Hot-pressing integrally-formed inductor

Abstract

The utility model discloses a hot-pressing integrated inductor which is composed of a T-shaped magnetic core, a square-shaped magnetic core, a sheet-type magnetic core and a coil which are preformed, the T-shaped magnetic core is provided with a bottom plate and a stand column body, the top face of the stand column body extends upwards in an integrated mode, and the coil is formed into a hollow spiral winding section through metal wires. The winding section is connected to the stand column body in a sleeved mode, the two free ends of the winding section extend in the same direction in parallel and are continuously bent to wrap the bottom plate to form a crank arm section, an assembly of the coil and the T-shaped magnetic core is inserted into the square-shaped magnetic core in an inverted mode, and the crank arm section is partially higher than the surface of the square-shaped magnetic core. In a hot-press forming die, the chip type magnetic core support bottom is packaged into a whole in a hot-press mode, and the protruding part corresponding to the continuous bending section is provided with an electrode bonding pad. By applying the inductor, the centering position of the coil can be effectively controlled, and the density of magnetic powder in a product and the performance of an inductance device are improved. The operation environment of the circuit is further improved, and hardware performance development under multiple application scenes is promoted.

Description

Technical Field

[0001] This utility model relates to an inductor, and more particularly to a thermo-pressed integrally molded inductor with optimized coil placement, belonging to the technical field of basic electronic components. Background Technology

[0002] Inductors are one of the most commonly used components in electronic devices, widely used in various circuits to perform functions such as filtering, energy storage, matching, and resonance. With the increasing miniaturization and portability of electronic products, and the high-density assembly of components, inductor components have developed rapidly. Furthermore, considering electromagnetic compatibility, the ability of electronic products to resist electromagnetic interference has become a basic design requirement, thus increasing the demand for and application of inductors.

[0003] Inductors are widely used in DC-DC converter buck circuits and play a crucial role in the conversion efficiency of these circuits, thus restricting the development of big data processing hardware to some extent. Inductors are typically a combination structure of a coil wrapped around a magnetic core. However, when the wound coil is assembled with a pre-fabricated magnetic core or directly encapsulated with magnetic core powder, it is prone to displacement and misalignment due to external forces, severely affecting product performance and making it difficult to improve yield. Summary of the Invention

[0004] The purpose of this invention is to propose a thermo-pressed integrally molded inductor, which aims to improve the performance of inductor devices and their adaptability to various application scenarios.

[0005] The technical solution of this utility model to achieve the above-mentioned objective is: a thermo-pressed integrally molded inductor, characterized in that: the inductor is composed of a pre-formed T-shaped magnetic core, a U-shaped magnetic core, a sheet magnetic core, and a coil; the T-shaped magnetic core has a base plate and a column extending integrally with its top surface facing upward; the coil is formed from metal wire into a hollow spiral winding segment, and the winding segment is sleeved on the column; the two free ends of the winding segment extend in the same direction and parallel, and continuously bend to wrap around the base plate, forming a curved arm segment; the assembly of the coil and the T-shaped magnetic core is inserted upside down into the U-shaped magnetic core, and the curved arm segment is partially higher than the surface of the U-shaped magnetic core; in the thermo-pressing mold, the sheet magnetic core supports the inductor and it is thermo-pressed and packaged into an integral unit; the protruding part corresponding to the continuous bending segment is set as an electrode pad.

[0006] Furthermore, the four corners of the base plate are recessed to form notches, a portion of the curved arm segment is embedded to wrap a pair of notches on the corresponding side, and another portion of the curved arm segment is embedded to wrap another pair of notches on the corresponding side. The size of the notches corresponds to the cross-section of the metal wire, satisfying that the curved arm segment is recessed within the four sides of the base plate.

[0007] Furthermore, the end of the curved arm segment is folded over and closed in the notch.

[0008] Furthermore, the T-shaped magnetic core, the square-shaped magnetic core, and the sheet magnetic core are all cold-pressed molded bodies, which are made based on molds with customized shapes and filling powder materials.

[0009] Furthermore, the metal wire of the coil is an insulated, enameled flat copper wire.

[0010] Furthermore, the top of the hot pressing mold is provided with a shallow groove corresponding to a local part of the curved arm section, so that the local part of the curved arm section in the hot pressing semi-finished product remains raised.

