Coupling inductor
By designing the U-shaped coil and the T-shaped magnetic core in the coupled inductor and filling with magnetic powder, the leakage inductance and space occupation problems of traditional inductors are solved, and the effect of high coupling rate and miniaturization is achieved, which is suitable for modern electronic devices.
Patent Information
- Application Number
- CN202420915363.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-29
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2034-04-29
AI Technical Summary
The uneven gap between the inner and outer coils of traditional coupling inductors leads to leakage inductance, reducing coupling rate, and complex electrode structure, increasing circuit wiring difficulty and space occupied, which cannot meet the miniaturization needs of electronic devices.
Two U-shaped coils covered with insulating are designed to assemble with T-shaped magnetic cores, fill the gap with magnetic powder packaging to form a high coupling rate coupling inductor, optimize the electrode layout to reduce duty.
It effectively reduces electromagnetic interference radiation, improves coupling rate, meets the miniaturization needs of electronic devices, and is suitable for fields such as artificial intelligence, data centers and autonomous driving.
Smart Images
Figure CN222300430U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to an inductor device, in particular to a coupled inductor with a relatively high coupling rate, and belongs to the technical field of basic electronic components. Background Art
[0002] Inductors are the most commonly used components in electronic devices and are widely used in various circuits to achieve the functions of filtering, energy storage, matching, and resonance. As electronic products become increasingly miniaturized and portable, and components are assembled with high density, inductor components have developed rapidly; and in consideration of electromagnetic compatibility, the ability of electronic products to resist electromagnetic interference has become a basic design requirement, which has increased the demand and application of inductors.
[0003] Generally, the uneven gap between the main coil and the secondary coil (especially for enameled round wire) of a coupled inductor with internal and external leads is prone to leakage inductance, which reduces the coupling rate of the inductor. In addition, the electrode structure of the traditional coupled inductor will greatly increase the difficulty of wiring the circuit containing multiple coupled inductors, and the inductor device occupies a large space in the PCB board after soldering, which cannot conform to the design trend of miniaturization of electronic equipment. Summary of the invention
[0004] In view of the above-mentioned defects in the prior art, the purpose of the utility model is to provide a coupled inductor to suppress electromagnetic interference radiation by optimizing the internal structure of the device.
[0005] The technical solution for achieving the above-mentioned purpose of the utility model is: a coupled inductor, which is composed of two coils covered with insulation and a T-shaped magnetic core, and the whole is wrapped with magnetic powder and packaged into one body, characterized in that: each coil body is formed into a U-shape and the open end is bent to one side to form two column legs, the two coil openings are facing opposite directions and are superimposed and wound together, the four column legs are facing the same direction and form a leakage hole in the middle, the T-shaped magnetic core is integrally formed with a convex column on the bottom plate, and the convex column is connected to the leakage hole in the opposite direction of the column legs, the two coils and the T-shaped magnetic core are assembled with gap matching, and the magnetic powder completely wraps the assembly, fills the gap and is packaged and solidified.
[0006] Furthermore, the two coils are enameled wires of the same color or different colors, and the enameled wires are classified into round wires, square column wires or flat wires according to their cross-sectional shapes.
[0007] Furthermore, among the two coils, the bent column leg of the first coil is longer than the bent column leg of the second coil, the first coil is superimposed on the upper side of the second coil, and the bottom ends of the four column legs are flush.
[0008] Furthermore, the bottom plate is provided with notches at four corners, and the four column legs are aligned and connected to the notches in the assembled state.
[0009] Furthermore, among the two coils, the bent column legs of the first coil are distributed on one short side of the coupled inductor, and the bent column legs of the second coil are distributed on the other short side of the coupled inductor, and when the coupled inductor is welded to the PCB board, the two column legs distributed on the corresponding long side serve as current input terminals.
