Inductor manufacturing process

Abstract

The present invention provides an inductor manufacturing process, comprising the following steps: winding a wire into a coil on a winding mold, and bending the ends of the wire to form pins for external connection; assembling the coil and the magnetic core so that the coil is wound around at least a portion of the magnetic core; placing the assembled coil and magnetic core in a first mold, performing a first injection molding of the coil and the magnetic core with an injection molding material, connecting the coil and the magnetic core into one body, and obtaining an intermediate mold; placing a ceramic heat sink and the intermediate mold in a second mold, with the inner surface of the ceramic heat sink attached to the outer circumference of the coil; performing a second injection molding of the ceramic heat sink and the intermediate mold with an injection molding material, wrapping the ceramic heat sink and the intermediate mold into one body with an injection molding layer, and obtaining an integrated inductor in which the outer surface of the ceramic heat sink and the pins are exposed in the injection molding layer. This inductor manufacturing process is used to improve the current technical problems of insufficient heat dissipation performance of inductors themselves and low production rates.

Description

Technical Field

[0001] The present invention relates to the field of inductors, and in particular to a manufacturing process of an inductor. Background Art

[0002] Currently, new energy vehicles and hybrid vehicles, characterized by electrification, are gradually replacing traditional fuel-powered vehicles and becoming a key means for countries to combat the greenhouse effect. The core of vehicle electrification is the efficient electromechanical coupling of driving through power batteries and electric motors, thereby achieving fuel savings or eliminating fuel consumption entirely. Within the operating mechanism of electrified vehicles, the charging and discharging of batteries to drive the motors is characterized by high-power voltage conversion of high-voltage electrical energy. High-power inductors are essential core components in the conversion circuits.

[0003] Currently, high-power inductors for automotive applications are typically potted with thermally conductive silicone. This silicone secures the inductor coil to the magnetic core and conducts away heat generated by the coil and core. However, the potted inductor manufacturing process is complex and results in low molding efficiency. To improve molding efficiency, injection molding is also currently being used, but this presents technical challenges in achieving a good balance between heat dissipation performance and product size. Summary of the Invention

[0004] The main technical problem solved by the present invention is to improve the current technical problems of low inductor forming efficiency and inability to give good balance between heat dissipation performance and product volume.

[0005] The solution for achieving the technical objectives of the present invention is a process for manufacturing an inductor, comprising the following steps:

[0006] The wire is wound into a coil on a winding die, and both ends of the wire are bent to form pins for external connection;

[0007] Assembling the coil and the magnetic core so that the coil is wound around at least a portion of the magnetic core; placing the assembled coil and magnetic core into a first mold, performing a first injection molding on the coil and the magnetic core with an injection molding material, and connecting the coil and the magnetic core into one body to obtain an intermediate mold;

[0008] The ceramic heat sink and the intermediate module are placed in a second mold, and the inner surface of the ceramic heat sink is attached to the outer peripheral surface of the coil; the ceramic heat sink and the intermediate module are injection molded for a second time using an injection molding material, and the ceramic heat sink and the intermediate module are wrapped into one body by an injection molding layer, thereby obtaining an integrated inductor in which the outer surface of the ceramic heat sink and the pins are exposed in the injection molding layer.

[0009] In an optional embodiment, the coil has four sides, wherein two opposite sides are first sides, and the other two opposite sides are second sides;

[0010] Winding the wire into a coil specifically includes: winding the wire on a winding die having a rectangular cross section to obtain a coil having two opposing first side surfaces and two opposing second side surfaces, wherein the area of ​​the first side surface of the coil is greater than the area of ​​the second side surface;

[0011] The inner surface of the ceramic heat sink is attached to the outer peripheral surface of the coil. Specifically, the inner surface of the ceramic heat sink is opposite to and directly contacts the first side surface of the coil.

[0012] In an optional embodiment, the wire is wound into a coil, which specifically also includes: winding the wire on a winding mold with a rectangular cross-section to obtain a coil having two opposing first side surfaces and two opposing second side surfaces, and making the ratio between the area of ​​the first side surface of the coil and the area of ​​the second side surface be no less than 2.

[0013] In an optional embodiment, the inductor manufacturing process further includes: matching the size of the ceramic heat sink, the size of the coil, and the size of the magnetic core so that the overall size of the obtained inductor satisfies: on a cross-section of the inductor perpendicular to the winding axis of the coil, the size of the inductor corresponding to the first side is L, the size of the inductor corresponding to the second side is H, and L:H ≥ 3:1.

[0014] In an optional embodiment, the ceramic heat sink and the intermediate module are subjected to a second injection molding process using an injection molding material, which specifically includes: matching the structure of the second mold with the process parameters of the second injection molding process so that the outer surface of the ceramic heat sink of the obtained integrated inductor is flush with the outer surface of the insulating layer in which it is located.

