Magnetic and inductive devices

Abstract

This disclosure provides a magnetic component and an inductive device. The magnetic component (100) includes a first magnetic core (1), a second magnetic core (2), and a printed circuit board (3). The first magnetic core (1) includes a first side post (11), a second side post (12), and a central post (13). The printed circuit board (3) has a plurality of through holes (31). The first side post (11) and the second side post (12) respectively abut against the second magnetic core (2) through the through holes (31), and the central post (13) is bonded to the second magnetic core (2) through the through holes (31). The magnetic component of this disclosure has good performance stability and space utilization.

Description

Technical Field

[0001] This disclosure relates to the field of manufacturing miniaturized, planar electronic components, and more specifically, to a magnetic component and an inductor. Background Technology

[0002] This section aims to provide background information relevant to understanding the various techniques described herein. As the title of this section implies, this is a discussion of related techniques that should in no way imply that they are necessarily prior art. Therefore, it should be understood that any statement in this section should be read in this context, rather than as an admission of any prior art.

[0003] Electronic products are now trending towards miniaturization and thinner designs. Transformers, as one of the key components in power electronic equipment, are also trending towards miniaturization and planarization.

[0004] Mounting two magnetic cores of a planar magnetic component onto different surfaces of a printed circuit board (PCB) is a crucial step in the PCB mounting process. Currently, a snap-fit ​​method is commonly used. Grooves matching standard-sized metal snap-fits are pressed into the surface of the planar magnetic component, and the two magnetic cores are secured by the engagement of the snap-fit ​​with the grooves. This installation method is manual, resulting in low production efficiency. Furthermore, because different types of magnetic components require different types of snap-fits, its versatility is poor, hindering the adoption of automated production.

[0005] In addition, there is also a method of directly applying glue to the double E type (EE type) magnetic core and then curing it by reflow soldering. However, in this case, there is an air gap at the matching joint surface of the EE type magnetic core, and the magnetic field leakage in the vicinity is relatively severe, which leads to eddy current loss on the coil and large fluctuations in the air gap caused by the glue application position. Utility Model Content

[0006] The purpose of this disclosure is to obtain a magnetic component with good performance stability and space utilization.

[0007] Furthermore, the purpose of this disclosure is to solve or at least alleviate one or more problems existing in the prior art.

[0008] This disclosure solves the above problems by providing a magnetic component and an inductive device. Specifically, according to one aspect of this disclosure, the following is provided:

[0009] A magnetic component, comprising a first magnetic core, a second magnetic core, and a printed circuit board, wherein the first magnetic core comprises a first side post, a second side post, and a central post, and the printed circuit board has a plurality of through holes, wherein the first side post and the second side post abut against the second magnetic core through the through holes, and the central post is bonded to the second magnetic core through the through holes.

[0010] Alternatively, according to one embodiment of this disclosure, the bonding is achieved by applying an adhesive, and the curing of the adhesive is achieved by means of the soldering temperature of the surface mount electronics on the printed circuit board.

[0011] Alternatively, according to one embodiment of this disclosure, the end face of the central post extends beyond or is flush with the surface of the printed circuit board facing the second magnetic core.

[0012] Alternatively, according to one embodiment of this disclosure, the second magnetic core is bonded to the printed circuit board.

[0013] Optionally, according to one embodiment of this disclosure, the adhesive is epoxy adhesive, and the welding is reflow soldering.

[0014] Alternatively, according to one embodiment of this disclosure, the bottom of the first magnetic core is spaced apart from the printed circuit board.

[0015] Optionally, according to one embodiment of this disclosure, the second magnetic core covers the through hole when viewed along the thickness direction of the magnetic element.

[0016] Optionally, according to one embodiment of this disclosure, when viewed along the length of the second magnetic core, the width of the central post is greater than the width of both the first and second side posts.

[0017] Optionally, according to one embodiment of this disclosure, when viewed along the length of the second magnetic core, the bonding positions between the second magnetic core and the printed circuit board are respectively located between the first side post and the middle post, and between the second side post and the middle post.

