure. For example, refer to Chinese Invention Patent Publication No. CN118724571B, "Preparation Method of Porous Ceramics and Porous Ceramics", and Chinese Invention Patent Publication No. CN110935237B, "Multi-level Porous Silicon Carbide Porous Ceramics for High-Temperature Flue Gas Filtration and Preparation Method Thereof".

[0020] like Figure 1 As shown, when the flux 6 melts under high temperature, it releases gas, causing an increase in pressure within the accommodating cavity 101. Since the upper end of the permeable ceramic block 5 is connected to the lower side of the flux 6 and passes through the potting compound 7, the gas within the accommodating cavity 101 can be discharged through the permeable ceramic block 5 to the lower side of the potting compound 7. In other words, the gas can pass through the potting compound 7 along the permeable ceramic block 5 and finally exit through the lower opening of the mounting cavity 102, thereby reducing the pressure within the accommodating cavity 101 and preventing gas buildup inside the accommodating cavity 101. Excessive pressure can cause the outer casing 1 to crack or the potting compound 7 to be damaged. However, because the permeable structure of the permeable ceramic block 5 is a fine and tortuous channel structure, and because the viscosity of the liquid flux 6 is relatively high, the liquid flux 6 does not easily penetrate or pass through the permeable ceramic block 5. Therefore, when the high temperature is relieved, the flux 6 cools down and returns to a solid state. The flux 6 can still wrap around the low melting point alloy wire 2, thereby restoring the thermal fuse to normal function. Thus, the thermal fuse of this invention has higher reliability (compared to the prior art).

[0021] Furthermore, such as Figure 1 and Figure 3As shown, the breathable ceramic block 5 has a cover 51 and an exhaust column 52. The upper end of the exhaust column 52 is integrally connected to the lower side of the cover 51. The fluxing agent 6 and the potting compound 7 are separated by the cover 51, that is, the fluxing agent 6 is located on the upper side of the cover 51, and the potting compound 7 is located on the lower side of the cover 51. The exhaust column 52 passes through the potting compound 7, that is, the gas in the accommodating cavity 101 can be discharged to the outside of the outer casing 1 through the exhaust column 52. The first bare wire end 31 and the second bare wire end 41 pass through the cover 51, as shown. Figure 4 As shown, a through hole 501 is formed on the cover portion 51, and the first bare wire end 31 and the second bare wire end 41 are respectively adapted to pass through the corresponding through hole 501. Since the potting compound portion 7 is also heated in a high-temperature environment, if the potting compound portion 7 and the flux 6 are in contact at high temperature for a long time, the potting compound portion 7 and the flux 6 may react unexpectedly and affect the performance of the flux 6. However, since the flux 6 and the potting compound portion 7 are separated by the cover portion 51 in this embodiment, the contact between the potting compound portion 7 and the flux 6 can be avoided.

[0022] Furthermore, such as Figure 2 As shown, a stepped portion 1011 is formed between the receiving cavity 101 and the mounting cavity 102, such as... Figure 1 As shown, the left and right ends of the cover 51 are respectively attached to the lower side of the corresponding step 1011, so that the step 1011 can position the breathable ceramic block 5.

[0023] Furthermore, such as Figure 1 As shown, the first conductor 3 is provided with a first insulating sheath 32, and the second conductor 4 is provided with a second insulating sheath 42. The end of the first insulating sheath 32 corresponding to the first bare wire end 31 is located inside the potting compound 7, and the end of the second insulating sheath 42 corresponding to the second bare wire end 41 is located inside the potting compound 7. This prevents the first bare wire end 31 and the second bare wire end 41 from being exposed to the outside. That is, it is equivalent to the first bare wire end 31 being inserted into the potting compound 7 at a greater depth, so that the end of the first insulating sheath 32 corresponding to the first bare wire end 31 is sunk into the potting compound 7. Similarly, the end of the second insulating sheath 42 corresponding to the second bare wire end 41 is also sunk into the potting compound 7. This allows the potting compound 7 to effectively protect the first bare wire end 31 and the second bare wire end 41, and prevents the first bare wire end 31 and the second bare wire end 41 from being easily oxidized.

[0024] Furthermore, such as Figure 1 As shown, the upper part of the outer shell 1 has a mounting hole 11, so the outer shell 1 can be fixed to the outer shell of the heating element by screws. The screws pass through the mounting hole 11, so that the outer shell 1 can be attached to the outer shell of the heating element. The heat generated by the heating element is transferred to the flux 6 and the low melting point alloy wire 2 through the outer shell 1.

[0025] In the process of assembling the thermal fuse of this utility model, the first bare wire end 31 and the second bare wire end 41 can be passed through the through hole 501 first, then the low melting point alloy wire 2 can be welded to the first bare wire end 31 and the second bare wire end 41, then the liquid flux 6 can be injected into the receiving cavity 101, and then the low melting point alloy wire 2 can be quickly placed into the receiving cavity 101. After the flux 6 cools down, it can well wrap the low melting point alloy wire 2, and then the potting compound 7 can be formed.

Claims

1. A thermal fuse, comprising a housing (1) and a low-melting-point alloy wire (2), wherein a receiving cavity (101) is formed within the housing (1), the low-melting-point alloy wire (2) is disposed within the receiving cavity (101), a fluxing agent (6) is disposed within the receiving cavity (101), and the fluxing agent (6) is disposed on the outside of the low-melting-point alloy wire (2), characterized in that: It also includes a first conductor (3) and a second conductor (4), the first conductor (3) having a first bare wire end (31) and the second conductor (4) having a second bare wire end (41), the first bare wire end (31) and the second bare wire end (41) being electrically connected to the left and right ends of the low melting point alloy wire (2), respectively, and a mounting cavity (102) is formed inside the outer shell (1), the upper end of the mounting cavity (102) being connected to the receiving cavity (101), the mounting cavity (102) being connected to the receiving cavity (101) being connected to the receiving cavity (101) being connected to the receiving cavity (102 ... 2) The lower end of the shell (1) is through the outer shell (1). The mounting cavity (102) is provided with a breathable ceramic block (5). The upper end of the breathable ceramic block (5) is connected to the lower side of the flux (6). The mounting cavity (102) is provided with a potting compound (7). The potting compound (7) is located on the lower side of the flux (6). The breathable ceramic block (5) passes through the potting compound (7). The first wire (3) and the second wire (4) pass through the potting compound (7).

2. The thermal fuse according to claim 1, characterized in that: The breathable ceramic block (5) has a cover (51) and an air outlet column (52). The upper end of the air outlet column (52) is integrally connected to the lower side of the cover (51). The fluxing agent (6) and the potting compound (7) are separated by the cover (51). The air outlet column (52) passes through the potting compound (7). The first bare wire end (31) and the second bare wire end (41) pass through the cover (51).

3. The thermal fuse according to claim 2, characterized in that: A stepped portion (1011) is formed between the accommodating cavity (101) and the mounting cavity (102), and the left and right ends of the cover portion (51) are respectively attached to the lower side of the corresponding stepped portion (1011).

4. The thermal fuse according to claim 1, characterized in that: The first conductor (3) is provided with a first insulating sheath (32), and the second conductor (4) is provided with a second insulating sheath (42). The end of the first insulating sheath (32) corresponding to the first bare wire end (31) is located in the potting compound (7), and the end of the second insulating sheath (42) corresponding to the second bare wire end (41) is located in the potting compound (7).

5. The thermal fuse according to claim 1, characterized in that: The upper part of the outer casing (1) has a mounting hole (11).

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