Integrally-formed surface-mounted inductor and manufacturing method
By setting the electrode stripping position on the external electrode of the high-current power inductor, the problem of inductor prone to insulation damage and voltage deterioration in the most fragile places is solved, and the effect of improving the voltage withstandability of the inductor is achieved.
Patent Information
- Application Number
- CN202510333375.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2025-05-30
AI Technical Summary
Existing high-current power inductors are prone to insulation damage and voltage deterioration in the most vulnerable places, especially at the shortest distance between the outermost ring of the built-in coil and the external electrode.
By setting the electrode stripping position on the external electrode of the inductor, the original external electrode is located at the position where the inductor potential difference is the largest, thereby eliminating the potential risks of insulation damage and voltage deterioration. The method includes forming a coil and granulated powder into a molded body, and the end of the coil leaks out from the molded body, applying insulating resin to the surroundings of the molded body, peeling the insulating resin through laser light, adjusting the electrode range, and plating copper or conductive glue on the electrode peeling position, and then plating Ni and Sn to form an external electrode.
By setting the electrode stripping position, the voltage withstandability of the inductor is effectively improved, eliminating the problem that insulation damage and insulation deterioration are prone to occur at the shortest distance between the outermost ring of the built-in coil and the external electrode.
Smart Images
Figure CN120072480A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of surface mount inductors, and specifically to an integrally formed surface mount inductor and a manufacturing method thereof. Background Art
[0002] For high-current power inductors used in circuits, their granulated powder is composed of a mixture of metal magnetic powder and resin. A hollow coil wound with copper wire is covered and then integrally formed, so that the ends of the coil protrude from both ends of the formed body to form external electrodes.
[0003] In order to handle high currents, the magnetic powder of the inductor is generally changed from a ferrite material to a metal material (metal magnetic powder). For the so-called external electrodes, in one method, a conductive glue is applied, and after hardening, Ni and Sn are plated on its surface. In another method, after copper plating, Ni and Sn are plated on it.
[0004] Because metal materials are used, the inductor can handle high currents, but at the same time, the insulation resistance decreases compared with ferrite materials.
[0005] Generally, the structure of an inductor is formed by granulated powder of a metal material, with upper and lower layers of coils built in. The hidden danger of this structure is that short circuits may occur in the weakest places (generally, insulation breakdown and voltage withstand deterioration are likely to occur at the positions with the largest potential difference).
[0006] If it is an L-shaped electrode, there are two positions where insulation breakdown and voltage withstand deterioration are likely to occur. One is the position where the distance between the outermost circle of the built-in lower-layer coil and the bottom electrode is the shortest, and the other is the position where the distance between the outermost circle of the built-in coil and the side electrode is the shortest.
[0007] The same is true for the bottom electrode. Insulation breakdown and insulation deterioration are likely to occur at the position where the shortest distance between the outermost circle of the built-in coil and the bottom electrode. Summary of the Invention
[0008] The purpose of the present invention is to provide an integrally formed surface mount inductor and a manufacturing method thereof to solve the problems raised in the above background art.
[0009] To achieve the above purpose, the present invention provides the following technical solution: An integrally formed surface mount inductor includes a formed body integrally formed by a coil and granulated powder. The ends of the coil protrude from the formed body, and an external electrode is formed on the outside of the formed body; an electrode peeling position for changing the electrode range is formed on the side and / or bottom surface of the external electrode.
[0010] The integrally formed surface mount inductor as described above: The external electrode includes a side electrode, and a first peeling portion is formed on the bottom surface of the side electrode and / or a second peeling portion is formed on the side surface of the side electrode.
[0011] The integrally formed surface mount inductor as described above: The first peeling portion and the second peeling portion are arranged in an arc shape or a rectangular shape.
[0012] The integrally formed surface mount inductor as described above: The peeling width of the first peeling portion is less than or equal to the width of the side electrode located at the bottom surface of the formed body.
[0013] The integrally formed surface mount inductor as described above: The external electrode includes a bottom surface electrode, and a third peeling portion is formed on the bottom surface electrode.
[0014] The integrally formed surface mount inductor as described above: The third peeling portion is arranged in an arc shape or a rectangular shape.
