Magnetic shielding inductor and manufacturing method thereof

Abstract

The invention relates to a magnetic shielding inductor and a manufacturing method thereof, and the manufacturing method of the magnetic shielding inductor comprises the steps: putting a prefabricated hollow coil into a magnetic body, enabling a coil terminal of the hollow coil to be exposed on a terminal surface of the magnetic body, and smearing a shielding coating on a shielding surface of the magnetic body to form a shielding coating; the magnetic shielding inductor comprises a magnetic body, a hollow coil and a shielding coating, the magnetic body is provided with a shielding face and a terminal face, a part of coil terminals of the hollow coil are exposed out of the terminal face of the magnetic body, and the shielding face is coated with the shielding coating. According to the integrally-formed inductor and the manufacturing method thereof, the shielding coating is coated on the shielding surface of the magnetic body, so that the shielding coating can be generated on the shielding surface of the inductor, the purpose of improving the magnetic shielding effect is achieved, and compared with an existing mode that the magnetic shielding effect is achieved by winding copper foil and the like, the manufacturing cost is reduced. The mode of forming the shielding coating in a printing mode is low in cost, and the manufacturing process is simple.

Description

Technical Field

[0001] The present application relates to the technical field of magnetic shielding inductors and methods for manufacturing the same, and in particular to magnetic shielding inductors and methods for manufacturing the same. Background Art

[0002] Inductors, also known as inductor coils, sometimes also called reactors or chokes, are one of the basic components of electronic circuits and are widely used in signal processing, noise filtering, power generation, power transmission and other technical fields. Taking digital power amplifiers as an example, their miniaturization and integration are getting higher and higher. For inductors used in digital power amplifiers, the external magnetic field will interfere with the magnetic field generated by the inductor itself, affecting its function. On the other hand, the electromagnetic radiation generated by the inductor to the outside must be shielded. Therefore, such inductors need to be magnetically shielded.

[0003] The current one-piece molded inductors have a slightly better magnetic shielding effect, but because most of the one-piece molded inductors are directly installed on the motherboard of the electronic components, they are still easily affected by the magnetic fields of other electronic components, which reduces the use effect of the inductor and easily affects the service life of the one-piece molded inductor. Summary of the invention

[0004] Based on this, it is necessary to provide a magnetic shielding inductor and a manufacturing method thereof to further optimize the magnetic shielding effect of the above-mentioned one-piece molded inductor.

[0005] According to one aspect of the present application, a method for manufacturing a magnetic shielded inductor is provided, comprising:

[0006] The prefabricated hollow coil is installed into the magnetic body, and the coil terminal of the hollow coil is exposed on the terminal surface of the magnetic body;

[0007] The shielding paint is applied to the shielding surface of the magnetic body to form a shielding coating.

[0008] In one embodiment, the shielding surface is a side surface of the magnetic body that is opposite to the terminal surface.

[0009] In one of the embodiments, the method for manufacturing the magnetic shielded inductor further includes: preparing a shielding coating;

[0010] The preparation of the shielding coating comprises:

[0011] Obtain copper slurry;

[0012] Get metal fillers and flux;

[0013] Add metal filler and flux into the copper paste and stir well.

[0014] In one embodiment, the step of applying the shielding coating to the shielding surface of the magnetic body to form a shielding coating comprises:

[0015] Apply the shielding paint to the shielding surface of the magnetic body;

[0016] The shielding paint on the shielding surface is cured at a temperature of 140° C. to 160° C. for 30 minutes to form a shielding coating.

[0017] In one embodiment, applying the shielding coating on the shielding surface of the magnetic body further comprises:

[0018] The thickness of the shielding paint applied on the magnetic body is controlled to be greater than or equal to 0.05 mm and less than or equal to 0.1 mm.

[0019] According to another aspect of the present application, a magnetic shielding inductor is provided, which is manufactured by using the method for manufacturing a magnetic shielding inductor as described in any one of the above embodiments, comprising:

[0020] A magnetic body having a shielding surface and a terminal surface;

[0021] The hollow coil comprises a coil body and two coil terminals, wherein the coil body is buried inside the magnetic body, the two coil terminals are respectively arranged on two connecting ends of the coil body, and a part of the coil terminals is exposed on the terminal surface of the magnetic body;

[0022] The shielding coating is coated on the shielding surface.

[0023] In one of the embodiments, the shielding surface and the terminal surface are respectively arranged on two side surfaces of the magnetic body that are opposite to each other along the axial direction of the air-core coil.

[0024] In one embodiment, the orthographic projection area of ​​the shielding coating on the magnetic body is equal to the orthographic projection area of ​​the shielding surface on the magnetic body.

