Vertical integrated inductor

Abstract

The application discloses a vertical integrally-formed inductor, and relates to the technical field of inductors, which comprises a shielding shell, a magnetic core column arranged in the shielding shell, a prefabricated support assembly sleeved outside the magnetic core column, a spiral coil wound on the prefabricated support assembly, and an integrated packaging layer filled in the shielding shell and covering the prefabricated support assembly, the coil and the magnetic core column to form an integrated structure; wherein the prefabricated support assembly comprises a spiral segment support and a lead support, the spiral segment support is in a cylindrical structure, a continuous spiral groove is formed in the outer wall of the spiral segment support, the cross section of the continuous spiral groove is a combination of a semicircular arc edge and a straight edge, and the angle between the line connecting the two endpoints of the semicircular arc edge and the horizontal line is an acute angle. Through the innovative structure design, the precise positioning and locking system and the optimization of materials and processes, the electrical performance consistency, the structural reliability, the production yield and the long-term stability of the vertical integrally-formed inductor are comprehensively improved.

Description

Technical Field

[0001] This invention relates to the field of inductor technology, specifically to a vertical, one-piece molded inductor. Background Technology

[0002] Molded inductors, as a key electronic component, are widely used in various space-constrained and high-performance power modules, such as servers, communication equipment, and new energy vehicle electronic control systems, due to their advantages such as small size, high power density, and good electromagnetic shielding. Traditional vertical molded inductors typically embed the coil directly into magnetic powder and then thermo-press it to form a structurally integrated package.

[0003] However, existing technologies still face several challenges in practical manufacturing and application. Firstly, during the thermoforming process, the encapsulation material (a mixture of magnetic powder and resin) flows and solidifies under high temperature and pressure, generating significant fluid pressure and mechanical stress on the pre-placed coil. If the coil lacks sufficiently robust internal support, it is highly susceptible to radial displacement, axial compression, or even overall deformation, leading to changes in turn spacing, coil damage, or misalignment with the magnetic core. These problems directly cause inductance drift, increased losses, and a decreased quality factor, severely impacting the inductor's electrical performance and long-term reliability.

[0004] Secondly, to fix the coil, existing technologies often use a structure with pre-set grooves in the support component, but the cross-section of the groove is mostly a simple semi-circular or rectangular shape. Semi-circular grooves have limited ability to wrap the coil and are difficult to effectively resist the pressure from the top of the encapsulation material; rectangular grooves are prone to forming dead corners for powder filling at the corners, resulting in uneven local support of the coil or insufficient encapsulation density, which also affects performance stability.

[0005] Furthermore, if the coil leads lack independent and reliable fixing and lead-out paths, the coil's spiral section is easily pulled under the stress of packaging or the mechanical stress of subsequent circuit board installation, causing micro-deformation or loosening of connection points, posing a potential risk of failure. Summary of the Invention

[0006] The purpose of this invention is to provide a vertically molded inductor to solve the problems mentioned in the background art.

[0007] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: The present invention provides a vertical integral molded inductor, comprising a shielding shell, a magnetic core column disposed within the shielding shell, a prefabricated support assembly sleeved on the outside of the magnetic core column, a spiral coil wound around the prefabricated support assembly, and an integral encapsulation layer filling the interior of the shielding shell and covering the prefabricated support assembly, the coil and the magnetic core column to form an integrated structure. The prefabricated support assembly includes a spiral segment support and a lead wire support. The spiral segment support is a cylindrical structure with a continuous spiral groove on its outer wall. The cross-section of the continuous spiral groove is a combination of a semi-circular arc edge and a straight edge. The angle between the line connecting the two endpoints of the semi-circular arc edge and the horizontal line is an acute angle. The straight edge is perpendicular to the line connecting the two endpoints of the semi-circular arc edge and extends radially upward along the spiral segment support. The top of the lead support is provided with a lead groove corresponding to the spiral coil. The lead segment of the spiral coil is inserted into the lead groove and extends along the lead groove to the outside of the shielding housing.