[0015] In an optional embodiment, the magnetic core includes a center column magnetic core and two yoke magnetic cores; and the inductor manufacturing process specifically includes:

[0016] Along the axial direction of the middle column magnetic core, the coil is sheathed outside the middle column magnetic core;

[0017] Placing the assembled coil and magnetic core into a first mold, specifically comprising: placing the assembled coil and middle column magnetic core into the first mold, performing a first injection molding of the coil and the middle column magnetic core with an injection molding material, connecting the coil and the middle column magnetic core into one body, and obtaining an intermediate mold;

[0018] The yoke core, ceramic heat sink and intermediate module are placed in a second mold, so that the two yoke cores are relatively placed at the axial ends of the middle column core and are both connected to the middle column core. The mold is closed so that the inner surface of the ceramic heat sink is in direct contact with the outer peripheral surface of the coil, and the ceramic heat sink, yoke core and intermediate module are injection molded for the second time using the injection molding material.

[0019] In an optional embodiment, the magnetic core also includes two bypass cores; placing the ceramic heat sink and the intermediate module in the second mold, specifically also including: placing the two yoke cores at the two ends of the intermediate module along the axial direction of the middle column core and connecting them to the two ends of the middle column core, and then placing the two bypass cores opposite to each other on both sides of the intermediate module so that the yoke core and the bypass core are connected end to end; the ceramic heat sink is fitted with the side of the coil exposed between the two bypass cores.

[0020] In an optional embodiment, the ends of the wire are bent to form pins for external connection, specifically comprising: winding the coil on a winding mold, winding the wire a set number of turns along the axial direction of the winding mold to form the main body of the coil;

[0021] The two ends of the wire are bent along the pin bending path of the winding mold respectively; the first end of the wire is bent toward the axial direction of the winding mold to form a first pin; the second end of the wire is first bent away from the first pin by a predetermined distance, and then bent three times to form a U-shaped portion for placing two yoke cores and one of the bypass cores, and finally bent once toward the axial direction of the winding mold to form a second pin, so that the first pin and the second pin are located at the same end of the coil and both extend along the winding axis of the coil.

[0022] In an optional embodiment, the number of the ceramic heat sinks is two, and the two ceramic heat sinks are arranged opposite to each other;

[0023] Placing the ceramic heat sink and the middle module in the second mold specifically includes fixing a ceramic heat sink through the upper mold and the lower mold of the second mold respectively, placing the middle module in one of the upper mold and the lower mold and fixing it, and closing the upper mold and the lower mold so that the two ceramic heat sinks are arranged relative to each other and respectively contact the two opposite sides of the coil.

[0024] In an optional embodiment, the ceramic heat sink and the intermediate module are subjected to a second injection molding process using an injection molding material, specifically including adding PPS material and subjecting the ceramic heat sink and the intermediate module to a second injection molding process using the PPS material.

[0025] According to the inductor manufacturing process of the above embodiment, a two-shot injection molding process is adopted. The secondary injection molding method connects and fixes the ceramic heat sink and the intermediate module into one piece, which can reduce the difficulty of production, improve production efficiency, and effectively take into account the flatness of the product's external surface. Compared with the inductors of the related art, the main difference is that the present invention directly uses the ceramic heat sink as part of the inductor. The thermal conductivity of the ceramic heat sink is much greater than the thermal conductivity of common soft thermal pads such as silicone thermal pads. Therefore, thanks to the excellent properties of the ceramic heat sink in all aspects, it can also take into account the overall volume control of the product and the improvement of the product's heat dissipation performance. It is different from the inductors in the related art in which part of the coil is directly exposed, both in composition and structure, and no additional thermal pad is required during application. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is a flow chart of the inductor manufacturing process disclosed in the present invention.

[0027] Figure 2 A schematic diagram of the overall structure of an inductor provided in some embodiments of the present invention.

[0028] Figure 3 for Figure 2 Exploded diagram of the inductor in Figure 1.

[0029] Figure 4 for Figure 3 Another perspective diagram of .

[0030] Figure 5 for Figure 2 Front view of the inductor.

[0031] Figure 6 for Figure 5 AA schematic diagram.

[0032] Figure 7 for Figure 5 BB schematic diagram.

[0033] Figure 8 for Figure 2 Schematic diagram of the structure of the coil in the inductor.

[0034] Figure 9 for Figure 2 Schematic diagram of the structure of the intermediate module in the inductor.

[0035] Figure 10 for Figure 2 Schematic diagram of the middle module, yoke core, bypass core and ceramic heat sink in the inductor.