[0025] In one embodiment, along the axial direction of the hollow coil, the thickness of the shielding coating is greater than or equal to 0.05 mm and less than or equal to 0.1 mm.

[0026] In one of the embodiments, the shielding coating is formed by applying a shielding paint, and the shielding paint includes copper paste, metal filler and flux.

[0027] The above-mentioned one-piece molded inductor and its manufacturing method, by applying shielding paint on the shielding surface of the magnetic body, a shielding coating can be generated on the shielding surface of the inductor to improve the magnetic shielding effect. Compared with the existing method of achieving magnetic shielding effect by winding copper foil, the method of forming the shielding coating by printing in the present application is lower in cost and the process is also simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic flow chart of a method for manufacturing a magnetically shielded inductor according to some embodiments of the present application.

[0029] Figure 2 This is a schematic structural diagram of a magnetically shielded inductor according to some embodiments of the present application.

[0030] Figure 3 This is a schematic diagram of the structure of the magnetic shielded inductor after the shielding coating and the magnetic body are separated in some embodiments of the present application.

[0031] Reference numerals:

[0032] 1. Magnetic body; 11. Shielding surface; 12. Terminal surface;

[0033] 2. hollow coil; 21. coil body; 22. coil terminal;

[0034] 3. Shielding coating. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0036] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0037] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0038] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0039] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0041] Inductors, also known as inductor coils, sometimes also called reactors or chokes, are one of the basic components of electronic circuits and are widely used in technical fields such as signal processing, noise filtering, power generation, and power transmission. Taking digital power amplifiers as an example, their miniaturization and integration are becoming increasingly high. For inductors used in digital power amplifiers, the external magnetic field will interfere with the magnetic field generated by the inductor itself, affecting its function. On the other hand, the electromagnetic radiation generated by the inductor to the outside must be shielded. Therefore, such inductors need to be magnetically shielded. Compared with traditional assembled inductors, one-piece molded inductors (molded inductors) have low impedance, low parasitic capacitance, small size, large current, and can still maintain excellent temperature rise current and saturation current characteristics in high frequency and high temperature environments. They are widely used in consumer, industrial, and automotive electronic devices.

[0042] Compared with inductor components, traditional inductors, such as NR, CD and other winding inductors, use magnetic glue sealing, and have poor magnetic shielding effect. Although the current one-piece molded inductors have a slightly better magnetic shielding effect, since most of the one-piece molded inductors are directly installed on the motherboard of the electronic components, they are still easily affected by the magnetic field of other electronic components, which reduces the use effect of the inductor and easily affects the service life of the one-piece molded inductor. In addition, in the prior art, most of them adopt a single-layer soft magnetic material shielding method, such as winding copper foil on the outside of the inductor to achieve magnetic shielding, and the shielding effect is general. In addition, affected by the winding process, the reliability of its shielding is not high.

[0043] In summary, the present application generates a shielding coating on the shielding surface of the inductor by printing, which can not only improve the magnetic shielding effect, but also, compared with the existing method of achieving the magnetic shielding effect by winding copper foil, the present application forms a shielding coating by printing, which has lower cost and a simpler process.

[0044] See also Figure 1 and Figure 2 An embodiment of the present application provides a method for manufacturing a magnetic shielding inductor, characterized by comprising:

[0045] The prefabricated hollow coil 2 is loaded into the magnetic body 1, and the coil terminal 22 of the hollow coil 2 is exposed on the terminal surface 12 of the magnetic body 1. Specifically, the wound hollow coil 2 and the magnetic metal powder are pressed by pressure to form an integrally formed inductor, and the material covering the coil end is removed by grinding peeling, chemical etching peeling or laser peeling to expose the coil terminal 22 of the hollow coil 2.

[0046] The shielding paint is applied to the shielding surface 11 of the magnetic body 1 to form a shielding coating 3 to enhance the magnetic shielding effect.

[0047] Specifically, the shielding surface 11 and the terminal surface 12 are respectively located on different side surfaces of the magnetic body 1 to ensure that the provision of the shielding coating 3 does not affect the installation between the inductor and the electronic component.

[0048] More specifically, in one embodiment of the present application, the shielding surface 11 and the terminal surface 12 are respectively arranged on two opposite side surfaces of the magnetic body 1. In another embodiment of the present application, a plurality of shielding surfaces 11 are provided, and the plurality of shielding surfaces 11 are respectively located on different side surfaces from the terminal surface 12.

