Inductor, circuit board assembly and household appliance
By using a combination of an arc-shaped first magnetic post and a straight second magnetic post in a differential mode inductor, the problems of limited coil winding turns and severe magnetic leakage were solved, achieving miniaturization and efficient winding of the inductor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GD MIDEA AIR CONDITIONING EQUIP CO LTD
- Filing Date
- 2025-05-19
- Publication Date
- 2026-04-21
AI Technical Summary
The magnetic core design of existing differential mode inductors limits the number of coil turns, occupies a large area, makes them difficult to apply on miniaturized circuit boards, and has serious magnetic leakage.
By using an arc-shaped first magnetic post with straight second magnetic posts at both ends, the coil winding density and uniformity are increased. At the same time, the inductance is increased without increasing the inductance size. Furthermore, the winding efficiency is improved and leakage flux is reduced by utilizing the single axial characteristic of the straight magnetic posts.
Without increasing the inductor's footprint, the inductance was increased, and leakage flux was reduced by optimizing the winding process, thus improving winding efficiency.
Smart Images
Figure CN224153235U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of inductor technology, and more particularly to an inductor, a circuit board assembly, and a household appliance. Background Technology
[0002] Differential-mode inductors are widely used in switching power supply circuits of household appliances due to their high impedance characteristics. In some related technologies, the magnetic core of a differential-mode inductor is toroidal, and the number of turns of the coil depends on the circumference of the inner circle of the coil. The further radially away from the inner circle of the toroid, the sparser the coil arrangement becomes. The magnetic core not covered by the coil has a lower ability to guide magnetic flux compared to the magnetic core covered by the coil, and is more prone to magnetic leakage.
[0003] The number of turns of the coil wound around the toroidal core depends on the circumference of the inner circle of the toroidal core. If you want to increase the number of turns of the coil, you need to increase the circumference of the inner circle of the toroidal core. Then the outer circle of the toroidal core will also increase, thereby increasing the area occupied by the inductor on the circuit board, which is not conducive to the miniaturization design of the circuit board. Utility Model Content
[0004] In view of this, embodiments of this application aim to provide an inductor, a circuit board assembly, and a household appliance, wherein two straight second magnetic pillars are provided at both ends of the arc-shaped first magnetic pillar. The straight magnetic pillars have denser and more uniform windings, which helps to reduce leakage flux while increasing the inductance.
[0005] In a first aspect, embodiments of this application provide an inductor, comprising:
[0006] The magnetic core includes a first magnetic post and two second magnetic posts, the two second magnetic posts being arranged at intervals along a first direction, the two ends of the first magnetic post being connected to the two second magnetic posts, the first magnetic post being arc-shaped, and the second magnetic posts extending along a straight line;
[0007] A single coil is wound around the first magnetic post and the two second magnetic posts;
[0008] Two pins are connected to the two ends of the single coil.
[0009] In some implementations, the first magnetic post is semi-circular.
[0010] In some implementations, the inductor includes a third magnetic post, the two ends of which are connected to the two second magnetic posts, and the first magnetic post, the two second magnetic posts, and the third magnetic post together form a closed-loop magnetic core.
[0011] In some implementations, the third magnetic post is arc-shaped, and the single coil is wound around the third magnetic post.
[0012] In some implementations, the third magnetic post and the first magnetic post are arranged symmetrically.
[0013] In some implementations, the third magnetic post extends in a straight line along the first direction.
[0014] In some implementations, the inductor includes a positioning base, the third magnetic post is disposed on the positioning base, the positioning base has a mounting port, and the pin passes through the mounting port.
[0015] Secondly, embodiments of this application provide a circuit board assembly, including a circuit board and an inductor as described in any embodiment of this application. The circuit board includes a power layer, and the pins are electrically connected to the power layer.
[0016] In some embodiments, the circuit board includes a ground plane that is insulated from the power plane along the thickness direction of the circuit board, and the ground plane is located on the side of the power plane facing the inductor.
[0017] Thirdly, embodiments of this application provide a household appliance, including the circuit board assembly described in any embodiment of this application.
[0018] The inductor provided in this embodiment has two straight second magnetic pillars at both ends of the arc-shaped first magnetic pillar. The straight magnetic pillars have denser and more uniform windings, which helps to reduce leakage flux while increasing the inductance. Simultaneously, the second magnetic pillars do not increase the dimension of the first magnetic pillar along the first direction, that is, they do not increase the dimension of the inductor along the first direction. When the inductor of this embodiment is mounted on a circuit board, and the extension direction of the second magnetic pillars is parallel to the thickness direction of the circuit board, increasing the extension dimension of the second magnetic pillars increases the number of turns of a single coil, increasing the inductance without increasing the area occupied by the inductor on the circuit board.
