Miniature patch fuse with high welding area and strength

Abstract

The utility model relates to the field of electronic components, in particular to a miniature patch fuse with high welding area and strength. The miniature patch fuse comprises: a substrate; the inner electrode is arranged on one side surface of the substrate; the protection layer and the inner electrode are located on the same side face of the substrate, and the protection layer covers the inner electrode; the end electrodes are arranged at the two ends of the substrate, the inner electrode and the protective layer, and the upper surface and the lower surface of each end electrode are provided with pressing grooves of slope structures. According to the invention, the phenomena of insufficient soldering of the bonding pad and unsoldering in SMT assembly can be effectively reduced, and reliable connection between the fuse and the circuit board in the long-term use process is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electronic components, in particular to a micro-surface mount fuse with high soldering area and strength. BACKGROUND

[0002] With the progress of science and technology, the development of the times and the increasing demand of people for various electronic products, the requirements for fuses are also getting higher and higher. Fuse is a kind of one-time component used for protecting circuit by being connected in series on electronic circuit. When the current exceeds the specified value, the heat generated by the fuse itself exceeds the heat dissipation, the temperature of the fuse rises above its melting point, thereby the fuse melts and breaks the circuit, which is a kind of circuit protection component. Surface mount fuse is one of the fuses which can be soldered on electronic circuit board by reflow soldering, and is widely used in lithium batteries, household appliances, computers and various electrical equipment as a short circuit and overcurrent protector, and is one of the most commonly used protection devices.

[0003] At present, the surface mount fuse generally adopts alumina ceramic substrate to print the fuse body and electrode, forms a protective layer by resin or glass coating, and finally the product is immersed in silver, electroplated or sputtered with silver, nickel and tin to form end electrodes, thereby connecting the inner electrodes to form a surface mount fuse as a whole. The surface mount fuse has certain limitations in the structure of end electrodes. For example, during the soldering process, due to the insufficient contact area and link stability between the end electrodes and the circuit board, it may cause problems such as false soldering and SMT (Surface Mount Technology) assembly disconnection, thereby affecting the electrical performance and reliability of the fuse, and even causing failure of the entire circuit system. CONTENT OF THE INVENTION

[0004] The purpose of the present application is to overcome the above technical problems, and provide a micro-surface mount fuse with high soldering area and strength, which can effectively reduce the occurrence of false soldering and SMT assembly disconnection, and ensure the reliable connection of the fuse with the circuit board during long-term use.

[0005] The present application provides a micro-surface mount fuse with high soldering area and strength, which adopts the following scheme:

[0006] A micro-surface mount fuse with high soldering area and strength, comprising: a substrate; an inner electrode arranged on one side of the substrate; a protective layer arranged on the same side of the substrate as the inner electrode and covering the inner electrode; and end electrodes arranged at both ends of the substrate, the inner electrode and the protective layer, and a slope structure pressure groove is arranged on the upper and lower surfaces of the end electrodes.

[0007] By adopting the technical scheme, the pressure groove is arranged on the end electrode, so that the solder can be better filled in the micro groove formed by the pressure groove during the welding process, and the pressure groove is arranged in a slope structure, so that the soldering effect is increased to form a more firm welding point, effectively reducing the occurrence of virtual welding and SMT assembly disconnection, and ensuring the reliable connection of the fuse with the circuit board during long-term use. In addition, the pressure groove increases the contact area of the end electrode and the circuit board pad, reduces the contact resistance, so that the current can flow more smoothly through the fuse, reduces the heating phenomenon, and improves the performance and reliability of the fuse. Therefore, by arranging the pressure groove on the end electrode, the overall performance and service life of the micro-surface mount fuse can be significantly improved.

[0008] Optionally, the product identification is arranged on the side of the substrate away from the inner electrode.

[0009] By adopting the technical scheme, the product identification is arranged on the side of the substrate away from the inner electrode, so that the product identification can be increased without affecting the electrical performance.

[0010] Optionally, the product protection layer is formed by high-temperature sintering of glass paste and / or high-temperature resistant polymer.

[0011] By adopting the technical scheme, the product protection layer is formed by high-temperature sintering of glass paste and / or high-temperature resistant polymer, so that the heat resistance and mechanical strength of the product identification can be improved, the good adhesion and stability can be ensured in a high-temperature environment, the product identification can be effectively prevented from falling off or being damaged, and the service life and reliability of the product can be prolonged.