[0036] Figure markings: 1000-inductor; 100-inductor assembly; 110-magnetic core; 111-middle column magnetic core; 112-sub-magnetic core; 113-yoke magnetic core; 114-bypass magnetic core; 115-avoidance part; 120-coil; 121-first side; 122-second side; 123-pin; 1231-first pin; 1232-second pin; 124-main body; 125-U-shaped part; 200-injection molding layer; 300-ceramic heat sink; 400-intermediate module. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions, and for those skilled in the art, it is not necessary to describe these related operations in detail. They will fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0038] In addition, the features, operations, or characteristics described in the specification may be combined in any appropriate manner to form various embodiments. Furthermore, the steps or actions in the method description may be reordered or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various sequences in the specification and drawings are provided solely for the purpose of clearly describing a particular embodiment and are not intended to be mandatory, unless otherwise specified.

[0039] The serial numbers assigned to components herein, such as "first," "second," etc., are used solely to distinguish the objects being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings).

[0040] The present invention discloses an inductor manufacturing process for improving the current technical problems of insufficient heat dissipation performance and low production rate of the inductor 1000. Figure 1 , the manufacturing process of the inductor 1000 includes the following steps:

[0041] The injection molding layer 200 is wrapped as a whole and the wire is wound into a coil 120 on a winding mold, and both ends of the wire are bent to form pins 123 for external connection. The pins 123 serve as a structure for electrically connecting the coil 120 of the inductor 1000 to the outside.

[0042] The coil 120 and the magnetic core 110 are assembled so that the coil 120 is wound around at least a portion of the magnetic core 110, thereby forming an inductor assembly 100 capable of generating an inductive effect. The assembled coil 120 and magnetic core 110 are placed in a first mold, and a first injection molding process is performed on the coil 120 and the magnetic core 110 using an injection molding material, thereby connecting the coil 120 and the magnetic core 110 into one piece, thereby forming an intermediate mold 400. By forming the coil 120 on the winding mold, the size of the hollow cavity of the coil 120 can be slightly larger than the size of the portion of the magnetic core 110 encasing the coil 120, while ensuring the overall shape of the coil 120 is regular. This allows a certain gap to be created between the inner surface of the coil 120 and the outer surface of the corresponding portion of the magnetic core 110. The injection molding material can enter the gap between the inner surface of the coil 120 and the magnetic core 110, thereby stably connecting and fixing the coil 120 and the magnetic core 110. At the same time, if the first mold for injection molding has a high flatness, the outer surface of the coil 120 can be shaped using the first mold and the first injection molding process, so that the outer surface of the coil 120 in the obtained intermediate module 400 also has a high flatness.

[0043] The ceramic heat sink 300 and the intermediate mold 400 are placed in a second mold, with the inner surface of the ceramic heat sink 300 attached to the outer circumference of the coil 120. A second injection molding process is performed on the ceramic heat sink 300 and the intermediate mold 400 using the injection molding material. The ceramic heat sink 300 and the intermediate mold 400 are then wrapped together by the injection-molded injection layer 200, resulting in an integrated inductor 1000 in which the outer surface of the ceramic heat sink 300 and the pins 123 are exposed through the injection layer 200.

[0044] In the above-mentioned preparation steps and steps for the second injection molding, on the one hand, since the second mold used for the second injection molding has a high degree of flatness, the appearance consistency of the product can be effectively ensured by setting the parameters of the second mold and the second injection molding process. The ceramic heat sink 300 and the intermediate module 400 are both placed in the second mold, and the injection molding material can be filled between the ceramic heat sink 300 and the intermediate module 400. Finally, the various parts of the inductor 1000 are connected and fixed by the injection molding layer 200, which can effectively improve the stability of the product, reduce the manufacturing difficulty, and improve the production efficiency of the product.

[0045] On the other hand, the ceramic heat sink 300 is a rigid component with a certain degree of compressive resistance. After mold closing and during the injection molding process, the ceramic heat sink 300 and coil 120 are tightly fitted together, increasing the contact area between the ceramic heat sink 300 and the coil 120 surface and ensuring tight contact. This allows for more uniform contact between the ceramic heat sink 300 and coil 120 at all locations, allowing heat from the coil 120 to be directly transferred to the ceramic heat sink 300 and then transferred outward from the ceramic heat sink 300. Due to the high thermal conductivity, excellent insulation properties, and airtightness of the ceramic heat sink 300, the inductor 1000 can be connected to the outside for heat exchange through the exposed ceramic heat sink 300. The ceramic heat sink 300 can exchange heat directly with the air, with external heat exchange equipment, or even directly with metal for heat dissipation. Thanks to the insulation layer and the ceramic heat sink 300, the ceramic heat sink 300 meets electrical safety requirements when connected to the outside.