[0049] It is understandable that the larger the coating area of ​​the shielding coating 3, the better its shielding effect, but the cost will also increase. This application uses an electromagnetic shielding tester to test the shielding effectiveness, uses an electromagnetic compatibility (EMC) test device to test the wave impedance, absorption loss and reflection loss, uses an electromagnetic wave propagation characteristic test device to test the skin depth, and uses a near magnetic field measurement system to measure the leakage flux. It is found that when the shielding coating 3 is only applied on the shielding surface 11 that is opposite to the terminal surface 12 of the magnetic body 1, the inductor can achieve the specified shielding effect. When the shielding coating 3 is applied on multiple shielding surfaces 11 of the magnetic body 1, the inductor can achieve the specified shielding effect, but the cost required to produce each inductor is relatively high. Therefore, this application can simultaneously ensure that the inductor has a better shielding effect and a lower cost by applying the shielding coating 3 only on the shielding surface 11 that is opposite to the terminal surface 12 of the magnetic body 1.

[0050] The manufacturing method of the one-piece molded inductor of the present application applies a shielding coating on the shielding surface 11 of the magnetic body 1, so that a shielding coating 3 can be generated on the shielding surface 11 of the inductor to improve the magnetic shielding effect. Compared with the existing method of achieving the magnetic shielding effect by winding copper foil, the method of forming the shielding coating 3 by printing in the present application is lower in cost and the process is also simpler.

[0051] In one embodiment, the method for manufacturing a magnetic shielded inductor further includes: preparing a shielding coating. The preparing the shielding coating includes:

[0052] First, copper paste is obtained, and then metal filler and flux are obtained, and the addition ratio between copper paste, metal filler and flux is 99:1.

[0053] Add metal filler and soldering flux into the copper paste and stir evenly. By making the shielding coating include copper paste, metal filler and soldering flux, the adhesion of the copper paste to the substrate after curing can be effectively improved, thereby ensuring the stability of the shielding coating 3 on the shielding surface 11.

[0054] Wherein, the metal filler and the soldering flux are one or more of γ-(2,3-epoxypropoxy)propyltrimethoxysilane, methylimidazolyltriethoxysiloxane or aminopropyltrimethoxysilane.

[0055] In addition, in addition to copper paste, the present application may also use aluminum paste or silver paste.

[0056] In one embodiment, a shielding coating is applied to the shielding surface 11 of the magnetic body 1 to form a shielding coating 3, including:

[0057] The shielding paint is applied to the shielding surface 11 of the magnetic body 1 , and the shielding paint on the shielding surface 11 is cured at a temperature of 140° C. to 160° C. for 30 minutes to form a shielding coating 3 .

[0058] Specifically, the shielding coating is applied to the shielding surface 11 of the magnetic body 1 of the shielding coating 3, and the shielding coating on the shielding surface 11 is cured for 30 minutes at a temperature range of 140°C-160°C to form a shielding coating 3. According to tests, when the curing temperature is less than 140°C for 30 minutes, the curing effect is incomplete. When the curing temperature is greater than 160°C for 30 minutes, the shielding coating oxidizes too quickly. Therefore, the present application uses a curing temperature in the range of 140°C-160°C for 30 minutes to avoid excessive oxidation while ensuring that the shielding coating 3 has a better curing effect.

[0059] In one embodiment, the shielding coating is applied to the shielding surface 11 of the magnetic body 1, and further includes:

[0060] The thickness of the shielding paint applied on the magnetic body 1 is controlled to be greater than or equal to 0.05 mm and less than or equal to 0.1 mm, so as to ensure that the inductor has a good shielding effect and a low cost at the same time.

[0061] More specifically, when the shielding coating is applied to the shielding surface 11 of the magnetic body 1 of the shielding coating 3, the thickness of the shielding coating 3 is controlled to be greater than or equal to 0.05 mm and less than or equal to 0.1 mm. It can be understood that the greater the thickness of the shielding coating 3, the better the shielding effect, but the cost will also increase accordingly. According to tests, when the thickness of the shielding coating 3 is less than 0.05 mm, the inductor cannot achieve the specified shielding effect. When the thickness of the shielding coating 3 is greater than 0.1 mm, the inductor can achieve the specified shielding effect, but the cost required to produce each inductor is relatively high. Therefore, the present application can simultaneously ensure that the inductor has a good shielding effect and a low cost by making the thickness of the shielding coating 3 greater than or equal to 0.05 mm and less than or equal to 0.1 mm.

[0062] See also Figure 2 and Figure 3An embodiment of the present application further provides a magnetic shielding inductor, which is manufactured using the manufacturing method of a magnetic shielding inductor as described in any of the above embodiments, and includes a magnetic body 1, a hollow coil 2 and a shielding coating 3.