[0008] Furthermore, the shielding housing includes an outer shell with an open top and a cover that can be detachably installed on the top of the outer shell.

[0009] Furthermore, the lead support includes a first bent plate-shaped support corresponding to the upper lead of the coil, and a second bent plate-shaped support corresponding to the lower lead of the coil; Both the first and second bent plate-shaped supports have sides that are tightly attached to the spiral section support. The second plate-shaped support extends into the continuous spiral groove to form a locking part. The locking part and the semi-circular arc edge of the continuous spiral groove form a groove, which together enclose a closed circular space that is adapted to the diameter of the spiral coil. The lead groove includes a first horizontal lead groove formed on the top of the first plate-shaped support portion and a second horizontal lead groove formed on the second plate-shaped support portion.

[0010] Furthermore, the first bent plate-shaped support includes a first plate-shaped portion perpendicular to the tangential direction of the spiral segment support and a second plate-shaped portion parallel to the side wall of the shielding shell lead wire. The second bent plate-shaped support has the same shape as the first bent plate-shaped support and is symmetrically arranged with the first bent plate-shaped support. The second plate-shaped portion of the second bent plate-shaped support is fixedly connected to the opposite end of the second plate-shaped portion of the first bent plate-shaped support. The second plate-shaped part of the second bent plate-shaped support is provided with an upper connecting terminal at the end position of the upper lead wire, and a lower connecting terminal is provided on the second plate-shaped part of the second bent plate-shaped support at the end position of the lower lead wire. A through groove is provided on the lead wire leading side wall of the shielding shell at the positions of the upper and lower connecting terminals. The second plate-shaped part of the second bent plate-shaped support is in close contact with the lead wire leading side wall of the shielding shell. The bottom of the magnetic core column is provided with a locking groove, and the bottom of the shielding shell is provided with a locking component that matches the locking groove.

[0011] Furthermore, the angle between the line connecting the two endpoints of the semicircular arc and the horizontal line is 30°-60°.

[0012] Furthermore, the spiral segment support is made of an insulating high-temperature resistant material, which is selected from one or more of PBT, PA66, epoxy resin or LCP.

[0013] Furthermore, the lead wire support and the spiral segment support are made of the same material as the integral encapsulation layer.

[0014] Furthermore, the integrated encapsulation layer is made of a magnetic composite encapsulation material; the magnetic composite encapsulation material includes an epoxy resin matrix and magnetic particles dispersed therein.

[0015] Furthermore, the magnetic particles are selected from one or more of iron powder, carbonyl iron, iron-silicon-aluminum, or amorphous alloy powder.

[0016] Compared with existing technologies, one or more of the above technical solutions have the following beneficial effects: 1. The unique spiral groove cross-section design on the spiral segment support of this invention forms a close fit and support for the bottom of the coil at the semi-circular arc edge, effectively limiting its downward and inward displacement; the flared structure formed by the straight edge optimizes the filling flow of the encapsulation powder, ensuring dense filling around the coil. These two elements work synergistically to provide stable radial and axial support for the coil during thermoforming, greatly reducing the risk of coil displacement, deformation, or damage, and ensuring the stability of the inductance value and the structural reliability of the product.

[0017] 2. This invention provides a dedicated channel for laying and fixing the coil leads through an independent lead support and its lead groove design. This design effectively avoids external forces causing tensile deformation of the helical section through the leads during packaging or installation, thereby ensuring the long-term mechanical stability and conductive reliability of the electrical connection.

[0018] 3. The lead wire support of the present invention achieves mechanical locking of the coil end by embedding its locking part into the uppermost groove of the spiral section support, thus preventing it from loosening in subsequent processes.

[0019] 4. The connection terminals integrated on the lead support of this invention, in conjunction with the through slots on the side wall of the housing, achieve precise positioning of the component in the XY plane inside the housing; while the locking structure between the bottom of the magnetic core column and the bottom of the housing achieves vertical (Z-direction) positioning. These multi-level positioning structures together form a comprehensive mechanical interlocking system, achieving complete constraint on all internal components (prefabricated support components, coils, and magnetic cores) in all degrees of freedom before packaging. This ensures the consistency of the relative positions of each component and the accuracy of assembly repeatability, improving product consistency and yield.