[0046] In addition, the presence of the ceramic heat sink 300 can significantly improve the heat dissipation performance of the inductor 1000. Based on the significantly improved heat dissipation performance of the inductor 1000, a coil 120 with a smaller wire diameter can be selected. At the same time, since the outer surface of the coil 120 already has a high flatness during the process of obtaining the intermediate module 400 through injection molding of the first mold, and the second mold and the ceramic heat sink 300 itself also have a high flatness, the outer surface of the coil 120, the second mold and the ceramic heat sink 300 all have good flatness. This ensures that the ceramic heat sink 300 will not be damaged or cracked due to stress concentration during the second injection molding process. Therefore, a thinner ceramic heat sink 300 can be selected to be molded on the inductor 1000. The thinner ceramic heat sink 300 is sufficient to meet the requirements of electrical isolation. At the same time, the heat transfer depth from the coil 120 to the ceramic heat sink 300 to the outside can be shortened, which is conducive to faster heat exchange between the ceramic heat sink 300 and the outside. A thinner ceramic heat sink 300 combined with a coil 120 having a smaller wire diameter can significantly reduce the volume of the inductor 1000, thereby effectively reducing the overall volume of the inductor 1000 while improving the heat dissipation performance, thus achieving a good balance between heat dissipation performance and product volume.

[0047] In summary, the manufacturing process of the inductor 1000 according to the present invention utilizes a two-shot molding process, compared to solutions that secure the ceramic heat sink 300 through other methods, such as gluing or bolting. This secondary injection molding process, which connects and secures the ceramic heat sink 300 and the intermediate module 400 into an integrated unit, can significantly reduce production difficulty, improve production efficiency, and effectively maintain the flatness of the product's exterior surface. Compared to the inductor 1000 of the related art, the main difference lies in the inductor 1000 of the present invention, which incorporates the ceramic heat sink 300 directly as a component of the inductor 1000. The thermal conductivity of the ceramic heat sink 300 is far greater than that of common soft thermal pads, such as silicone thermal pads. Therefore, thanks to the excellent properties of the ceramic heat sink 300, the overall product volume can be controlled while also improving the product's heat dissipation performance. Unlike the inductor 1000 commonly found in the related art, where a portion of the coil 120 is directly exposed, the present invention differs in both composition and structure, eliminating the need for an additional thermal pad during application.

[0048] It should be noted that, in the inductor 1000 produced by the above-mentioned manufacturing process of the inductor 1000 , the ceramic heat sink 300 serves as the main heat dissipation component, and the exposed structure of the injection molding layer 200 can also play an auxiliary heat dissipation function.

[0049] The wire diameter mentioned above refers to the cross-sectional area of ​​the wire. As is common knowledge in the field, a larger wire diameter for coil 120 generates less heat, while a smaller wire diameter for coil 120 generates more heat. Therefore, inductors 1000 in the related art lack good heat dissipation performance, making it difficult to reduce the volume of coil 120. The inductor 1000 produced by the present invention allows the use of wire with a smaller diameter for coil 120.

[0050] In some embodiments, the thickness of the ceramic heat sink 300 can be configured to be 0.2 mm to 0.5 mm. Since the ceramic heat sink 300 has good insulation properties and excellent air tightness, a thinner ceramic heat sink 300 can also ensure that the electrical isolation requirements are met. Therefore, by controlling the thickness of the ceramic heat sink 300 between 0.2 mm and 0.5 mm, the size of the inductor 1000 in the direction of the thickness of the ceramic heat sink 300 can be further controlled on the basis of ensuring the performance of the inductor 1000, which is conducive to reducing the overall volume of the inductor 1000.

[0051] In some embodiments, please refer to Figure 2-Figure 10The coil 120 has four sides, two of which are opposite to each other and are first sides 121, and the other two opposite sides are second sides 122. In the manufacturing process of the inductor 1000, the wire is wound into the coil 120, specifically comprising: winding the wire on a winding die having a rectangular cross-section to obtain a coil 120 having two opposite first sides 121 and two opposite second sides 122, wherein the area of ​​the first side 121 of the coil 120 is larger than the area of ​​the second side 122. The inner surface of the ceramic heat sink 300 is attached to the outer circumference of the coil 120, specifically: the inner surface of the ceramic heat sink 300 is opposite to and in direct contact with the first side 121 of the coil 120. In other words, in a cross section perpendicular to the winding axis of the coil 120, the closed figure formed by the outer surface of the coil 120 is roughly rectangular, rather than the common square. The ceramic heat sink 300 is arranged on the outer side of the large surface of the coil 120, i.e., the first side surface 121, and the ceramic heat sink 300 is tightly fitted to the first side surface 121.