[0012] Optionally, the pressure groove extends along the length direction of the fuse product on the upper and lower surfaces of the end electrode.

[0013] By adopting the technical scheme, the pressure groove extends along the length direction of the fuse product on the upper and lower surfaces of the end electrode, so that the contact area and stability between the end electrode and the external welding point can be effectively improved, and the mechanical strength and electrical connection reliability of the fuse can be enhanced.

[0014] Optionally, two pressure grooves are arranged on each of the upper and lower surfaces of the end electrode.

[0015] By adopting the technical scheme, two pressure grooves are arranged on each of the upper and lower surfaces of the end electrode, so that the stability of the fuse during the welding process can be effectively increased, the displacement or falling off phenomenon caused by thermal stress can be prevented, and the reliability of the welding point is improved. Specifically, the design of multiple pressure grooves increases the contact area between the fuse and the circuit board during welding, enhances the mechanical connection strength, and further reduces the risk of virtual welding.

[0016] Optionally, the depth of the pressure groove near the edge is 1 / 4-2 / 5 of the thickness of the end electrode, and the depth of the pressure groove far from the edge is 1 / 6-1 / 5 of the thickness of the end electrode; the width of the pressure groove is 1 / 6-1 / 4 of the width of the end electrode, and the length of the pressure groove is 1 / 2-2 / 3 of the length of the end electrode.

[0017] By adopting the above technical solution, the specific depth, width and length of the pressure groove can significantly improve the contact area and mechanical strength between the micro patch fuse and the circuit board. Specifically, the depth of the pressure groove near the edge of the slope structure is 1 / 4-2 / 5 of the thickness of the end electrode, and the depth of the pressure groove far from the edge is 1 / 6-1 / 5 of the thickness of the end electrode, which ensures that the pressure groove has sufficient depth to enhance the bonding force between the end electrode and the substrate, thereby improving the stability of the entire fuse structure. The width of the pressure groove is 1 / 6-1 / 4 of the width of the end electrode, so that the pressure groove neither excessively affects the overall conductive performance of the end electrode nor provides the necessary mechanical support. The length of the pressure groove is 1 / 2-2 / 3 of the length of the end electrode, which ensures uniform distribution of the pressure groove on the entire end electrode, further enhancing the tensile and bending resistance of the end electrode. These designs collectively improve the reliability and service life of the micro patch fuse.

[0018] Optionally, the inner electrode is a melt formed by printing a conductive paste onto the substrate and sintering.

[0019] By adopting the above technical solution, the inner electrode is a melt formed by printing a conductive paste onto the substrate and sintering, which improves the bonding strength between the inner electrode and the substrate and ensures good electrical connection performance. At the same time, this manufacturing method is simple and low in cost, which is conducive to large-scale production.

[0020] Optionally, the end electrode is formed by immersing both ends of the combination of the substrate, the inner electrode and the protective layer into a conductive paste and then drying and sintering.

[0021] By adopting the above technical solution, the end electrode is formed by immersing both ends of the combination of the substrate, the inner electrode and the protective layer into a conductive paste and then drying and sintering, which makes the bonding between the end electrode and the substrate, the inner electrode and the protective layer more firm, improving the overall structural stability and reliability of the fuse. At the same time, this method simplifies the manufacturing process and reduces production costs.

[0022] Optionally, the conductive paste is silver paste or other low-resistivity conductive paste.

[0023] By adopting the technical scheme, the conductive performance and reliability of the end electrode can be improved significantly by using silver paste or other low-resistivity conductive paste. Silver or other low-resistivity material has excellent conductivity and corrosion resistance, which can ensure the stability and safety of the fuse under long-time work. Meanwhile, the processing technology of silver paste or other low-resistivity material is mature and easy to control, which helps to improve the production efficiency and quality stability of the product.

[0024] Optionally, the protective layer is provided in two layers and is formed of resin or glass material.

[0025] By adopting the technical scheme, the protective layer is provided in two layers and is formed of resin or glass material, which can significantly improve the environmental performance of the fuse, such as moisture resistance and mechanical strength, thereby improving the reliability and service life of the product. Specifically, the double-layer structure can better isolate the internal electrode and the external environment, preventing the intrusion of moisture and other corrosive substances, and the use of resin or glass material further enhances the protection effect.