[0015] The integrally formed surface mount inductor as described above: The peeling width of the third peeling portion is less than or equal to the width of the bottom surface electrode.
[0016] A manufacturing method of an integrally formed surface mount inductor includes the following steps: integrally forming a coil and granulated powder to form a formed body, and the end of the coil leaks out from the formed body; applying an insulating resin around the formed body, and then peeling the insulating resin by laser to adjust the electrode range through the electrode peeling position; then plating copper or applying a conductive glue at the electrode peeling position of the formed body, and plating Ni and Sn on the position where copper is plated or the conductive glue is applied to form an external electrode, so as to complete the manufacturing.
[0017] Compared with the prior art, the beneficial effect of the present invention is that: through the provided electrode peeling position, there is no electrode at the position where the original external electrode is located at the maximum potential difference of the inductor, eliminating the problem that insulation breakdown and insulation deterioration are likely to occur at the position of the shortest distance between the outermost circle of the built-in coil and the external electrode, and effectively improving the withstand voltage ability of the inductor. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic structural diagram of an integrally formed surface mount inductor (side electrode); Figure 2 It is a schematic structural diagram of an integrally formed surface mount inductor (bottom surface electrode); Figure 3 It is a schematic diagram of the electrode range of an integrally formed surface mount inductor (side electrode); Figure 4 It is a side view and an upward view comparison diagram of an integrally formed surface mount inductor (side electrode); Figure 5 It is a side view and an upward view comparison diagram of an integrally formed surface mount inductor (bottom surface electrode); Figure 6 It is a schematic structural diagram of an integrally formed surface mount inductor (side electrode) in Embodiment 1; Figure 7 Schematic diagram of the structure of Example 2 of an integrally formed surface mount inductor (side electrodes); Figure 8 Schematic diagram of the structure of Example 3 of an integrally formed surface mount inductor (side electrodes); Figure 9 Schematic diagram of the structure of Example 4 of an integrally formed surface mount inductor (side electrodes); Figure 10 Schematic diagram of the structure of Example 5 of an integrally formed surface mount inductor (side electrodes); Figure 11 Schematic diagram of the structure of Example 6 of an integrally formed surface mount inductor (bottom electrodes); Figure 12 Schematic diagram of the structure of Example 7 of an integrally formed surface mount inductor (bottom electrodes); Figure 13 Schematic diagram of the structure of Example 8 of an integrally formed surface mount inductor (bottom electrodes); Figure 14 Equivalent diagram of an integrally formed surface mount inductor (side electrodes); Figure 15 Equivalent diagram of an integrally formed surface mount inductor (bottom electrodes).
[0019] In the figure: 101 - granulated powder, 102a - side electrode, 1021a - first peeling part, 1022a - second peeling part, 1021b - third peeling part, 102b - bottom electrode, 103a - first voltage withstand vulnerable position, 103b - second voltage withstand vulnerable position, 104 - coil. Detailed implementation manners
[0020] The following will describe in detail various exemplary embodiments, features, and aspects of the present application with reference to the accompanying drawings. The same reference numerals in the drawings denote elements having the same or similar functions. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise specified.
[0021] The special term "exemplary" here means "serving as an example, embodiment, or illustration". Any embodiment described as "exemplary" here does not necessarily have to be construed as superior to or better than other embodiments.
[0022] In addition, for a better description of the present application, numerous specific details are given in the following detailed embodiments. Those skilled in the art should understand that the present application can be implemented without some specific details. In some instances, methods, means, and elements well known to those skilled in the art are not described in detail so as to highlight the gist of the present application.
[0023] Please refer to Figures 1 - 3 , wherein,Figure 1 is an inductor (side electrode), Figure 2 is an inductor (bottom electrode). Taking the inductor with side electrodes as an example, the situation of the side electrodes will be described. As Figure 3 is a schematic diagram of the side and bottom states of the molded body. In the figure, the electrodes at A, B, C, and D are respectively: A is below 0.9L; B is above 1.1L; C is above 0.5W; D is above 0.9T, where T is half of the height of the inductor and L is the length of the coil 104, and W is the width of the coil 104.