[0052] When designing an inductor 1000, prior art typically chooses to make the cross-sectional shape of the coil 120 as close to a square as possible, taking into account the inductance performance of the inductor 1000. However, the applicant has discovered that using a coil 120 with a relatively large aspect ratio in the cross-sectional shape does not significantly affect the overall performance. Furthermore, by properly arranging the coil 120 and the ceramic heat sink 300, the heat transfer area between the coil 120 and the ceramic heat sink 300 can be effectively increased, and the heat transfer depth can be shortened, thereby facilitating overall heat dissipation. Simultaneously, the improved heat dissipation performance is beneficial for reducing the overall volume of the inductor 1000. By properly reducing the wire diameter of the coil 120, the thickness dimension of the inductor 1000 and / or the corresponding axial dimension of the coil 120 can be effectively reduced, ultimately reducing or even significantly reducing the volume of the inductor 1000. The thickness dimension of the inductor 1000 is the dimension of the inductor 1000 in the thickness direction corresponding to the ceramic heat sink 300.

[0053] In some embodiments, winding the wire into the coil 120 specifically includes: winding the wire on a winding die having a rectangular cross-section to obtain a coil 120 having two opposing first side surfaces 121 and two opposing second side surfaces 122, wherein the ratio between the area of ​​the first side surface 121 and the area of ​​the second side surface 122 of the coil 120 is not less than 2. The cross-sectional dimensions of the winding die can be configured as required, as long as the ratio between the area of ​​the first side surface 121 and the area of ​​the second side surface 122 is ultimately not less than 2. By ensuring that the ratio between the area of ​​the first side surface 121 and the area of ​​the second side surface 122 of the coil 120 is not less than 2, the heat dissipation area of ​​the coil 120, the contact area between the coil 120 and the ceramic heat sink 300, and the depth of the heat transfer path are significantly increased. Combined with the auxiliary heat dissipation provided by the ceramic heat sink 300, the heat dissipation performance of the inductor 1000 can be significantly improved.

[0054] In some coils 120 with rounded corners, the intersection area of ​​the corners can be included in the calculation of the first side surface 121 and the second side surface 122, so that the ratio of the area of ​​the first side surface 121 to the area of ​​the second side surface 122 is not less than 2. Alternatively, the length dimension a corresponding to the first side surface 121 of the coil 120 and the length dimension b corresponding to the second side surface 122 of the coil 120 can be used as a measurement standard. In other words, the coil 120 can be directly ensured to meet the following requirement: the ratio of the length dimension a corresponding to the first side surface 121 of the coil 120 to the length dimension b corresponding to the second side surface 122 of the coil 120 is not less than 2.

[0055] In some embodiments, the manufacturing process for inductor 1000 further includes matching the dimensions of the ceramic heat sink 300, the coil 120, and the magnetic core 110 so that the overall dimensions of the resulting inductor 1000 satisfy the following conditions: in a cross-section of the inductor 1000 perpendicular to the winding axis of the coil 120, the dimension of the inductor 1000 corresponding to the first side 121 is L, and the dimension of the inductor 1000 corresponding to the second side 122 is H, with L:H ≥ 3:1. By increasing the aspect ratio of the entire product, ensuring that the aspect ratio is no less than 3, the heat transfer depth of the coil 120 can be further shortened. Furthermore, a larger dimension L of the molded layer 200 formed by the second injection molding process increases the size and heat dissipation area of ​​the ceramic heat sink 300, thereby further increasing the heat dissipation area between the ceramic heat sink 300 and the coil 120.

[0056] In some embodiments, a second injection molding process is performed on the ceramic heat sink 300 and the intermediate mold 400 using an injection molding material. Specifically, the second mold structure and the process parameters of the second injection molding process are matched to ensure that the outer surface of the ceramic heat sink 300 of the resulting integrated inductor 1000 is flush with the outer surface of the insulating layer. By ensuring that the ceramic heat sink 300 does not protrude from the side of the injection molding layer 200, the thickness dimension of the inductor 1000 relative to the ceramic heat sink 300 can be controlled, effectively shortening the heat transfer path, thereby achieving a balance between heat dissipation performance and volume control of the inductor 1000. In addition, since the outer surface of the ceramic heat sink 300 is flush with the outer surface of the side surface of the injection-molded layer 200, the side surface of the ceramic heat sink 300 of the inductor 1000 is flat. Therefore, when in use, the ceramic heat sink 300 and the side surface of the injection-molded layer 200 can be in contact and connected with the external structure at the same time. The ceramic heat sink 300 and the injection-molded layer 200 can simultaneously achieve contact heat exchange with the external structure, which can increase the overall heat exchange area between the inductor 1000 and the external structure.