[0026] In summary, the present application includes at least one of the following beneficial technical effects:

[0027] 1. The inner electrode and the protective layer are provided on the same side of the substrate, and are wrapped by the end electrode at both ends, which improves the connection strength between the end electrode and the substrate, effectively preventing the end electrode from falling off during long-term use;

[0028] 2. The upper and lower surfaces of the end electrode are provided with inclined pressure grooves, which increases the contact area between the end electrode and the substrate, and enables the solder and the end electrode to be better combined during the welding process, forming a more secure welding connection;

[0029] 3. By providing a product identification, the product information is clearly displayed, which facilitates identification and management during production and maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A perspective structural schematic view of the micro paster fuse with high welding area and strength disclosed in the embodiments of the present application;

[0031] Figure 2 An exploded structural schematic view of the micro paster fuse with high welding area and strength disclosed in the embodiments of the present application.

[0032] MARKS DESCRIPTION:

[0033] 10, substrate; 20, inner electrode; 30, protective layer; 40, product identification; 50, end electrode; 51, pressure groove. DETAILED DESCRIPTION

[0034] The terminology used in the following embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in the description of the embodiments of the application and the appended claims, the singular forms "a", "an" and "the" are intended to include both singular and plural forms, unless the context clearly indicates otherwise. It will be further understood that the terms "and / or", as used in the description of the embodiments of the application, signify and include any and all possible combinations of one or more of the associated listed items.

[0035] Hereinafter, the terms "first", "second" are only for the purpose of description, and cannot be understood as implying or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified.

[0036] The technical solutions of the embodiments of the present application are described in detail below in combination with the drawings.

[0037] Referring to Figure 1 and Figure 2 The micro patch fuse with high welding area and strength disclosed in the embodiments of the present application comprises a substrate 10, an inner electrode 20, a protective layer 30, a product identification 40 and an end electrode 50.

[0038] Among them, the substrate 10 is used to support the structure of the entire fuse, the inner electrode 20 is arranged on one side of the substrate 10, the protective layer 30 is arranged on the same side of the substrate 10 as the inner electrode 20 and covers the inner electrode 20, and plays a protective role. The product identification 40 is arranged on the side of the substrate 10 away from the inner electrode 20, and plays a role of increasing product identifiability and aesthetics.

[0039] Referring to Figure 2 The end electrode 50 is arranged at both ends of the substrate 10, the inner electrode 20 and the protective layer 30, and a pressing groove 51 is arranged on the upper and lower surfaces of the end electrode 50, so that the solder can be better filled in the micro recess formed by the pressing groove 51, forming a more firm welding point, effectively reducing the occurrence of false welding and SMT assembly debonding phenomenon, and ensuring the reliable connection of the fuse with the circuit board during long-term use. It is worth mentioning here that the pressing groove 51 is a slope structure, which is between 45-60 degrees, so as to increase the soldering effect and further optimize the welding effect to enhance the stability of the overall structure.

[0040] Specifically, the substrate 10 is made of ceramic material, i.e. ceramic substrate, to ensure the stability and reliability of the substrate 10 at high temperature. Of course, the substrate 10 can also be made of other high insulating materials, which are not limited herein. The inner electrode 20 is a specific pattern melt formed by sintering a single layer or multiple layers of conductive paste (gold or silver paste or other low resistivity conductive paste) on the substrate 10.

[0041] Referring to Figure 2 The protective layer 30 is a protective layer 30 formed by screen printing glass paste or resin on the inner electrode 20 and then sintering at high temperature to cover and encapsulate the inner electrode 20, so as to effectively prevent the influence of the external environment on the inner electrode 20 and enhance the environmental adaptability of the fuse. In the present embodiment, the protective layer 30 is provided in two layers, but the number of layers is not limited herein and can be set according to the specifications of the fuse.

[0042] The product identification 40 is a specific pattern (various patterns) formed by screen printing glass paste or high-temperature-resistant polymer material on the other side of the ceramic substrate 10 and then sintering at high temperature. The end electrode 50 is silver paste immersed in both ends of the fuse body (both ends of the substrate 10, the inner electrode 20 and the protective layer 30), dried and sintered, and then two pressure grooves 51 are added to the upper and lower surfaces, respectively, and then silver, nickel or tin is formed by electroplating or sputtering to form the end electrode 50, thereby connecting the inner electrode 20 to form a micro patch fuse as a whole.