[0019] Furthermore, the magnetic core provided by this solution allows the winding motion to be decomposed into a simple combination of translational and rotational movements during the winding of a single set of coils, thanks to the single axial characteristic of the linear second magnetic post. This helps improve winding efficiency. When the single set of coils winds to the end of the second magnetic post near the first magnetic post, the single set of coils can also smoothly transition along the connection between the first and second magnetic posts and wind onto the first magnetic post, further improving winding efficiency. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the magnetic core provided in the first embodiment of this application;
[0021] Figure 2 For a single coil wound on Figure 1 The diagram shows the structure of the magnetic core.
[0022] Figure 3This is a schematic diagram of the magnetic core provided in the second embodiment of this application;
[0023] Figure 4 For a single coil wound on Figure 2 The diagram shows the structure of the magnetic core.
[0024] Figure 5 This is a schematic diagram of the structure of the magnetic core disposed on the circuit board according to the second embodiment of this application;
[0025] Figure 6 A schematic diagram of the power layer of a circuit board provided in the third embodiment of this application;
[0026] Figure 7 This is a schematic diagram of the power layer of a circuit board provided in the fourth embodiment of this application.
[0027] Explanation of reference numerals in the attached figures
[0028] 10. Magnetic core; 11. First magnetic column; 12. Second magnetic column; 13. Third magnetic column; 20. Single coil; 30. Power supply layer; 31. Conductive terminal; 32. Wire. Detailed Implementation
[0029] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but should not be used to limit the scope of this application.
[0030] In the description of the embodiments of this application, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0031] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.
[0032] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature and the second feature are in direct contact, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0033] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0034] This application provides an inductor, which includes a magnetic core 10, a single coil 20, and two pins.
[0035] Please see Figure 1 and Figure 3 The magnetic core 10 includes a first magnetic post 11 and two second magnetic posts 12. The two first magnetic posts 11 are arranged at intervals along a first direction, and the two ends of the first magnetic posts 11 are connected to the two second magnetic posts 12.
[0036] For example, the first direction is Figure 1 , Figure 3 , Figure 5 , Figure 6 and Figure 7 The direction indicated by d1 in the middle.
[0037] For example, the first magnetic post 11 is arc-shaped, and the second magnetic post 12 extends in a straight line. That is, the connection between the first magnetic post 11 and the second magnetic post 12 will not form a sharp corner, and the connection between the first magnetic post 11 and the second magnetic post 12 can achieve a smooth transition.
[0038] Please see Figure 2 and Figure 4A single coil 20 is wound around a first magnetic post 11 and two second magnetic posts 12. When the single coil 20 is energized, the magnetic field generated by the coil wound around the first magnetic post 11 is in the direction of the extension of the first magnetic post 11, and the magnetic field generated by the coil wound around the second magnetic posts 12 is in the direction of the extension of the second magnetic posts 12. Since the connection between the first magnetic post 11 and the second magnetic posts 12 does not form a sharp angle, it helps to reduce magnetic flux leakage caused by large turning angles in the magnetic circuit, and helps to reduce inductor leakage flux.
[0039] The inductor provided in this embodiment has two straight second magnetic pillars 12 at both ends of the arc-shaped first magnetic pillar 11. The straight magnetic pillars have denser and more uniform windings, which helps to reduce leakage flux while increasing the inductance. At the same time, the second magnetic pillars 12 do not increase the dimension of the first magnetic pillar 11 along the first direction, that is, they do not increase the dimension of the inductor along the first direction. When the inductor of this embodiment is mounted on the circuit board described below, and the extension direction of the second magnetic pillars 12 is parallel to the thickness direction of the circuit board, increasing the extension dimension of the second magnetic pillars 12 increases the number of turns of a single coil, increasing the inductance without increasing the area occupied by the inductor on the circuit board.
[0040] It should be noted that the area occupied by the inductor on the circuit board refers to the projected area of the inductor on the circuit board.
[0041] Furthermore, during the winding process of a single coil 20, the linear second magnetic post 12 of the magnetic core 10 provided by this solution allows the winding action to be decomposed into a simple combination of translation and rotation, which helps to improve winding efficiency. When the single coil 20 winds to the end of the second magnetic post 12 near the first magnetic post 11, the single coil 20 can also smoothly transition along the connection between the first magnetic post 11 and the second magnetic post 12 and wind onto the first magnetic post 11.
[0042] Two pins are connected to the two ends of a single coil 20 for conductive connection to the power layer 30 of the circuit board described below, so that the power layer 30 provides current to the single coil 20.
[0043] It should be noted that the inductors provided in the embodiments of this application are applicable to differential mode inductors.