[0018] According to another aspect of this disclosure, an inductor is provided, wherein the inductor includes any of the magnetic elements described above. Attached Figure Description

[0019] Referring to the accompanying drawings, the above and other features of this disclosure will become apparent, wherein,

[0020] Figure 1 A schematic diagram of the assembly of a second magnetic core and a printed circuit board according to the present disclosure is shown; and

[0021] Figure 2 A schematic diagram of the structure of a magnetic component according to the present disclosure is shown. Detailed Implementation

[0022] It is readily understood that, based on the technical solutions of this disclosure, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of this disclosure. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solutions of this disclosure and should not be considered as the entirety of this disclosure or as limitations or restrictions on the technical solutions of this disclosure.

[0023] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive. Furthermore, the terms "first," "second," "third," and similar expressions are used for descriptive and distinguishing purposes only and should not be construed as indicating or implying the relative importance of the corresponding components.

[0024] Figure 1 A schematic diagram of the assembly of a second magnetic core and a printed circuit board according to the present disclosure is shown; and Figure 2 A schematic diagram of the structure of a magnetic component according to the present disclosure is shown.

[0025] The magnetic component 100 includes a first magnetic core 1, a second magnetic core 2, and a printed circuit board 3. The first magnetic core 1 includes a first side post 11, a second side post 12, and a central post 13. The printed circuit board 3 has a plurality of through holes 31. The first side post 11 and the second side post 12 abut against the second magnetic core 2 through the through holes 31, and the central post 13 is bonded to the second magnetic core 2 through the through holes 31.

[0026] It should be understood that this document uses an E-type magnetic core as an example and an I-type magnetic core as an example for illustration; however, this is not limiting. Those skilled in the art, based on the technical concepts and solutions of this disclosure, can apply the first or second magnetic core to magnetic cores of other shapes, such as both being E-type cores, or even irregularly shaped cores. Furthermore, the first and second magnetic cores can be separate components or parts of components. For example, if a magnetic core of a certain shape contains an E-type or I-type structure, then that structure can be considered an E-type or I-type core. In addition, the terms "E-type" and "I-type" in this document describe the corresponding core shapes; of course, the core only needs to generally resemble an E-type or I-type shape.

[0027] Feasibly, the first magnetic core includes a bottom 14, from which extend first and second side posts arranged on both sides, and a central post located between the first and second side posts and typically in the center. The entire first magnetic core can be constructed to be relatively thin, i.e., thin relative to its length and width, so as to be a relatively flat, planar electronic component. Similarly, the I-type structure is a generally thin-plate structure that extends straight or substantially straight. Furthermore, it should be understood that the printed circuit board itself has built-in laminated copper foil (copper busbars) forming windings, naturally providing a foundation for the magnetic circuit of the magnetic component. Therefore, winding operations are unnecessary; in previous winding techniques, steps such as insulation and frame support were often required, which can now be eliminated. Thus, this disclosure utilizes the characteristics of the printed circuit board itself, combined with the magnetic core, to form the magnetic component, resulting in high material utilization and cost-effectiveness. A reasonable adhesive application location (i.e., applying adhesive using the air gap between the central post and the second magnetic core) achieves a stable inductance control level.

[0028] This technical solution also features a special design where the two side posts of the first magnetic core abut against the second magnetic core, while the central post of the first magnetic core is bonded to the second magnetic core. Since a gap, or air gap, should naturally exist between the central post of the first magnetic core and the second magnetic core, this disclosure utilizes this air gap for bonding (e.g., applying adhesive within the gap), resulting in better performance stability and space utilization. The connection method of this solution, combined with the windings of the circuit board, forms a closed magnetic circuit, improving the magnetic efficiency of the magnetic components. The closed magnetic circuit reduces magnetic leakage, making the magnetic field more concentrated and improving the working performance of the magnetic components. Furthermore, the through-hole design on the circuit board provides positioning points for the assembly of the magnetic cores, simplifying the assembly process. This design also facilitates automated production, improves manufacturing efficiency, and overcomes the production consistency yield problems caused by semi-automatic or manual assembly. For example, three through-holes are used, respectively for the mating of the two side posts and the central post of the first magnetic core.