[0010] Compared with the prior art, the advantages of applying the coupled inductor of the utility model are reflected in the following aspects: the inductor is formed by designing two U-shaped enameled coils superimposed and wound together and packaged with a T-shaped magnetic core. On the one hand, the electric field and magnetic field of the two coils in the inductor can offset each other at a high ratio, which can effectively reduce the electromagnetic interference radiation of the product in practical applications. It has been verified by Ansys maxwell simulation that the coupled inductor obtained by the structural improvement has a higher coupling rate, and the coupling coefficient K is less than -0.2; on the other hand, the electrode layout as the current input terminal is optimized, which can effectively save the space occupied by the inductor device in the circuit, which is conducive to the miniaturization of electronic equipment and meets the applications in industries such as artificial intelligence AI, data centers, autonomous driving and smart cities. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 It is a perspective schematic diagram of the internal structure of the finished coupled inductor of the utility model.
[0012] Figure 2 yes Figure 1 Schematic diagram of the forming and superimposed and inter-winding combination of the two coils in the coupled inductor shown.
[0013] Figure 3 yes Figure 1 Schematic diagram of the state changes during the complete production process of the coupled inductor shown.
[0014] Figure 4 It is a current input diagram of the coupled inductor simulation of the utility model.
[0015] Figure 5 It is a schematic diagram of the mutual cancellation of two magnetic fields under the simulation of the coupled inductor H of the utility model.
[0016] Figure 6 It is a schematic diagram of the mutual cancellation of two magnetic fields under the simulation of the coupled inductor B of the utility model. DETAILED DESCRIPTION
[0017] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.
[0018] As is well known in the art, the conventional structure of a coupled inductor is composed of a two-stage coil and a T-shaped magnetic core, and each coil generates an inductance by interacting with the magnetic core when powered on. While ensuring the insulation between the two coils, the coupling rate between them is an important performance parameter of the inductor device. At the same time, its external electromagnetic interference radiation suppression is also a key point for the device structure designers. In order to suppress electromagnetic interference radiation, the present application optimizes the internal structure of the device, such as Figures 1 to 3 As shown, the main body of the first coil 1 is formed into a U shape and the open end is bent toward one side to form two column legs 11, 12, and the main body of the second coil 2 is formed into a U shape and the open end is also bent toward one side to form two column legs 21, 22. When the two coils are assembled, they are stacked and wound in opposite directions, so that the four column legs are in the same direction and a leakage hole 123 is formed in the middle. As another assembly of the coupled inductor, the T-shaped magnetic core 3 is integrally formed with a protrusion 31 on the bottom plate 32, and the protrusion 31 is inserted into the leakage hole 123 in the opposite direction of the column legs. When the two coils and the T-shaped magnetic core 3 are assembled with gap fit, the assembly is completely wrapped with magnetic powder, the gap is filled, and the package is solidified to form an integral body, so as to obtain a coupled inductor with a high coupling rate and an internal double-circle magnetic field that offsets each other.
[0019] What needs to be explained in more detail is that the two coils used in the coupled inductor of the utility model can be enameled wires of the same color or different colors, and the enameled wires are classified into round wires, square column wires or flat wires according to the cross-section shape. As can be seen from the preferred embodiment shown in the figure, the enameled wire with a cross-section shape of a square column wire is selected. And in order to facilitate visual distinction and reduce assembly errors, the drum colors of the two coils can be selected differently. The T-shaped magnetic core 3 is cold-pressed from one or a mixture of two or more of Fe-based / FeSiCr / FeNi / FeSiAl / FeSi, and is molded at a pressure of 6~10T / cm² using epoxy resin, silicone resin or acrylic resin. After the preliminary assembly is completed and loaded into the mold, one or a mixture of two or more of Fe-based / FeSiCr / FeNi / FeSiAl can be used, and the resin can be molded at a molding temperature range of 100~200°C and a pressure of 15~25T / cm² for 30~180 seconds to obtain a semi-finished body 4 of the coupled inductor. As shown Figure 3As shown, the semi-finished product is then sprayed with protective paint 5 and dried, and the ends of each column leg are laser stripped to partially expose the metal surface 6; then combined with electroplating treatment, a number of electrode contacts 7 of the coupled inductor are formed.
