Coated type fuse resistor

Abstract

The utility model discloses a coating type fuse resistor, including base layer, resistance layer, gradient fuse layer, protective layer and electrode plate, the resistance layer is covered in the upper surface of base layer through the mode of sintering, gradient fuse layer is located the upper surface of resistance layer, gradient fuse layer is compounded by heat conduction layer, vaporization layer and insulating layer who sets gradually from bottom to top in proper order, heat conduction layer is coated on resistance layer, the protective layer covers gradient fuse layer and resistance layer exposed area, the electrode plate is provided with a pair and is located base layer both ends respectively. The utility model discloses through multilayer function layer integration design, successfully realizes the miniaturization of fuse resistor, innovatively adopts gradient fuse structure and spiral groove guide technology, and the response speed and action accuracy of overcurrent protection are improved significantly, and the whole structure eliminates the risk of fusing spatter thoroughly, solves the problems, such as big volume of traditional device, response lag, poor environmental adaptability and maintenance difficulty.

Description

Technical Field

[0001] This utility model belongs to the field of resistor technology, specifically relating to coated fusible resistors. Background Technology

[0002] A fusible resistor is a special component that integrates a resistor and a fuse. Its functions are: it can work normally for a long time under rated operating voltage or current conditions and be used as a normal resistor; when the voltage or current in the circuit exceeds the rated operating voltage or current, the fusible resistor overheats and melts, thus protecting the circuit.

[0003] Traditional fusible resistors require separate installation of the resistor element and fuse wire, resulting in a large resistor footprint and a long heat conduction path leading to a longer response time. They also suffer from low fusing accuracy and poor environmental stability.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0005] The purpose of this invention is to provide a coated fusible resistor that can solve the problems of large space occupation, long response time due to long heat conduction path, low fusing accuracy and poor environmental stability of resistors.

[0006] To achieve the above objectives, the technical solution provided by a specific embodiment of this utility model is as follows:

[0007] A coated fusible resistor includes a substrate layer, a resistive layer, a gradient fusing layer, a protective layer, and electrode plates. The resistive layer is sintered onto the upper surface of the substrate layer. The gradient fusing layer is disposed on the upper surface of the resistive layer and is composed of a thermally conductive layer, a vaporization layer, and an insulating layer arranged sequentially from bottom to top. The thermally conductive layer is coated on the resistive layer. The protective layer covers the exposed areas of the gradient fusing layer and the resistive layer. A pair of electrode plates are disposed at both ends of the substrate layer and are electrically connected to the resistive layer.

[0008] In one or more embodiments of this utility model, the substrate layer is an insulating substrate made of ceramic or glass fiber material.

[0009] In one or more embodiments of this utility model, the upper surface of the substrate layer is provided with a microcrack mesh by laser.

[0010] In one or more embodiments of this utility model, the upper surface of the resistive layer is laser-drilled with a plurality of spiral grooves, and the bottom of the thermally conductive layer is integrally formed with a plurality of spiral protrusions, which are embedded in the plurality of spiral grooves.

[0011] In one or more embodiments of this utility model, the thermally conductive layer is made of copper powder and bismuth-tin high thermal conductivity alloy, the vaporization layer is made of indium-tin alloy containing microcapsule foaming agent, and the insulating layer is made of boron nitride ceramic.

[0012] In one or more embodiments of this utility model, the amount of microcapsule foaming agent added to the vaporization layer is 5-8 wt%, and the thickness ratio of the thermally conductive layer, the vaporization layer and the insulating layer is 2:3:1.

[0013] In one or more embodiments of this utility model, the protective layer has a plurality of micropores formed through it, and the micropores are arranged in an array.

[0014] In one or more embodiments of this utility model, the protective layer is added with 0.5-1.2wt% thermochromic material, and the inner wall of the micropores is covered with a hydrophobic nanofilm with a contact angle >150 degrees.

[0015] In one or more embodiments of this utility model, mounting grooves are provided at the edges of both ends of the substrate layer, the horizontal plate of the electrode plate is pressed against the groove wall of the mounting groove, and wiring terminals are integrally formed on the outer side wall of the vertical plate of the electrode plate.

[0016] In one or more embodiments of this utility model, a nano-riveting layer is provided at the interface between the resistive layer and the electrode plate, and the nano-riveting layer is composed of vertically oriented conductive nanowires.