[0020] 5. The prefabricated support assembly of the present invention adopts a modular design in which the helical segment support and the lead wire support can be separated, which makes the coil winding operation space larger and makes it easier to realize automated precision winding, thereby improving production flexibility and efficiency; while the lead wire support and the helical segment support achieve screwless pre-fixation and self-positioning through the locking part, simplifying the assembly steps.

[0021] In summary, this invention comprehensively improves the electrical performance consistency, structural reliability, production yield, and long-term stability of vertical integral molded inductors through innovative structural design, precise positioning and locking system, and optimization of materials and processes.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0023] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention after the cover is removed; Figure 3 This is a cross-sectional structural schematic diagram of the spiral segment support member of the present invention; Figure 4 yes Figure 3 A schematic diagram of the partial structure at point A; Figure 5 This is a schematic diagram of the prefabricated support assembly and coil structure of the present invention; Figure 6 This is a schematic diagram of the lead wire support structure of the present invention; Figure 7 This is a schematic diagram of the internal structure of the outer shell of the present invention; Figure 8 This is a schematic diagram of the locking groove structure of the present invention.

[0025] In the picture: 1-Shielding shell; 11-Outer shell; 12-Cover; 13-Shielding shell lead wire exit sidewall; 131-Through groove; 14-Clamping component; 2-Magnetic core post; 21-Clamping groove; 3-Prefabricated support assembly; 31-Spiral segment support; 311-Spiral groove; 3111-Semi-circular edge; 3112-Straight edge; 32-Lead wire support; 321-First bent plate-shaped support; 3211-Clamping part; 3212-First horizontal lead wire groove; 3213-First plate-shaped part; 3214-Second plate-shaped part; 322-Second bent plate-shaped support; 3221-Second horizontal lead wire groove; 4-Coil; 41-Spiral segment; 42-Upper lead wire; 43-Lower lead wire; 44-Upper connecting terminal; 45-Lower connecting terminal. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0027] Please see Figures 1 to 8 This embodiment provides a vertically molded inductor with a compact structure and reliable performance, making it particularly suitable for high-power-density power modules with limited space. It includes a shielding housing 1, a magnetic core post 2, a prefabricated support assembly 3, a coil 4, and an integrated encapsulation layer (not shown) filled inside the housing. All components are integrated into a single unit using a single encapsulation process.

[0028] The shielding shell 1 is made of a metallic material (such as copper, aluminum alloy, or nickel-plated steel). It includes an open-top outer shell 11 and a cover 12 that is detachably mounted on top by screws or clips (not shown), serving as mechanical protection, heat dissipation, and electromagnetic shielding. The magnetic core column 2 is made of a soft magnetic material with high permeability and low loss (such as manganese-zinc ferrite, nickel-zinc ferrite, or metallic magnetic powder core) and is cylindrical in shape. The prefabricated support assembly 3 is the core component for achieving high-precision manufacturing in this invention, and it includes a helical section support 31 and a lead wire support 32.

[0029] Specifically, such as combining Figure 2 , Figure 3 and Figure 4 As shown, the helical support 31 is a hollow insulating cylinder tightly fitted around the periphery of the magnetic core column 2. Its outer wall is precision-injected or machined with continuous helical grooves 311. The cross-section of the helical grooves 311 (see...) Figure 4(Enlarged view of the cross-section of the spiral groove 311) is a combination of a semi-circular arc edge 3111 and a straight edge 3112. The angle α between the line connecting the two endpoints A and B of the semi-circular arc edge 3111 and the horizontal line H is designed to be 45° (within the range of 30°-60°). The straight edge 3112 is perpendicular to the connecting line and extends radially upward along the spiral segment support 31 (i.e., away from the direction of the magnetic core column 2).