[0043] The depth of the pressure groove 51 of the slope structure near the edge is 1 / 4-2 / 5 of the thickness of the end electrode, the depth far from the edge is 1 / 6-1 / 5 of the thickness of the end electrode, the width of the pressure groove 51 is 1 / 6-1 / 4 of the width of the end electrode 50, the length of the pressure groove 51 is 1 / 2-2 / 3 of the length of the end electrode 50, and the pressure groove 51 extends along the length direction of the fuse product on the upper and lower surfaces of the end electrode 50, and two pressure grooves 51 are arranged on the upper and lower surfaces of the end electrode 50, respectively, thereby increasing the contact area of the end electrode 50 and the substrate 10, so that the end electrode 50 and the substrate 10 are better combined and more firm, and the contact area of the end electrode 50 and the circuit board pad is also increased. In the soldering process, the large contact area can make the solder and the end electrode 50 better combined to form a more firm soldering connection.

[0044] In addition, according to the resistance law formula R=pL / S, R is the resistance, P is the resistivity, L is the length of the conductor, and S is the cross-sectional area of the conductor. Since the pressure groove 51 increases the cross-sectional area S, the contact resistance between the end electrode 50 and the circuit board pad can be reduced, the energy loss of the current in the transmission process can be reduced, the current can flow more smoothly through the fuse, and the normal work of the circuit is ensured.

[0045] In summary, the micro paster fuse with high welding area and strength disclosed by the embodiments of the application has the advantages that: the inner electrode 20 and the protective layer 30 are arranged on the same side of the substrate 10, and the two ends thereof are wrapped by the end electrode 50, so that the connection strength between the end electrode 50 and the substrate 10 is improved; the upper and lower surfaces of the end electrode 50 are provided with the slope structure pressing groove 51, so that the contact area between the end electrode 50 and the substrate 10 is increased, the solder can be combined with the end electrode 50 better in the welding process, and a more firm welding connection is formed; the product identification 40 is arranged, so that the product information is clearly displayed, and the identification and management in the production and maintenance process are facilitated.

[0046] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the application.

Claims

1. A micro-attaching fuse having a high welding area and strength, characterized by, The application relates to a fuse product, which comprises the following parts: a substrate (10); an inner electrode (20) arranged on one side of the substrate (10); a protective layer (30) arranged on the same side of the substrate (10) as the inner electrode (20) and covering the inner electrode (20); and end electrodes (50) arranged at both ends of the substrate (10), the inner electrode (20) and the protective layer (30), and provided with slope-structured pressing grooves (51) on the upper and lower surfaces of the end electrodes (50). The application further comprises a product mark (40) arranged on the side of the substrate (10) away from the inner electrode (20). The product mark (40) layer is formed by high-temperature sintering of glass paste or high-temperature-resistant polymer.

2. The micro-attache fuse of claim 1, wherein, The pressing grooves (51) extend along the length direction of the fuse product on the upper and lower surfaces of the end electrodes (50). Two pressing grooves (51) are arranged on the upper and lower surfaces of the end electrodes (50) respectively.

3. The micro-attache fuse of claim 2, wherein, The depth of the pressing grooves (51) near the edge is 1 / 4-2 / 5 of the thickness of the end electrodes (50), and the depth of the pressing grooves (51) away from the edge is 1 / 6-1 / 5 of the thickness of the end electrodes (50); the width of the pressing grooves (51) is 1 / 6-1 / 4 of the width of the end electrodes (50), and the length of the pressing grooves (51) is 1 / 2-2 / 3 of the length of the end electrodes (50).

4. The micro-attache fuse of claim 1, wherein, The inner electrode (20) is a melt formed by printing conductive paste on the substrate (10) and sintering.

5. The micro-attache fuse of claim 4, wherein, The end electrodes (50) are formed by dipping the two ends of the combination of the substrate (10), the inner electrode (20) and the protective layer (30) into conductive paste, drying and sintering.

6. The micro-attache fuse of claim 1, wherein, The conductive paste is silver paste.

7. The micro-attache fuse of claim 1, wherein, The protective layer (30) is arranged in two layers, and is formed of resin or glass material.

8. The micro-attache fuse of claim 1, wherein, ​ 9. The micro-attache fuse of claim 7, wherein, ​ 10. The micro-attache fuse of claim 1, wherein, ​

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