[0024] Please refer to Figures 1 - 13 , in the embodiment of the present invention, a one-piece surface mount inductor includes a molded body integrally formed by a coil 104 and granulated powder 101. The end of the coil 104 leaks out of the molded body, and an external electrode is formed on the outside of the molded body; an electrode stripping position for changing the electrode range is formed on the side and / or bottom of the external electrode. Through the provided electrode stripping position, the present invention makes the original external electrode have no electrode at the position with the largest potential difference of the inductor, eliminating the problem that insulation breakdown and insulation deterioration are likely to occur at the position of the shortest distance between the outermost circle of the built-in coil 104 and the external electrode, and effectively improving the withstand voltage ability of the inductor.
[0025] Among them, it should be noted that the electrode stripping position described here can be to remove the external electrode at the current position after the external electrode is formed; or, the insulating resin at the electrode stripping position is not removed during the manufacturing process to form an insulating part, and copper plating or other treatments are performed at other electrode stripping positions.
[0026] The coil 104 is formed by a winding method with two upper and lower layers. The coil 104 includes, but is not limited to, flat wire or round wire.
[0027] The granulated powder 101 is composed of a metal magnetic powder and a resin. Preferably, the metal magnetic powder is iron powder. Of course, in the specific implementation process, other metal powders can also be used as long as the requirements are met. This embodiment does not make specific limitations on this.
[0028] Please refer to Figure 1 , Figure 2 , Figure 4 and Figure 5 , the external electrodes of the inductor have two types. One is the side electrode 102a, which is arranged in an L-shaped structure, located on the bottom and side of the molded body and is continuous. The other is the bottom electrode 102b, which is planar and located on both sides of the bottom of the molded body.
[0029] Please refer to Figure 14 , which is an equivalent diagram of the inductor with side electrodes 102a, and has two withstand voltage vulnerable positions 103a (positions with the largest potential difference).
[0030] Please refer to Figure 15 , which is an equivalent diagram of an inductor with a bottom electrode 102b, having a breakdown-voltage vulnerable bit 103b (the position with the maximum potential difference).
[0031] Example 1 Please refer to Figure 6 . A first peeling portion 1021a is formed on the bottom surface of the side electrode 102a, and there is no peeling on the side surface of the side electrode 102a, thereby reducing the potential difference at the bottom surface position of the side electrode 102a to a certain extent and improving the breakdown voltage capability of the inductor. The first peeling portion 1021a is arranged in an arc shape, and the maximum peeling width of the first peeling portion 1021a is less than the width of the side electrode 102a located at the bottom surface of the molded body and greater than C.
[0032] Example 2 Please refer to Figure 7 . A first peeling portion 1021a is formed on the bottom surface of the side electrode 102a, and a second peeling portion 1022a is formed on the side surface of the side electrode 102a, thereby reducing the potential difference at the bottom surface position and the side surface position of the side electrode 102a to a certain extent and improving the breakdown voltage capability of the inductor. The first peeling portion 1021a is arranged in an arc shape, and the maximum peeling width of the first peeling portion 1021a is less than the width of the side electrode 102a located at the bottom surface of the molded body and greater than C. The second peeling portion 1022a is arranged in a rectangular shape.
[0033] Example 3 Please refer to Figure 8 . There is no peeling on the bottom surface of the side electrode 102a, and a second peeling portion 1022a is formed on the side surface of the side electrode 102a, thereby reducing the potential difference at the side surface position of the side electrode 102a to a certain extent and improving the breakdown voltage capability of the inductor. The second peeling portion 1022a is arranged in a rectangular shape.
[0034] Example 4 Please refer to Figure 9 . A first peeling portion 1021a is formed on the bottom surface of the side electrode 102a, and there is no peeling on the side surface of the side electrode 102a, thereby reducing the potential difference at the bottom surface position of the side electrode 102a to a certain extent and improving the breakdown voltage capability of the inductor. The first peeling portion 1021a is arranged in a rectangular shape, and the maximum peeling width of the first peeling portion 1021a is equal to the width of the side electrode 102a located at the bottom surface of the molded body and greater than C.