[0020] In the above two coils, the bent column legs 11 and 12 of the first coil 1 are longer than the bent column legs 21 and 22 of the second coil 2, and the first coil 1 can be optionally superimposed on the upper side of the second coil 2. Based on the fact that the height difference of the two parts of the column legs is close to or equal to the thickness of the enameled wire, the bottom ends of the four column legs are flush, that is, in the final encapsulated mold, the height of the four column legs slightly exposed relative to the bottom surface of the bottom plate is consistent.
[0021] As a preferred configuration, the bottom plate 32 is provided with notches 321 at the four corners, and the four column legs are aligned and connected to the notches in the assembled state, and the gaps between the two are suitable for filling the magnetic powder.
[0022] from Figure 1 As shown, the two coils are combined in a roughly rectangular shape. The bent legs 11 and 12 of the first coil 1 are distributed on one short side of the coupling inductor, and the bent legs 21 and 22 of the second coil 2 are distributed on the other short side of the coupling inductor. Figure 4 As shown in the figure, when the coupled inductor is welded to the PCB board, the two column legs distributed on the corresponding long side serve as current input terminals. When currents i1 and i2 are input to them respectively, the magnetic fields B1 and B2 formed in the corresponding coils will cancel each other out.
[0023] From the above detailed description of the preferred embodiment of the coupled inductor of the utility model, it can be seen that compared with the prior art, the present solution has substantial characteristics and progress, and its technical effect is as follows: the inductor is formed by designing two U-shaped enameled coils that are superimposed and wound together and packaged with a T-shaped magnetic core, such as Figure 5 and Figure 6 As shown, on the one hand, the electric field and magnetic field of the two coils in the inductor can offset each other at a high ratio, which can effectively reduce the electromagnetic interference radiation of the product in practical applications. Ansys maxwell simulation verification shows that the coupled inductor obtained by the structural improvement has a higher coupling rate, and the coupling coefficient K is less than -0.2; on the other hand, optimizing the electrode layout as the current input terminal can effectively save the space occupied by the inductor device in the circuit, which is conducive to the miniaturization of electronic equipment and meets the needs of industrial applications such as artificial intelligence AI, data centers, autonomous driving and smart cities.
[0024] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.
Claims
1. A coupled inductor, which is composed of two coils covered with insulation and a T-shaped magnetic core, and the whole is wrapped with magnetic powder and packaged into one body, characterized in that: Each coil body is formed into a U shape and the open end is bent to one side to form two column legs. The openings of the two coils are in opposite directions and are superimposed and intertwined. The four column legs are in the same direction and form a leakage hole in the middle. The T-shaped magnetic core is integrally formed with a convex column on the bottom plate, and the convex column is connected to the leakage hole in the opposite direction of the column legs. The two coils and the T-shaped magnetic core are assembled with a gap, and the magnetic powder completely wraps the assembly, fills the gap and is packaged and solidified.
2. The coupled inductor according to claim 1, characterized in that: The two coils are enameled wires of the same color or different colors, and the enameled wires are classified into round wires, square column wires or flat wires according to their cross-sectional shapes.
3. The coupled inductor according to claim 1, characterized in that: Of the two coils, the bent column leg of the first coil is longer than the bent column leg of the second coil, the first coil is superimposed on the upper side of the second coil, and the bottom ends of the four column legs are flush.
4. The coupled inductor according to claim 1, characterized in that: The bottom plate is provided with notches at four corners, and the four column legs are aligned and connected to the notches in the assembled state.
5. The coupled inductor according to claim 1, characterized in that: Among the two coils, the bent column legs of the first coil are distributed on one short side of the coupled inductor, and the bent column legs of the second coil are distributed on the other short side of the coupled inductor. When the coupled inductor is welded to the PCB board, the two column legs distributed on the corresponding long side serve as current input terminals.