[0029] Compared to the dual-E core design, where the air gap is located between the two central pillars for energy storage, and the side pillars are bonded together, the adhesive used for bonding has a certain thickness that is difficult to control and subject to uncertainty. This thickness affects the size of the air gap between the side pillars, thus impacting inductance and magnetic saturation capability, potentially leading to poor performance. This design uses a first and second core in combination, with the central pillar of the first core bonded to the second core. This results in better performance stability and space utilization. Furthermore, the side pillars of the first core abut against the second core, and can be grounded without adhesive, eliminating the unstable air gap size issue common in dual-E core designs and ensuring consistent performance.

[0030] In some embodiments of this disclosure, the bonding is achieved by applying an adhesive, and the curing of the adhesive is achieved by means of the soldering temperature of the surface mount electronics on the printed circuit board 3.

[0031] In this design, the surface-mount electronic components can refer to the second magnetic core or the first magnetic core itself, or other surface-mount electronic components such as magnetic parts or inductors that need to be surface-mounted with the printed circuit board. Since the surface-mount electronic components are mounted on the printed circuit board using soldering, the high temperatures generated during this process can be used to cure the applied adhesive, achieving multiple functions in the soldering process. Furthermore, the adhesive curing does not occupy additional manufacturing time or steps, improving production efficiency, reducing production costs, and making it suitable for automated production, thus improving production consistency and stability.

[0032] In addition, the heat generated during the welding process is generally uniform and stable, which is conducive to the uniform curing of the adhesive, thereby ensuring the quality of the bonding and helping to improve the reliability and service life of the magnetic components.

[0033] Regarding the relative position of the first magnetic core and the circuit board, it is feasible for the end face of the central post 13 to extend beyond or be flush with the surface of the printed circuit board 3 facing the second magnetic core 2.

[0034] This technical solution essentially designs the bonding position or air gap position between the central post of the first magnetic core and the second magnetic core. It's understandable that the farther the air gap is from the circuit board windings, the smaller or even non-existent the turbulence loss, and the better the performance of the magnetic components. Therefore, those skilled in the art can determine the air gap position based on actual conditions and requirements, such as performance requirements, compactness requirements, and heat dissipation requirements.

[0035] On the other hand, this layout design can increase the stability of the magnetic component structure, resist external vibration and impact, and reduce the deformation and displacement of the magnetic component during operation, thereby improving the reliability and service life of the magnetic component.

[0036] Alternatively, the second magnetic core 2 can be bonded to the printed circuit board 3.

[0037] In this regard, compared to traditional mechanical fixing methods (such as screw fixing, clip fixing, etc.), adhesive bonding technology eliminates the need for additional fasteners and tools, simplifying the assembly process of the magnetic core and printed circuit board, improving production efficiency, and reducing production costs. Furthermore, adhesive bonding technology can also firmly fix the second magnetic core to the printed circuit board, preventing displacement or detachment under vibration or impact, reducing contact resistance and magnetic reluctance, thereby improving the structural stability and electromagnetic performance of the entire magnetic component. Adhesive bonding also typically has certain thermal conductivity, effectively conducting the heat generated by the second magnetic core during operation to the printed circuit board, and then dissipating it into the air through the heat dissipation structure on the printed circuit board (such as heat sinks, ventilation holes, etc.). This reduces the operating temperature of the magnetic core, improving its performance and lifespan. Finally, the shape of the second magnetic core and its adhesive fit with the circuit board also contribute to improved space utilization and the realization of a flattened overall magnetic component.

[0038] For a specific implementation of bonding and welding, an example is that the adhesive is epoxy adhesive and the welding is reflow soldering.

[0039] In this regard, epoxy adhesive possesses excellent bonding properties, firmly bonding the magnetic core and printed circuit board to form a stable mechanical connection. It can withstand significant tensile and shear forces, ensuring that the magnetic components will not loosen or detach under vibration or impact. After curing, epoxy adhesive also forms a hard, uniform, and consistent adhesive layer, guaranteeing the quality and performance of the magnetic components and protecting the bonding surfaces from corrosion and wear, further improving the reliability and durability of the bond. As mentioned earlier, epoxy adhesive also has certain thermal conductivity, effectively conducting the heat generated by the magnetic core during operation to the printed circuit board, and then dissipating it into the air through the heat dissipation structure on the printed circuit board.