[0017] Compared with existing technologies, this utility model achieves miniaturization of the fusible resistor through multi-layer functional integrated design; it innovatively adopts a gradient fusing structure and spiral groove guiding technology, which significantly improves the response speed and action accuracy of overcurrent protection; the overall structure completely eliminates the risk of fusible splashing and solves the problems of large size, slow response, poor environmental adaptability and difficult maintenance of traditional devices. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1This is a schematic diagram of a coated fusible resistor in one embodiment of the present invention;

[0020] Figure 2 This is a cross-sectional view of a coated fusible resistor in one embodiment of the present invention;

[0021] Figure 3 An explosion of a coated fusible resistor in one embodiment of this utility model. Figure 1 ;

[0022] Figure 4 An explosion of a coated fusible resistor in one embodiment of this utility model. Figure 2 ;

[0023] Figure 5 This is a cross-sectional view of a coated fusible resistor in one embodiment of the present invention;

[0024] Figure 6 This utility model Figure 5 A schematic diagram of point A in the middle.

[0025] Explanation of key figure labels:

[0026] 1-Substrate layer, 11-Microcrack network, 12-Mounting groove, 2-Resistant layer, 21-Helical groove, 3-Gradient fusing layer, 31-Thermal conductive layer, 32-Vaporization layer, 33-Insulating layer, 34-Helical protrusion, 4-Protective layer, 41-Micropore, 5-Electrode plate, 51-Terminal, 6-Nano riveting layer. Detailed Implementation

[0027] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0028] like Figures 1-6 As shown, a coated fusible resistor in one embodiment of the present invention includes a substrate layer 1, a resistive layer 2, a gradient fusible layer 3, a protective layer 4, and an electrode plate 5. The resistive layer 2 is sintered over the upper surface of the substrate layer 1. The gradient fusible layer 3 is disposed on the upper surface of the resistive layer 2. The gradient fusible layer 3 is composed of a thermally conductive layer 31, a vaporization layer 32, and an insulating layer 33 arranged sequentially from bottom to top. The thermally conductive layer 31 is coated on the resistive layer 2. The protective layer 4 covers the gradient fusible layer 3 and the exposed area of ​​the resistive layer 2. A pair of electrode plates 5 are disposed at both ends of the substrate layer 1, and the electrode plates 5 are electrically connected to the resistive layer 2.

[0029] The principle of this coated fusible resistor is as follows: the resistor is connected to the outside via electrode plate 5, and current flows through electrode plate 5 onto resistive layer 2. When the current is below the rated value, the heat generated in resistive layer 2 is rapidly transferred through heat-conducting layer 31 and dissipated through protective layer 4, keeping the temperature of resistive layer 2 below the threshold. When the current is above the rated value, the current transferred to resistive layer 2 is overloaded, causing the temperature of resistive layer 2 to rise sharply. Heat-conducting layer 31 accelerates heat transfer, causing the temperature of vaporization layer 32 to exceed the vaporization temperature. The vaporization of vaporization layer 32 causes gas expansion, which breaks through insulation layer 33 and is finally discharged through protective layer 4. The rapid reaction of vaporization layer 32 under heat enables rapid response to current overload. Furthermore, the direct integration of resistive layer 2 and gradient fusible layer 3 reduces the space occupied by the resistor and shortens the response time. The rapid thermal equilibrium achieved by heat-conducting layer 31 and the rapid expansion of vaporization layer 32 solve the problems of low fusing accuracy and poor environmental stability.

[0030] Specifically, the substrate 1 is an insulating substrate made of ceramic or glass fiber material, which enables the substrate 1 to provide mechanical support while also providing insulation, and at the same time, it can quickly conduct heat away from the resistive layer 2 through its thermal conductivity.

[0031] like Figure 3 As shown, the upper surface of the substrate layer 1 is laser-cut with microcrack mesh 11, so that when the resistive layer 2 is sintered on the substrate layer 1, the microcrack mesh 11 is provided between them, so as to effectively buffer thermal stress through the microcrack mesh 11.

[0032] like Figure 3 and Figure 4 The upper surface of the resistive layer 2 is laser-cut with multiple spiral grooves 21, and the bottom of the heat-conducting layer 31 is integrally formed with multiple spiral protrusions 34, which are embedded in the spiral grooves 21. Through the cooperation of the spiral protrusions 34 and the spiral grooves 21, the contact area between the resistive layer 2 and the heat-conducting layer 31 is effectively increased, thereby greatly improving the heat transfer efficiency.

[0033] Preferably, the thermally conductive layer 31 is made of a copper powder and bismuth-tin high thermal conductivity alloy to accelerate heat transfer to the vaporization layer 32. The vaporization layer 32 is made of an indium-tin alloy containing a microencapsulated foaming agent, which causes the vaporization layer 32 to expand and vaporize rapidly upon heating. The insulating layer 33 is made of boron nitride ceramic and prevents short circuits caused by molten metal splashing.

[0034] Preferably, the amount of microcapsule foaming agent added to the vaporization layer 32 is 5-8 wt%, and the thickness ratio of the thermally conductive layer 31, the vaporization layer 32 and the insulating layer 33 is 2:3:1.