[0035] Example 5 Please refer to Figure 10, a first peeling portion 1021a is formed on the bottom surface of the side electrode 102a, and a second peeling portion 1022a is formed on the side surface of the side electrode 102a, thereby reducing the potential difference at the bottom surface position and the side surface position of the side electrode 102a to a certain extent and improving the withstand voltage ability of the inductor. The first peeling portion 1021a is arranged in a rectangular shape, and the maximum peeling width of the first peeling portion 1021a is smaller than the width of the side electrode 102a on the bottom surface of the molded body and larger than C. The second peeling portion 1022a is arranged in a rectangular shape, and the first peeling portion 1021a and the second peeling portion 1022a are connected at a bottom edge of the molded body.
[0036] Example 6 Please refer to Figure 11 , a third peeling portion 1021b is formed on the bottom electrode 102b. The third peeling portion 1021b is in an arc shape, and the peeling width of the third peeling portion 1021b is smaller than the width of the bottom electrode 102b and larger than C, thereby reducing the potential difference at the bottom surface position of the bottom electrode 102b to a certain extent and improving the withstand voltage ability of the inductor.
[0037] Example 7 Please refer to Figure 12 , a third peeling portion 1021b is formed on the bottom electrode 102b. The third peeling portion 1021b is in a rectangular shape, and the peeling width of the third peeling portion 1021b is smaller than the width of the bottom electrode 102b and larger than C, thereby reducing the potential difference at the bottom surface position of the bottom electrode 102b to a certain extent and improving the withstand voltage ability of the inductor.
[0038] Example 8 Please refer to Figure 13 , a third peeling portion 1021b is formed on the bottom electrode 102b. The third peeling portion 1021b is in a rectangular shape, and the peeling of the third peeling portion 1021b is smaller than the width of the bottom electrode 102b and larger than C, thereby reducing the potential difference at the bottom surface position of the bottom electrode 102b to a certain extent and improving the withstand voltage ability of the inductor.
[0039] In the present invention, a manufacturing method of an integrated surface mount inductor is also proposed, including the following steps: integrally molding the coil 104 and the granulated powder 101 to form a molded body, and the end of the coil 104 leaks out from the molded body; applying an insulating resin around the molded body, and then peeling the insulating resin by laser, and adjusting the electrode range through the electrode peeling position; then plating copper or applying a conductive glue at the electrode peeling position of the molded body, and plating Ni and Sn on the position where the copper is plated or the conductive glue is applied to form an external electrode to complete the manufacturing.
[0040] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.
[0041] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard 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. An integrally formed surface mount inductor, comprising a molded body integrally formed by a coil (104) and granulated powder (101), wherein an end of the coil (104) leaks out of the molded body, and an external electrode is formed on the outer side of the molded body, characterized in that: The side surface and / or bottom surface of the external electrode is formed with an electrode peeling position for changing the electrode range.
2. The one-piece surface mount inductor according to claim 1, characterized in that: The external electrode comprises a side electrode (102a), a first peeling portion (1021a) being formed on the bottom surface of the side electrode (102a) and / or a second peeling portion (1022a) being formed on the side surface of the side electrode (102a).
3. The one-piece surface mount inductor according to claim 2, characterized in that: The first peeling portion (1021a) and the second peeling portion (1022a) are arranged in an arc shape or a rectangular shape.
4. The one-piece surface mount inductor according to claim 2, characterized in that: The peeling width of the first peeling portion (1021a) is less than or equal to the width of the side electrode (102a) located on the bottom surface of the molded body.
5. The one-piece surface mount inductor according to claim 1, characterized in that: The external electrode comprises a bottom electrode (102b), and a third peeling portion (1021b) is formed on the bottom electrode (102b).
6. The one-piece surface mount inductor according to claim 5, characterized in that: The third peeling portion (1021b) is arranged in an arc shape or a rectangular shape.
7. The one-piece surface mount inductor according to claim 5, characterized in that: The stripping width of the third stripping portion (1021b) is less than or equal to the width of the bottom electrode (102b).
8. A method for manufacturing an integrally formed surface mount inductor according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: integrally molding a coil (104) and granulated powder (101) to form a molded body, wherein the end of the coil (104) leaks out of the molded body; applying insulating resin to the periphery of the molded body, then peeling off the insulating resin by laser, and adjusting the electrode range by the electrode peeling position; and then electroplating copper or applying conductive glue to the electrode peeling position of the molded body, and then plating Ni and Sn at the copper-plated or conductive glue-applied position to form an external electrode to complete the manufacturing.