[0040] Reflow soldering is a precise and automated soldering method that can complete the soldering of multiple points at once, ensuring the quality and consistency of the solder joints, reducing soldering defects and defect rates, and greatly improving production efficiency.

[0041] Finally, as mentioned earlier, the curing process of epoxy adhesive can be combined with the heating process of reflow soldering, eliminating the need for additional heating steps and simplifying the production process. Both methods are suitable for automated production lines, enabling efficient and stable mass production.

[0042] Combination Figure 2It can also be seen that the bottom 14 of the first magnetic core 1 is spaced apart from the printed circuit board 3. This design not only helps with heat dissipation but also reduces magnetic interference between the magnetic core and the printed circuit board, making the magnetic field more concentrated and thus improving the magnetic efficiency of the magnetic component. This spacing provides space for disassembly tools or operations when the first magnetic core needs to be disassembled. Furthermore, this non-contact design reduces mechanical stress between the first magnetic core and the circuit board, especially mechanical stress caused by thermal expansion during operation, thereby improving the reliability and service life of the magnetic component.

[0043] Alternatively, when viewed along the length direction X of the second magnetic core 2, the width of the central post 13 is greater than the widths of the first side post 11 and the second side post 12.

[0044] The length direction of the second magnetic core is illustrated in the accompanying drawings. The meaning of the length direction should be understood. For example, taking the cross-sections of the first and second magnetic cores (which represent the type of magnetic core, such as E-type or I-type) as a plane, the direction of the longer side of the second magnetic core is the length direction. The width direction of the central post of the first magnetic core is parallel to this length direction. Therefore, it can be understood that, as the core part of the magnetic core, an increase in the width of the central post means an increase in the cross-sectional area of ​​the magnetic core. With a constant magnetic flux, an increase in cross-sectional area can reduce the magnetic flux density, thereby reducing the magnetic reluctance of the magnetic core and allowing the magnetic flux to pass through the core more smoothly. This, in turn, can increase the permeability and inductance of the magnetic core, enhancing its magnetic properties. An increase in the width of the central post can also reduce the AC resistance of the inductor, reduce energy loss, and improve the frequency response characteristics of the inductor, enabling it to maintain stable performance over a wider frequency range. Furthermore, an increase in the width of the central post can increase the magnetic field strength of the inductor, thereby increasing its saturation current and improving the stability and reliability of the inductor in high-current applications. Finally, the increased width of the center column means a larger core volume, which provides more surface area for heat dissipation, reduces the operating temperature of the inductor, and improves its stability and lifespan in high-temperature environments.

[0045] During the assembly of the second magnetic core, viewed along the thickness direction of the magnetic component 100, the second magnetic core 2 covers the through hole 31.

[0046] Covering the through-hole means covering the two side posts of the first magnetic core; therefore, the bottom of the first magnetic core and the second magnetic core can be considered as part of the outer shell of the magnetic component. This shell design forms an electromagnetic shielding layer, effectively blocking interference from external electromagnetic fields. Furthermore, this design facilitates easier assembly of the first magnetic core and the second magnetic core via the through-hole.

[0047] For example, regarding the design of the bonding position of the second magnetic core, when viewed along the length direction X of the second magnetic core 2, the bonding positions of the second magnetic core 2 and the printed circuit board 3 are respectively located between the first side post 11 and the middle post 13, and between the second side post 12 and the middle post 13.

[0048] As can be seen from the bonding between the central post of the first magnetic core and the second magnetic core, this technical solution designs a three-segment bonding method for the second magnetic core, and the bonding positions are not at the two ends of the second magnetic core. This effectively disperses stress and improves the stability of the entire structure. This bonding method can make greater use of the length of the second magnetic core, resulting in a larger contact area and stronger heat dissipation. In some other embodiments, bonding positions can also be set at both ends of the second magnetic core for bonding to the circuit board, while no bonding positions are set within the side post of the first magnetic core.

[0049] The following is an exemplary description of the specific assembly method of the magnetic components disclosed herein.