[0011] Compared with existing technologies, the advantages of this hot-pressed integrally molded inductor are as follows: by optimizing the shape and assembly structure of the prefabricated magnetic core and the shape of the matching coil, the coil centering position can be effectively controlled, improving the density of magnetic powder and the performance of the inductor. This is beneficial for further improving the circuit's operating environment and promoting the development of hardware performance in application scenarios such as AI servers, data centers, GPGPUs, and ADAS automotive electronics. Attached Figure Description

[0012] Figure 1 This is an exploded view of the structure of the dual inductors of this utility model.

[0013] Figure 2 This is a schematic diagram illustrating the evolution of the external shape during the assembly and manufacturing of this utility model. Detailed Implementation

[0014] 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.

[0015] This utility model proposes a thermo-pressed integrally molded inductor. For example... Figure 1 and Figure 2As shown, the basic structure of this inductor consists of a pre-formed T-shaped magnetic core 11, a U-shaped magnetic core 12, a plate magnetic core 13, and a coil 2. Looking at each functional component, the T-shaped magnetic core 11 has a base plate 111 and a column 112 extending integrally upwards from its top surface. In the illustrated embodiment, its shape is cylindrical, but it could also be another multi-faceted square column. The coil 2 is formed from metal wire into a hollow spiral winding segment 21, which is fitted onto the column 112. Due to the spiral winding, the coil has a free end on both the bottom and top sides, extending in the same direction. When it reaches a plane parallel to the central axis, it bends downwards for a distance. Obviously, the downward bend of the free end on the top side is longer, and both free ends bend in the opposite direction to their previous extension at the same horizontal position (i.e., the bottom of the base plate), then bend again to wrap around the base plate 111, forming a curved arm segment 22. The coil 2 and the T-shaped magnetic core 11 assembly A are inverted and inserted into the U-shaped magnetic core 12, with the curved arm section partially higher than the surface of the U-shaped magnetic core. They are then thermo-pressed and packaged as a single unit in a thermoforming mold, supported by a sheet magnetic core 13. If necessary, as the basis for the inductor to connect to the PCB, the exposed parts of the corresponding clips need to be stripped of paint and electroplated after thermo-pressing and painting to serve as electrode pads.

[0016] Based on this overview of the technical solution, the detailed features of each functional component include: such as Figure 1 As shown, the four corners of the base plate 111 of the T-shaped magnetic core are recessed to form notches, making the projected shape of the base plate cross-shaped. Therefore, when assembling the coil with the T-shaped magnetic core, a portion of the curved arm segment (i.e., the extended bent portion of the bottom free end) is embedded and wrapped around a pair of notches 1111a on the corresponding side, and another portion of the curved arm segment (i.e., the portion of the top free end) is embedded and wrapped around another pair of notches 1111b on the corresponding side, without forming additional protrusions, thus helping to reduce the width of the inductor in a certain direction. For this purpose, the size of the notch needs to correspond to the cross-section of the metal wire to ensure that the curved arm segment is laterally recessed within the four sides of the base plate.

[0017] Furthermore, in this embodiment, the metal wire of the coil is an insulated, enameled flat copper wire. Based on the aforementioned prefabrication and forming shape of the coil, it is important to understand that the coil's forming is completed concurrently with its assembly. That is, when it is fitted onto the column, the two free ends are not fully bent; only after it is positioned and contacts the base plate surface can subsequent continuous bending be performed to wrap around the base plate and secure it to itself. In the preferred embodiment shown in the figure, the end of the curved arm section is folded over and closed within the notch.

[0018] As a further optimization, the top of the hot pressing mold is provided with shallow grooves corresponding to the local area of ​​the curved arm section, so that the local area of ​​the corresponding curved arm section in the hot pressing semi-finished product remains raised and is separated from each other by a distance, which facilitates the subsequent paint peeling and electroplating process, and also enables the dual inductors to quickly release the heat generated during actual operation.