[0035] like Figures 1-6As shown, the protective layer 4 has multiple micropores 41 that are formed through it. The micropores 41 are arranged in an array so that the gas generated when the heat-conducting layer 31 melts can be discharged through the micropores 41.

[0036] Preferably, the protective layer 4 contains 0.5-1.2 wt% of a thermochromic material, which is a cobalt salt complex, so that it changes color when heated and the melting state is visible to the naked eye. The inner wall of the micropores 41 is covered with a hydrophobic nanofilm with a contact angle >150 degrees, which effectively blocks external moisture from entering through the micropores 41. This allows the micropores 41 to quickly conduct heat and exhaust air without causing the resistor to become damp, effectively extending the resistor's service life.

[0037] like Figures 2-5 As shown, mounting grooves 12 are provided at the edges of both ends of the substrate layer 1. The horizontal plate of the electrode plate 5 is pressed onto the groove wall of the mounting groove 12. A wiring terminal 51 is integrally formed on the outer side wall of the vertical plate of the electrode plate 5. The resistor is connected to the external circuit through the wiring terminal 51.

[0038] like Figure 5 Combination Figure 6 As shown, a nano-riveting layer 6 is provided at the interface where the resistive layer 2 and the electrode plate 5 contact. The nano-riveting layer 6 is composed of vertically oriented conductive nanowires. The nano-riveting layer 6 connects the resistive layer 2 and the electrode plate 5, improving their shear resistance, preventing mechanical vibration from causing the resistive layer 2 and the electrode plate 5 to detach, and ensuring stable conductivity between the resistive layer 2 and the electrode plate 5.

[0039] In use, the resistor is connected to the outside via electrode plate 5, and current flows through electrode plate 5 onto resistive layer 2. When the current is below the rated value, the heat generated in resistive layer 2 is rapidly transferred through heat-conducting layer 31 and dissipated through protective layer 4, keeping the temperature of resistive layer 2 below the threshold. When the current is above the rated value, the current transferred to resistive layer 2 is overloaded, causing the temperature of resistive layer 2 to rise sharply. Heat-conducting layer 31 accelerates heat transfer, causing the temperature of vaporization layer 32 to exceed the vaporization temperature. Vaporization of vaporization layer 32 causes gas expansion, which breaks through insulating layer 33 and is finally discharged through micropores 41. The rapid reaction of vaporization layer 32 under heat enables a rapid response to current overload.

[0040] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0041] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A coated fusible resistor, characterized in that, include: Matrix layer; The resistive layer is sintered to cover the upper surface of the substrate layer; A gradient fracturing layer is disposed on the upper surface of the resistive layer. The gradient fracturing layer is composed of a heat-conducting layer, a vaporization layer and an insulating layer arranged sequentially from bottom to top. The heat-conducting layer is coated on the resistive layer. The protective layer covers the exposed areas of the gradient fuse layer and the resistive layer; A pair of electrode plates are provided, each located at one end of the substrate layer, and the electrode plates are electrically connected to the resistive layer.

2. The coated fusible resistor according to claim 1, characterized in that, The substrate layer is an insulating substrate made of ceramic or glass fiber material.

3. The coated fusible resistor according to claim 1, characterized in that, The upper surface of the substrate layer is laser-grouted with microcracks.

4. The coated fusible resistor according to claim 1, characterized in that, The upper surface of the resistive layer is laser-cut with multiple spiral grooves, and the bottom of the thermally conductive layer is integrally formed with multiple spiral protrusions, which are embedded in the multiple spiral grooves.

5. The coated fusible resistor according to claim 1, characterized in that, The insulating layer is made of boron nitride ceramic.

6. The coated fusible resistor according to claim 5, characterized in that, The thickness ratio of the heat-conducting layer, the vaporization layer, and the insulating layer is 2:3:

1.

7. The coated fusible resistor according to claim 1, characterized in that, The protective layer has multiple micropores that penetrate through it, and the micropores are arranged in an array.

8. The coated fusible resistor according to claim 7, characterized in that, The inner wall of the micropores is covered with a hydrophobic nanofilm with a contact angle >150 degrees.

9. The coated fusible resistor according to claim 1, characterized in that, Mounting grooves are provided at the edges of both ends of the substrate layer. The horizontal plate of the electrode plate is pressed against the groove wall of the mounting groove. A wiring terminal is integrally formed on the outer side wall of the vertical plate of the electrode plate.

10. The coated fusible resistor according to claim 1, characterized in that, The interface between the resistive layer and the electrode plate is provided with a nano-riveting layer, which is composed of vertically oriented conductive nanowires.

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