[0050] In one optional assembly method, the assembly method includes: step S1: attaching the SMT chip onto the circuit board; step S2: applying adhesive to a first surface of the printed circuit board, the first surface being, for example, […]. Figure 1 The upper surface of the circuit board has a through hole for the first magnetic core to pass through; Step S3: The second magnetic core is mounted on the adhesive-coated circuit board surface, and the second magnetic core can completely cover the through hole reserved on the circuit board for the assembly of the first magnetic core; Step S4: The circuit board with the second magnetic core mounted is reflow soldered together with the electronic components on the board surface to make the second magnetic core bonded and cured to the circuit board; Step S5: The entire assembly is rotated 180 degrees, and a second application of adhesive is made at the joint surface of the second magnetic core and the first magnetic core; Step S6: The SMT chip is mounted on the circuit board; Step S7: The first magnetic core is mounted, passing through the through hole of the circuit board and mounted on the surface of the second magnetic core; Step S8: The first magnetic core is reflow soldered together with the electronic components on the circuit board surface to make the first magnetic core and the second magnetic core bonded and cured.

[0051] Through the assembly of the planar magnetic core scheme of the circuit board through the above steps, automated production was achieved, efficiency was improved, and the reasonable glue application position (i.e., using the air gap between the central column and the second magnetic core for glue application) achieved a stable inductance control level.

[0052] In addition, during the mounting process of the first magnetic core and the second magnetic core in step S7, a force can be applied to the bottom of the first magnetic core in the direction of the second magnetic core, so that the adhesive 4 can perform its bonding function more quickly.

[0053] This disclosure also relates to an inductor device, wherein the inductor device includes any of the above-described magnetic components 100.

[0054] Therefore, the inductive device disclosed herein can inherit various implementation methods and corresponding technical effects of magnetic components, which will not be elaborated further here. However, it should be mentioned that the inductive device in this article should be interpreted broadly, including various inductive devices that can perform functions such as power conversion, power supply, and electromagnetic coupling, such as transformers.

[0055] It should be understood that all the above preferred embodiments are exemplary and not restrictive, and various modifications or variations made by those skilled in the art to the specific embodiments described above under the concept of this disclosure should be within the legal protection scope of this disclosure.

Claims

1. A magnetic component (100), characterized in that, The magnetic component (100) includes a first magnetic core (1), a second magnetic core (2), and a printed circuit board (3). The first magnetic core (1) includes a first side post (11), a second side post (12), and a central post (13). The printed circuit board (3) has several through holes (31). The first side post (11) and the second side post (12) abut against the second magnetic core (2) through the through holes (31), respectively. The central post (13) is bonded to the second magnetic core (2) through the through holes (31). The first magnetic core is an E-type magnetic core, and the second magnetic core is an I-type magnetic core. The end face of the central post (13) extends beyond or is flush with the surface of the printed circuit board (3) facing the second magnetic core (2).

2. The magnetic component (100) according to claim 1, characterized in that, The bonding is achieved by applying adhesive, and the curing of the adhesive is achieved by means of the soldering temperature of the surface mount electronics on the printed circuit board (3).

3. The magnetic component (100) according to claim 1, characterized in that, The second magnetic core (2) is bonded to the printed circuit board (3).

4. The magnetic component (100) according to claim 2, characterized in that, The adhesive is epoxy adhesive, and the welding is reflow soldering.

5. The magnetic component (100) according to claim 1, characterized in that, The bottom (14) of the first magnetic core (1) is spaced apart from the printed circuit board (3).

6. The magnetic component (100) according to claim 1, characterized in that, Viewed along the thickness direction of the magnetic component (100), the second magnetic core (2) covers the through hole (31).

7. The magnetic component (100) according to claim 1, characterized in that, Looking along the length of the second magnetic core (2), the width of the central column (13) is greater than the width of the first side column (11) and the width of the second side column (12).

8. The magnetic component (100) according to claim 3, characterized in that, Looking along the length of the second magnetic core (2), the bonding positions of the second magnetic core (2) and the printed circuit board (3) are respectively located between the first side post (11) and the middle post (13), and between the second side post (12) and the middle post (13).

9. An inductor device, characterized in that, The inductor includes a magnetic element (100) according to any one of claims 1 to 8.

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