[0030] This unique groove cross-section design, compared to the semi-circular or rectangular cross-section grooves used in conventional technologies, has an opening facing outwards. During the hot pressing process after the powder is filled, the pressure acting on the powder from top to bottom will create a downward force on the coil 4. This can easily cause the spiral section 41 of the coil 4 to shift or deform, resulting in structural damage to the coil 4 itself and deterioration of the inductor's electrical performance (such as inductance drift, increased loss, and decreased stability), thus reducing the reliability of the product structure.

[0031] Through its unique groove cross-section design, this invention enables the semi-circular arc edge 3111 of the spiral groove 311 to form a supporting spiral groove that conforms to the contour of the coil 4 during the hot pressing process. This provides stable support for the bottom of the coil 4, effectively limiting its downward and inward displacement and preventing deformation and damage to the coil 4. At the same time, the flared structure formed by the straight edge 3112 can significantly optimize the filling flow of the powder, ensuring that the powder can fully fill the gaps around the coil 4, greatly improving the density of the powder around the coil 4, and providing structural protection for the stability of the inductor performance.

[0032] like Figure 4 As shown, the top of the lead support 32 is provided with a lead groove corresponding to the coil 4. The lead segment of the coil 4 is inserted into the lead groove and extends along the lead groove to the outside of the shielding housing 1. This can prevent the spiral segment 41 from being pulled or deformed under the action of encapsulation pressure and external installation stress, thereby ensuring the long-term reliability of the electrical connection.

[0033] In this embodiment, the prefabricated support assembly 3 adopts a design where the helical segment support 31 and the lead wire support 32 are detachable. This modular structure optimizes the assembly process. The coil 4 can be independently and precisely wound into the helical groove 311 of the helical segment support 31, providing ample operating space and facilitating automated production. After winding, the lead wire support 32 is then installed, improving production flexibility and efficiency.

[0034] Combination Figure 5 and Figure 6 As shown, the lead wire support 32 includes a first bent plate-shaped support 321 and a second bent plate-shaped support 322, which are integrally injection molded.

[0035] Both the first bent plate-shaped support 321 and the second bent plate-shaped support 322 have sides that are tightly attached to the helical segment support 31. The second plate-shaped support extends into the continuous helical groove 311, forming multiple downwardly extending locking portions 3211. When the lead wire support 32 is combined with the helical segment support 31, these locking portions 3211 can precisely embed into the uppermost helical groove 311 of the helical segment support 31 (the lead wire support 32 is obliquely locked into the helical segment support 31). The bottom surface shape of the locking portion 3211 is complementary to the semi-circular arc edge 3111 of the groove, and together they form a complete circular locking space that closely matches the wire diameter of the coil 4. This achieves dual radial and axial locking of the helical segment 41 during installation after the coil 4 is wound, effectively preventing displacement during subsequent hot pressing processes and significantly improving structural reliability.

[0036] At the same time, these locking parts 3211 themselves also constitute a plug-in positioning structure, so that after the lead wire support 32 and the spiral section support 31 are combined, screwless pre-fixation and self-positioning are achieved, ensuring the overall stability of the component before packaging.

[0037] Furthermore, a first horizontal lead groove 3212 is formed on the top of the first bent plate-shaped support 321, and a second horizontal lead groove 3221 is formed on the second bent plate-shaped support 322. This design provides a dedicated channel for the laying and fixing of the lead wires of the coil 4. The lead wires are confined within the grooves to the outside of the shielding housing 1, causing tension or deformation of the helical section 41 under the action of encapsulation pressure and external installation stress, thus ensuring the long-term reliability of the electrical connection.

[0038] In this embodiment, the first bent plate-shaped support 321 includes a first plate-shaped portion 3213 perpendicular to the tangential direction of the helical segment support 31 and a second plate-shaped portion 3214 parallel to the lead wire exit sidewall of the shielding shell 1. The second bent plate-shaped support 322 has the same shape as the first bent plate-shaped support 321 and is symmetrically arranged, and the second plate-shaped portions 3214 of the two are fixedly connected at opposite ends, forming a stable U-shaped whole. This symmetrical and integrated structure significantly enhances the structural rigidity of the support component itself, enabling it to act as a robust skeleton during the encapsulation process and effectively resist deformation.