[0057] In some embodiments, the coil 120 has rounded corners at all four corners, the inner surface of the ceramic heat sink 300 is attached to the surface of the coil 120, and a corner gap space is formed between the corner of the coil 120 and the ceramic heat sink 300, and the outer surface of the ceramic heat sink 300 is more protruding than the coil 120 and the magnetic core 110 as a whole, so that the injection molding material flows into the corner gap space, and the ceramic heat sink 300 and the coil 120 are connected. The outer surface of the ceramic heat sink 300 can be made flush with the outer surface of the injection molding layer 200 by setting parameters, and then the outer surface of the ceramic heat sink 300 is exposed to the injection molding layer 200 to increase the heat dissipation area of ​​the ceramic heat sink 300.

[0058] In some embodiments, please refer to Figure 2-Figure 3 The inductor 1000 can be configured such that the area of ​​the ceramic heat sink 300 exposed from the molded layer 200 is S1, and the area of ​​the side of the molded layer 200 where the ceramic heat sink 300 is located is S2, satisfying S1:S2 ≥ 30%, thereby further improving the overall heat dissipation performance of the inductor 1000. For example, the percentage of S1:S2 can be 30%, 35%, 38%, 40%, 45%, or 50%, etc.

[0059] The above-mentioned “coil 120 is wound around the magnetic core 110 ” means that, in some embodiments, the magnetic core 110 may have multiple parts, and the coil 120 may be wound around only part of the magnetic core 110 . In other embodiments, the magnetic core 110 may be a complete structure, and the coil 120 may be directly wound around the outside of the magnetic core 110 .

[0060] In some embodiments, please refer to Figure 3-Figure 7 The magnetic core 110 includes a center magnetic core 111 and two yoke magnetic cores 113; the manufacturing process of the inductor 1000 specifically includes:

[0061] The coil 120 is sheathed around the center column magnetic core 111 along the axial direction of the center column magnetic core 111. The assembled coil 120 and the center column magnetic core 111 are placed in a first mold, and the coil 120 and the center column magnetic core 111 are subjected to a first injection molding process using an injection molding material. The coil 120 and the center column magnetic core 111 are integrally connected to obtain an intermediate module 400.

[0062] The yoke core 113, ceramic heat sink 300, and intermediate mold 400 are placed in a second mold, with the two yoke cores 113 positioned opposite each other at the axial ends of the center core 111 and connected to the center core 111. The molds are closed so that the inner surface of the ceramic heat sink 300 is in direct contact with the outer circumference of the coil 120. A second injection molding process is then performed on the ceramic heat sink 300, yoke core 113, and intermediate mold 400 using the injection molding material. The two yoke cores 113 are electrically connected through the center core 111, forming a protective structure around the center core 111 and coil 120. While improving inductance performance, the two yoke cores 113 also assist in positioning the intermediate mold 400 within the second mold, and to a certain extent, improve the stiffness and compressive strength of the inductor assembly 100. The molded layer 200 formed by the second injection molding process covers the intermediate mold 400, ceramic heat sink 300, and the two yoke cores 113.

[0063] In some embodiments, please refer to Figure 7 The center core 111 may include at least two sub-cores 112, which are arranged in sequence along the winding axis. A wire of the coil 120 is wound around each sub-core 112 to enhance the inductance of the center core 111. For example, in some embodiments, the number of sub-cores 112 may be three.

[0064] In some embodiments, please refer to Figure 3 、 Figure 4 、 Figure 6 and Figure 10 The magnetic core 110 also includes two bypass cores 114; the ceramic heat sink 300 and the intermediate module 400 are placed in the second mold, specifically including: placing two yoke cores 113 at both ends of the intermediate module 400 along the axial direction of the central column core 111 and connecting them to the two ends of the central column core 111, and then placing two bypass cores 114 on both sides of the intermediate module 400 so that the yoke cores 113 and the bypass cores 114 are connected end to end; the ceramic heat sink 300 is in contact with the side of the coil 120 exposed between the two bypass cores 114. On the one hand, it is convenient to assemble the yoke cores 113, the bypass cores 114 and the intermediate module 400. On the other hand, the magnetic core 110 includes multiple independent parts, and the yoke cores 113 and the bypass cores 114 are both flat, without inflection points and corner structures, which further simplifies the structure and is conducive to further improving the inductance performance of the inductor component 100. The two yoke cores 113 and the two bypass cores 114 are connected to each other, and the two yoke cores 113 and the two bypass cores 114 together form a rectangular protection frame, which further improves the inductance performance, stiffness and compressive resistance.

[0065] In some embodiments, both pins 123 can be located on either side of the injection-molded layer 200. That is, in different embodiments, the two pins 123 can be located on the same side of the injection-molded layer 200 or on different sides of the injection-molded layer 200. To control the total volume of the coil 120 and the magnetic core 110, escape portions 115 for the wires to pass through are provided on two of the two yoke magnetic cores 113 and the two bypass magnetic cores 114.