[0063] The magnetic body 1 is a high-density sintered magnetic core made of soft magnetic material. The hollow coil 2 is a coil made by pair winding, vertical winding, flying fork winding or external winding. The shielding coating 3 is arranged on the magnetic body 1 to improve the shielding effect of the inductor.

[0064] In the specific configuration, the magnetic body 1 has a shielding surface 11 and a terminal surface 12. The hollow coil 2 includes a coil body 21 and two coil terminals 22, the coil body 21 is buried inside the magnetic body 1, the two coil terminals 22 are respectively arranged on the two connecting ends of the coil body 21, and part of the coil terminals 22 are exposed on the terminal surface 12 of the magnetic body 1.

[0065] Specifically, the hollow coil 2 is wound by a flat wire, the middle part of the hollow coil 2 is buried inside the magnetic body 1, and the flat wires at both ends of the hollow coil 2 pass through the magnetic body 1 and are bent and attached to the side of the magnetic body 1. The flat wire bent and attached to the side of the magnetic body 1 is the coil terminal 22 exposed on the terminal surface 12 of the magnetic body 1.

[0066] The shielding coating 3 is coated on the shielding surface 11 to improve the magnetic shielding effect. It can be understood that the shielding surface 11 and the terminal surface 12 are respectively located on different sides of the magnetic body 1 to ensure that the setting of the shielding coating 3 does not affect the installation between the inductor and the electronic component.

[0067] Specifically, in one embodiment of the present application, the shielding surface 11 and the terminal surface 12 are respectively arranged on two opposite sides of the magnetic body 1. In another embodiment of the present application, a plurality of shielding surfaces 11 are provided, and the plurality of shielding surfaces 11 are respectively located on sides different from the terminal surface 12.

[0068] It is understandable that the larger the coating area of ​​the shielding coating 3, the better its shielding effect, but the cost will also increase. This application uses an electromagnetic shielding tester to test the shielding effectiveness, uses an electromagnetic compatibility (EMC) test device to test the wave impedance, absorption loss and reflection loss, uses an electromagnetic wave propagation characteristic test device to test the skin depth, and uses a near magnetic field measurement system to measure the leakage flux. It is found that when the shielding coating 3 is only applied on the shielding surface 11 that is opposite to the terminal surface 12 of the magnetic body 1, the inductor can achieve the specified shielding effect. When the shielding coating 3 is applied on multiple shielding surfaces 11 of the magnetic body 1, the inductor can achieve the specified shielding effect, but the cost required to produce each inductor is relatively high. Therefore, this application can simultaneously ensure that the inductor has a better shielding effect and a lower cost by applying the shielding coating 3 only on the shielding surface 11 that is opposite to the terminal surface 12 of the magnetic body 1.

[0069] In summary, the one-piece molded inductor of the present application, by applying shielding paint on the shielding surface 11 of the magnetic body 1, can generate a shielding coating 3 on the shielding surface 11 of the inductor, so as to achieve the purpose of improving the magnetic shielding effect. Compared with the existing method of achieving magnetic shielding effect by winding copper foil, the method of forming the shielding coating 3 by printing in the present application is lower in cost and the process is also simpler.

[0070] In one embodiment, the orthographic projection area of ​​the shielding coating 3 on the magnetic body 1 is equal to the orthographic projection area of ​​the shielding surface 11 on the magnetic body 1. This coating area can not only ensure the shielding effect, but also make the coating process of the shielding coating 3 simpler. That is, by making the orthographic projection area of ​​the shielding coating 3 on the magnetic body 1 equal to the orthographic projection area of ​​the shielding surface 11 on the magnetic body 1, it is possible to ensure that the inductor has a good shielding effect and a low cost at the same time, and also effectively ensure the process effect of the produced inductor.

[0071] In one embodiment, the thickness of the shielding coating 3 is greater than or equal to 0.05 mm and less than or equal to 0.1 mm along the axial direction of the hollow coil 2. It can be understood that the thicker the shielding coating 3 is, the better the shielding effect is, but the cost will also increase accordingly.

[0072] This application uses an electromagnetic shielding tester to test the shielding effectiveness, uses an electromagnetic compatibility (EMC) test device to test the wave impedance, absorption loss and reflection loss, uses an electromagnetic wave propagation characteristic test device to test the skin depth, and uses a near magnetic field measurement system to measure the leakage flux. It is found that when the thickness of the shielding coating 3 is between 0.05mm and 0.1mm, the inductor can achieve the specified shielding effect. When the thickness of the shielding coating 3 is less than 0.05mm, the inductor cannot achieve the specified shielding effect. When the thickness of the shielding coating 3 is greater than 0.1mm, the inductor can achieve the specified shielding effect, but the cost of producing each inductor is relatively high. Therefore, this application can ensure that the inductor has a good shielding effect and a low cost at the same time by making the thickness of the shielding coating 3 greater than or equal to 0.05mm and less than or equal to 0.1mm.