[0039] On the second plate-shaped portion 3214 of the second bent plate-shaped support 322, corresponding to the ends of the upper lead 42 and lower lead 43 of the coil 4, upper connecting terminals 44 and lower connecting terminals 45 are respectively embedded. A through slot 131 is provided at the corresponding position on the lead-out sidewall of the shielding housing 1. This design not only achieves integrated and direct electrical connection, improving the mechanical strength and vibration resistance of the connection end, but also plays a crucial primary positioning role in assembly. During assembly, by moving the prefabricated support assembly 3 with the coil 4 installed, the upper connecting terminal 44 and lower connecting terminal 45 are precisely extended from the through slot 131 (at this time, the second plate-shaped portion 3214 of the second bent plate-shaped support 322 is tightly attached to the lead-out sidewall of the shielding housing 1). This process uses the through slot 131 on the housing sidewall as a reference to lock the displacement of the prefabricated support assembly 3 in the X and Z directions inside the housing.

[0040] The bottom of the magnetic core column 2 is provided with a locking groove 21, and the bottom of the shielding housing 1 is provided with a locking component 14 that matches the locking groove 21. This complementary locking structure is activated when the magnetic core column 2 is finally installed into the helical segment support component 31, achieving vertical (Y-axis) positioning. This constitutes a comprehensive mechanical interlocking positioning system, ultimately achieving complete constraint of all degrees of freedom of the prefabricated support component 3 inside the housing, ensuring the consistency of the relative positions of the coil 4, magnetic core, terminals, and housing.

[0041] In this embodiment, the lead support 32 and the spiral segment support 31 are made of the same material as the integral encapsulation layer filled inside the shielding housing 1. This material consistency design effectively reduces the interfacial stress caused by temperature changes due to material differences in the lead support 32 during the subsequent integral encapsulation process, avoiding the risk of delamination or cracking, thereby ensuring the overall structural integrity and long-term reliability of the encapsulation.

[0042] In this embodiment, the integrated encapsulation layer is made of a magnetic composite encapsulation material. This material system uses epoxy resin as a matrix, in which magnetic particles are uniformly dispersed in a specific proportion. The magnetic particles are preferably selected from one or more of iron powder, carbonyl iron, iron-silicon-aluminum, or amorphous alloy powder. The dispersed magnetic particles can guide and constrain leakage magnetic paths, reduce leakage magnetic flux, improve effective permeability, and optimize the saturation characteristics of the inductor. Simultaneously, the epoxy resin matrix ensures excellent insulation, adhesive strength, and environmental sealing protection.

[0043] The simplified process of the vertical integral molding inductor manufacturing method in this embodiment is as follows: Step 1: The spiral segment 41 of coil 4 is wound and pre-fixed in the spiral groove 311 of spiral segment support member 31 according to precise tension control to ensure the pitch and the stable shape of coil 4.

[0044] Step 2: Install the lead wire support 32, so that its locking part 3211 is accurately embedded into the uppermost spiral groove 311. Then, insert the lead wires of the coil 4 into the corresponding lead wire grooves and solder them to the upper connection terminal 44 and the lower connection terminal 45 to complete the electrical connection.

[0045] Step 3: Place the pre-assembled support assembly 3 into the shielding housing 1. Align the connecting terminals (upper connecting terminal 44 and lower connecting terminal 45) with the through groove 131 on the side wall of the housing to complete the XY plane positioning. At the same time, the engaging structure between the magnetic core column 2 and the bottom of the housing further constrains the Z-direction position, achieving all-round constraint positioning.

[0046] Step 4: Fill the shielding shell 1 with magnetic composite powder (such as a mixture of epoxy resin matrix and carbonyl iron powder) and hot press it in a vacuum environment. After cooling, a dense and high-strength integrated encapsulation layer is formed, which combines the magnetic core column 2, support assembly, coil 4 and shell into a whole.