[0066] In some embodiments, please refer to Figure 3 and Figure 4 , the two yoke cores 113 are both provided with an avoidance portion 115 , and the two pins 123 are located on the same side of the injection molding layer 200 . In the manufacturing process of the inductor 1000, the two ends of the wire are bent to form pins 123 for external connection, which specifically includes: winding the coil 120 on a winding mold, and winding the wire a set number of turns along the axial direction of the winding mold to form the main part 124 of the coil 120; bending the two ends of the wire along the bending path of the pin 123 of the winding mold; the first end of the wire is bent in the axial direction of the winding mold to form a first pin 1231; the second end of the wire is first bent away from the first pin 1231 by a predetermined distance, and then bent three times to form a U-shaped portion 125 for placing two yoke cores 113 and one of the bypass cores 114, and finally bent once in the axial direction of the winding mold to form a second pin 1232, so that the first pin 1231 and the second pin 1232 are located at the same end of the coil 120 and both extend along the winding axis of the coil 120. On the one hand, the second end of the wire is bent multiple times and extended around the yoke core 113 and the bypass core 1141, effectively controlling the overall volume of the inductor assembly 100. The yoke core 113 and the bypass core 114 also provide rigid support for the wire. On the other hand, the first pin 1231 and the second pin 1232 are positioned on the same side of the injection molding layer 200, and the first pin 1231 and the second pin 1232 extend in the same direction, facilitating external electrical connections for the inductor 1000.

[0067] In some embodiments, the ceramic heat sink 300 can be attached to the outer surface of the coil 120 before the second mold is closed. In other embodiments, the ceramic heat sink 300 can be attached to the outer surface of the coil 120 after the second mold is closed. Adaptive adjustments can be made according to actual needs and circumstances.

[0068] The above-mentioned inductor 1000 may include two or more ceramic heat sinks 300. In some embodiments, if there is a higher requirement for the heat dissipation performance of the inductor 1000, more than two ceramic heat sinks 300 may be provided. The heat dissipation rate can be further improved by using two or more ceramic heat sinks 300 on different sides. That is, the number of ceramic heat sinks 300 can be adaptively adjusted according to actual needs.

[0069] In some embodiments, please refer to Figure 3 、 Figure 4 and Figure 10 There are two ceramic heat sinks 300, which are arranged opposite each other. The manufacturing process for the inductor 1000 of the present invention places the ceramic heat sinks 300 and the intermediate mold 400 in a second mold. The process specifically includes: securing one ceramic heat sink 300 via the upper and lower molds of the second mold, securing the intermediate mold 400 in one of the upper and lower molds, and closing the upper and lower molds so that the two ceramic heat sinks 300 are arranged opposite each other and contact two opposing side surfaces of the coil 120. This allows the two ceramic heat sinks 300 to be pre-positioned in the upper and lower molds, respectively, to ensure the flatness of the final product's exterior surface.

[0070] The present invention does not limit the selection of injection materials and molding preparation schemes for the first injection molding and the second injection molding. Any material feasible in the prior art, such as PPS, PA, PET, etc., will not be described in detail here. Please refer to the relevant technology for details.

[0071] In some embodiments, the ceramic heat sink 300 and the intermediate module 400 are injection molded for a second time using an injection molding material, specifically including adding PPS material and injection molding the ceramic heat sink 300 and the intermediate module 400 for a second time using the PPS material.

[0072] To meet the requirements of automotive use, including ultra-wide operating temperature ranges, severe mechanical vibration and shock, high-voltage insulation, and high-power heat dissipation, high-power inductors are often integrally molded using engineering plastics such as PPS, which offer excellent heat resistance, insulation, thermal conductivity, resistance to high and low temperature thermal shock, oil resistance, and extremely high mechanical strength. This significantly increases the energy storage density of high-power inductors. Understandably, PPS can also be used as the molding material for the first injection molding.

[0073] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A process for manufacturing an inductor, characterized in that: The following steps are involved: The wire is wound into a coil on a winding die, and both ends of the wire are bent to form pins for external connection; Assembling the coil and the magnetic core so that the coil is wound around at least a portion of the magnetic core; placing the assembled coil and magnetic core into a first mold, performing a first injection molding on the coil and the magnetic core with an injection molding material, and connecting the coil and the magnetic core into one body to obtain an intermediate mold; The ceramic heat sink and the intermediate module are placed in a second mold, and the inner surface of the ceramic heat sink is attached to the outer peripheral surface of the coil; the ceramic heat sink and the intermediate module are injection molded for a second time using an injection molding material, and the ceramic heat sink and the intermediate module are wrapped into one body by an injection molding layer, thereby obtaining an integrated inductor in which the outer surface of the ceramic heat sink and the pins are exposed in the injection molding layer.