[0019] like Figure 2 As shown in the complete manufacturing process of this thermo-pressed integrated inductor, the following steps are taken: First, T-shaped magnetic cores, U-shaped magnetic cores, plate magnetic cores, and coils are prefabricated in the required proportions. Then, the coils are fitted onto the pillar of the T-shaped magnetic core, allowing the downward-facing free ends of each coil to fall into the notches for initial positioning. Next, all free ends are bent close to the bottom surface of the base plate, and each free end is then bent upwards into the notch on the same side at the far end, achieving the encapsulation and positioning function and obtaining assembly A. It is then inserted inverted into the U-shaped magnetic core, and supported by the plate magnetic core. This ensures that the top of the pillar and the bottom of the U-shaped magnetic core are in contact with the plate magnetic core, resulting in a complete assembly B, which is then transferred to a thermo-pressing mold. It is then encapsulated into a single unit under a temperature of 100-200℃ and a pressure of 4-10 Tons / cm², typically with a molding time of 30-180 seconds, adjusted according to actual conditions. After demolding, the product is baked at 100-180℃ for a period of time to fully solidify and set. Then, a full-coverage spray painting is performed on the surface of the inductor semi-finished product, and laser stripping is applied to the raised parts of the curved arm section (along with the insulating varnish on the surface of the metal wires), resulting in the semi-finished product C at the end of the process. Finally, electroplating is performed on the exposed copper surface to generate clearly spaced electrode pads at the bottom of the device, resulting in the finished product D.

[0020] The aforementioned T-shaped, U-shaped, and plate-type magnetic cores are all cold-pressed molded bodies. These cold-pressed molded bodies are made based on a mold with a customized shape and filled with powder material. The powder material used for pre-forming the above three types of magnetic cores can be one or more mixtures of Fe-based / FeSi / FeSiCr / FeSiAl / FeNi / amorphous / nanocrystalline materials, with one of epoxy resin, silicone resin, or acrylic resin added and stirred evenly before being injected into a pre-formed mold conforming to the device's shape. The selectable molding pressure range is 6-10 Tons / cm².

[0021] In summary, the advantages of this novel thermo-pressed integrated inductor are as follows: by optimizing the shape and assembly structure of the prefabricated magnetic core and the shape of the matching coil, the coil centering position can be effectively controlled, improving the density of magnetic powder and the performance of the inductor. This is beneficial for further improving the circuit's operating environment and promoting the development of hardware performance in application scenarios such as AI servers, data centers, GPGPUs, and ADAS automotive electronics.

[0022] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A thermo-pressed integrally molded inductor, characterized in that: The inductor is composed of a pre-formed T-shaped magnetic core, a U-shaped magnetic core, a plate magnetic core, and a coil. The T-shaped magnetic core has a base plate and a column extending integrally with its top surface facing upwards. The coil is formed from metal wire into a hollow spiral winding segment, which is sleeved on the column. The two free ends of the winding segment extend in the same direction and parallel, and are continuously bent to wrap around the base plate, forming a curved arm segment. The assembly of the coil and the T-shaped magnetic core is inserted upside down into the U-shaped magnetic core, with the curved arm segment partially higher than the surface of the U-shaped magnetic core. In a hot-press forming mold, the plate magnetic core supports the assembly and it is hot-pressed into a whole. The protruding part corresponding to the continuous bending segment is set as an electrode pad.

2. The thermo-pressed integrally molded inductor according to claim 1, characterized in that: The four corners of the base plate are recessed to form notches. A portion of the curved arm section is embedded to wrap around a pair of notches on the corresponding side, and another portion of the curved arm section is embedded to wrap around another pair of notches on the corresponding side. The size of the notches corresponds to the cross-section of the metal wire, satisfying that the curved arm section is recessed within the four sides of the base plate.

3. The thermo-pressed integrally molded inductor according to claim 2, characterized in that: The end of the curved arm section is folded over and closed in the notch.

4. The thermo-pressed integrally molded inductor according to claim 1, characterized in that: The T-shaped magnetic core, the square-shaped magnetic core, and the sheet magnetic core are all cold-pressed molded bodies, which are made based on molds with customized shapes and filled with powder materials.

5. The thermo-pressed integrally molded inductor according to claim 1, characterized in that: The coil's metal wire is an insulated, enameled flat copper wire.

6. The thermo-pressed integrally molded inductor according to claim 1, characterized in that: The top of the hot-press forming mold is provided with a shallow groove corresponding to the local part of the curved arm section, so that the local part of the curved arm section in the hot-press forming semi-finished product remains convex.

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