[0047] Step 5: Install the shielding cover 12, which can be fixed with screws or clips to complete the final encapsulation of the inductor. Finally, according to the application requirements, perform surface tin plating or other treatments on these exposed connection terminals to improve their solderability and corrosion resistance.

[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A vertically molded inductor, characterized in that, It includes a shielding shell, a magnetic core column disposed within the shielding shell, a prefabricated support assembly sleeved on the outside of the magnetic core column, a spiral coil wound around the prefabricated support assembly, and an integrated encapsulation layer that fills the interior of the shielding shell and covers the prefabricated support assembly, the coil, and the magnetic core column to form an integrated structure. The prefabricated support assembly includes a spiral segment support and a lead wire support. The spiral segment support is a cylindrical structure with a continuous spiral groove on its outer wall. The cross-section of the continuous spiral groove is a combination of a semi-circular arc edge and a straight edge. The angle between the line connecting the two endpoints of the semi-circular arc edge and the horizontal line is an acute angle. The straight edge is perpendicular to the line connecting the two endpoints of the semi-circular arc edge and extends radially upward along the spiral segment support. The top of the lead support is provided with a lead groove corresponding to the spiral coil. The lead segment of the spiral coil is inserted into the lead groove and extends along the lead groove to the outside of the shielding housing.

2. The vertical integral molded inductor according to claim 1, characterized in that, The shielding housing includes an open-top shell and a cover that can be detachably installed on the top of the shell.

3. The vertically molded inductor according to claim 1, characterized in that, The lead support includes a first bent plate-shaped support corresponding to the upper lead of the coil, and a second bent plate-shaped support corresponding to the lower lead of the coil. Both the first and second bent plate-shaped supports have sides that are tightly attached to the spiral segment support. The second plate-shaped support extends into the continuous spiral groove to form a locking part. The locking part and the semi-circular arc edge of the continuous spiral groove together form a groove to enclose a closed circular space that is adapted to the diameter of the spiral coil. The lead groove includes a first horizontal lead groove formed on the top of the first plate-shaped support portion, and a second horizontal lead groove formed on the second plate-shaped support portion.

4. The vertical integral molded inductor according to claim 3, characterized in that, The first bent plate-shaped support includes a first plate-shaped part perpendicular to the tangential direction of the spiral segment support and a second plate-shaped part parallel to the side wall of the shielding shell lead wire. The second bent plate-shaped support has the same shape as the first bent plate-shaped support and is symmetrically arranged with the first bent plate-shaped support. The second plate-shaped part of the second bent plate-shaped support is fixedly connected to the opposite end of the second plate-shaped part of the first bent plate-shaped support. The second plate-shaped part of the second bent plate-shaped support is provided with an upper connecting terminal at the end position of the upper lead wire, and a lower connecting terminal is provided on the second plate-shaped part of the second bent plate-shaped support at the end position of the lower lead wire. A through groove is provided on the lead wire leading side wall of the shielding shell at the positions of the upper and lower connecting terminals. The second plate-shaped part of the second bent plate-shaped support is in close contact with the lead wire leading side wall of the shielding shell. The bottom of the magnetic core column is provided with a locking groove, and the bottom of the shielding shell is provided with a locking component that matches the locking groove.

5. The vertically molded inductor according to claim 1, characterized in that, The angle between the line connecting the two endpoints of the semicircular arc and the horizontal line is 30°-60°.

6. The vertically molded inductor according to claim 1, characterized in that, The spiral section support is made of an insulating high-temperature resistant material, which is selected from one or more of PBT, PA66, epoxy resin or LCP.

7. The vertically molded inductor according to claim 1 or 6, characterized in that, The lead wire support and the spiral segment support are made of the same material as the integrated encapsulation layer.

8. The vertically molded inductor according to claim 1, characterized in that, The integrated encapsulation layer is made of a magnetic composite encapsulation material; the magnetic composite encapsulation material includes an epoxy resin matrix and magnetic particles dispersed therein.

9. The vertically molded inductor according to claim 8, characterized in that, The magnetic particles are selected from one or more of iron powder, carbonyl iron, iron-silicon-aluminum, or amorphous alloy powder.

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