2. The inductor manufacturing process according to claim 1, wherein: The coil has four sides, two opposite sides are first sides, and the other two opposite sides are second sides; Winding the wire into a coil specifically includes: winding the wire on a winding die having a rectangular cross section to obtain a coil having two opposing first side surfaces and two opposing second side surfaces, wherein the area of ​​the first side surface of the coil is larger than the area of ​​the second side surface; The inner surface of the ceramic heat sink is attached to the outer peripheral surface of the coil, specifically: the inner surface of the ceramic heat sink is opposite to and directly contacts the first side surface of the coil.

3. The inductor manufacturing process according to claim 2, wherein: The method of winding the wire into a coil specifically includes: winding the wire on a winding mold with a rectangular cross-section to obtain a coil having two opposing first side surfaces and two opposing second side surfaces, and making the ratio between the area of ​​the first side surface of the coil and the area of ​​the second side surface be no less than 2.

4. The inductor manufacturing process according to claim 2, wherein: The inductor manufacturing process also includes: matching the size of the ceramic heat sink, the size of the coil, and the size of the magnetic core so that the overall size of the obtained inductor satisfies: in a cross-section of the inductor perpendicular to the winding axis of the coil, the size of the inductor corresponding to the first side is L, the size of the inductor corresponding to the second side is H, and L:H ≥ 3:

1.

5. The inductor manufacturing process according to claim 1, wherein: The second injection molding of the ceramic heat sink and the intermediate module using the injection molding material specifically includes: matching the structure of the second mold with the process parameters of the second injection molding so that the outer surface of the ceramic heat sink of the obtained integrated inductor is flush with the outer surface of the insulating layer in which it is located.

6. The inductor manufacturing process according to claim 1, wherein: The magnetic core includes a center column magnetic core and two yoke magnetic cores; the inductor manufacturing process specifically includes: Along the axial direction of the middle column magnetic core, the coil is sheathed outside the middle column magnetic core; Placing the assembled coil and magnetic core into the first mold specifically includes: placing the assembled coil and the center column magnetic core into the first mold, performing a first injection molding of the coil and the center column magnetic core with an injection molding material, connecting the coil and the center column magnetic core into one body, and obtaining an intermediate mold; The yoke core, the ceramic heat sink and the intermediate module are placed in a second mold, so that the two yoke cores are relatively placed at the axial ends of the middle column core and are both connected to the middle column core. The mold is closed so that the inner surface of the ceramic heat sink is in direct contact with the outer peripheral surface of the coil, and the ceramic heat sink, the yoke core and the intermediate module are injection molded for the second time using the injection molding material.

7. The inductor manufacturing process according to claim 6, wherein: The magnetic core also includes two bypass magnetic cores; placing the ceramic heat sink and the intermediate module in the second mold, specifically also including: placing two yoke magnetic cores at both ends of the intermediate module along the axial direction of the middle column magnetic core and connecting them to the two ends of the middle column magnetic core, and then placing the two bypass magnetic cores opposite to each other on both sides of the intermediate module so that the yoke magnetic core and the bypass magnetic core are connected end to end; the ceramic heat sink is fitted with the side of the coil exposed between the two bypass magnetic cores.

8. The inductor manufacturing process according to claim 7, wherein: The step of bending the two ends of the wire to form pins for external connection specifically includes: winding the coil on a winding die, winding the wire a set number of turns along the axial direction of the winding die to form the main body of the coil; The two ends of the wire are bent along the pin bending path of the winding mold respectively; the first end of the wire is bent toward the axial direction of the winding mold to form a first pin; the second end of the wire is first bent away from the first pin by a predetermined distance, and then bent three times to form a U-shaped portion for placing two yoke cores and one of the bypass cores, and finally bent once toward the axial direction of the winding mold to form a second pin, so that the first pin and the second pin are located at the same end of the coil and both extend along the winding axis of the coil.

9. The inductor manufacturing process according to claim 1, wherein: There are two ceramic heat sinks, which are arranged opposite to each other. Placing the ceramic heat sink and the intermediate module in the second mold specifically includes fixing a ceramic heat sink through the upper mold and the lower mold of the second mold respectively, placing the intermediate module in one of the upper mold and the lower mold and fixing it, and closing the upper mold and the lower mold so that the two ceramic heat sinks are arranged opposite to each other and respectively contact the two opposite sides of the coil.

10. The inductor manufacturing process according to claim 1, wherein: The second injection molding of the ceramic heat sink and the intermediate module using the injection molding material specifically includes adding PPS material and performing the second injection molding of the ceramic heat sink and the intermediate module using the PPS material.

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