[0073] In one embodiment, the shielding coating 3 is formed by applying a shielding coating, and the shielding coating includes copper paste, metal filler and soldering flux. By making the shielding coating 3 include copper paste, metal filler and soldering flux, the adhesion of the copper paste to the substrate after curing can be effectively improved, thereby ensuring the stability of the shielding coating 3 on the magnetic body 1.

[0074] It is understandable that the metal filler is a special adhesive that is suitable for repairing defects in metal castings such as iron, steel, copper, and aluminum. Because it has strong adhesion and hardness, it can form a hard, wear-resistant, and corrosion-resistant protective layer on the metal surface. Flux is a chemical used in the welding process to remove the oxide layer on the metal surface, provide better contact performance, and help the melting and diffusion of solder and welding materials. The present application can effectively improve the adhesion of the copper paste to the substrate after curing by making the shielding coating include copper paste, metal filler, and flux, thereby ensuring the stability of the shielding coating on the magnetic body 1.

[0075] Specifically, the metal filler and the soldering flux are one or more of γ-(2,3-epoxypropyloxy)propyltrimethoxysilane, methylimidazolyltriethoxysiloxane or aminopropyltrimethoxysilane.

[0076] In summary, the present application generates a shielding coating on the shielding surface of the magnetic body 1 by printing, which can not only improve the magnetic shielding effect of the inductor, but also, compared with the existing method of achieving the magnetic shielding effect by winding copper foil, the present application forms the shielding coating by printing, which has lower cost and simpler process.

[0077] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A method for manufacturing a magnetic shielded inductor, characterized in that: include: The prefabricated hollow coil is installed into the magnetic body, and the coil terminal of the hollow coil is exposed on the terminal surface of the magnetic body; The shielding paint is applied to the shielding surface of the magnetic body to form a shielding coating.

2. The method for manufacturing a magnetic shielded inductor according to claim 1, wherein: The shielding surface is a side surface of the magnetic body that is away from the terminal surface.

3. The method for manufacturing a magnetic shielded inductor according to claim 1, wherein: The method for manufacturing the magnetic shielding inductor further comprises: preparing a shielding coating; The preparation of the shielding coating comprises: Obtain copper slurry; Get metal fillers and flux; Add metal filler and flux into the copper paste and stir well.

4. The method for manufacturing a magnetic shielded inductor according to claim 1, wherein: The method of applying the shielding coating to the shielding surface of the magnetic body to form a shielding coating comprises: Apply the shielding paint to the shielding surface of the magnetic body; The shielding paint on the shielding surface is cured at a temperature of 140° C. to 160° C. for 30 minutes to form a shielding coating.

5. The method for manufacturing a magnetic shielded inductor according to claim 1, wherein: The step of applying the shielding coating to the shielding surface of the magnetic body also includes: The thickness of the shielding paint applied on the magnetic body is controlled to be greater than or equal to 0.05 mm and less than or equal to 0.1 mm.

6. A magnetically shielded inductor, characterized in that: The magnetic shielding inductor is manufactured by the manufacturing method of any one of claims 1 to 5, characterized in that it comprises: A magnetic body having a shielding surface and a terminal surface; The hollow coil comprises a coil body and two coil terminals, wherein the coil body is buried inside the magnetic body, the two coil terminals are respectively arranged on two connecting ends of the coil body, and a part of the coil terminals is exposed on the terminal surface of the magnetic body; The shielding coating is coated on the shielding surface.

7. The magnetically shielded inductor according to claim 6, characterized in that: Along the axial direction of the air-core coil, the shielding surface and the terminal surface are respectively arranged on two opposite side surfaces of the magnetic body.

8. The magnetically shielded inductor according to claim 6, characterized in that: The orthographic projection area of ​​the shielding coating on the magnetic body is equal to the orthographic projection area of ​​the shielding surface on the magnetic body.

9. The magnetically shielded inductor according to claim 6, characterized in that: Along the axial direction of the hollow coil, the thickness of the shielding coating is greater than or equal to 0.05 mm and less than or equal to 0.1 mm.

10. The magnetically shielded inductor according to claim 6, wherein: The shielding coating is formed by applying a shielding paint, and the shielding paint includes copper paste, metal filler and soldering flux.

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