[0044] For example, a differential-mode inductor is used in series between the power line and the neutral line in a switching power supply circuit to exhibit high inductive reactance to differential-mode high-frequency interference currents with a phase difference of 180°.
[0045] For example, a single coil 20 may be a flat enameled wire.
[0046] For example, the material of the magnetic core may include at least one of iron-silicon alloy, iron-silicon-aluminum alloy, and magnetic powder core.
[0047] In some embodiments, the first magnetic post 11 is semi-circular. The semi-circular first magnetic post 11 can further increase the smoothness between the first magnetic post 11 and the second magnetic post 12, which helps to further reduce magnetic leakage.
[0048] In some embodiments, the inductor includes a third magnetic post 13, with two second magnetic posts 12 connected to both ends of the third magnetic post 13. The first magnetic post 11, the two second magnetic posts 12, and the third magnetic post 13 enclose a closed-loop magnetic core 10. The closed magnetic core forms a closed magnetic circuit, which helps to reduce magnetic field leakage, improves permeability, and enhances inductance.
[0049] The shape of the third magnetic post 13 is not limited.
[0050] In some embodiments, please combine Figure 1 and Figure 2 The third magnetic post 13 is arc-shaped, and a single coil 20 is wound around the third magnetic post 13. In this way, the connection between the third magnetic post 13 and the second magnetic post 12 can be smoothly transitioned, which helps to reduce the magnetic flux leakage caused by the large turning angle of the magnetic circuit and helps to reduce the leakage magnetic flux of the inductor.
[0051] For example, the third magnetic post 13 and the first magnetic post 11 are arranged symmetrically.
[0052] It should be noted that the second magnetic post 12 has a plane of symmetry, which is perpendicular to the extension direction of the second magnetic post 12. The plane of symmetry divides the second magnetic post 12 into two identical parts. The third magnetic post 13 and the first magnetic post 11 are arranged symmetrically, which means that the third magnetic post 13 and the first magnetic post 11 are arranged symmetrically about the plane of symmetry of the second magnetic post 12.
[0053] In this embodiment, the third magnetic column 13 and the first magnetic column 11 are arranged symmetrically, which helps to make the magnetic field generated by the single coil 20 uniformly distributed, thereby reducing the fluctuation range of magnetic flux density.
[0054] In the embodiment where the first magnetic post 11 is semi-circular, the third magnetic post 13 is also semi-circular.
[0055] In other embodiments, please refer to Figure 3 and Figure 4 The third magnetic post 13 extends in a straight line along the first direction. At this time, the third magnetic post 13 is in a straight line shape. In this embodiment, the third magnetic post 13 is approximately perpendicular to the second magnetic post 12. Since the right-angle transition at the connection between the third magnetic post 13 and the second magnetic post 12 is not conducive to automatic winding, the single coil 20 is not wound around the third magnetic post 13.
[0056] This application provides a circuit board assembly, including a circuit board and an inductor according to any embodiment of this application. The circuit board includes a power layer 30, and pins are electrically connected to the power layer 30.
[0057] For example, the power layer 30 includes two conductive terminals 31, and two pins are respectively connected to the two conductive terminals 31.
[0058] For example, the pin and the conductive terminal 31 can be connected by soldering.
[0059] In the embodiment where the third magnetic post 13 is arc-shaped, a single coil 20 is wound around the first magnetic post 11, two second magnetic posts 12, and the third magnetic post 13. In this embodiment, on the one hand, the closed magnetic core helps to reduce magnetic leakage, and on the other hand, the arc-shaped first magnetic post 11 achieves a smooth transition at the connection between the first magnetic post 11 and the second magnetic post 12, and the arc-shaped third magnetic post 13 achieves a smooth transition at the connection between the third magnetic post 13 and the second magnetic post 12, resulting in a smaller overall magnetic leakage of the inductor.
[0060] In this embodiment, the inductor may or may not be located on the circuit board, as long as the pins are connected to the conductive terminals 31 of the power layer 30.
[0061] In embodiments where the inductor is mounted on a circuit board, the inductor may include a positioning base disposed on the circuit board. One of the first magnetic post 11, the second magnetic post 12, or the third magnetic post 13, around which a single coil 20 is wound, is disposed on the positioning base. The leads pass through the mounting opening to be electrically connected to the power layer 30. That is, the magnetic core is disposed on the circuit board via the positioning base. Alternatively, the inductor may not include a positioning base, and the magnetic core 10 around which the single coil 20 is wound is directly mounted on the circuit board. In this case, it is only necessary to ensure that the part of the inductor other than the leads is insulated from the power layer 30.
[0062] For example, the extension direction of the second magnetic post 12 is parallel to the thickness direction of the circuit board. In this way, the number of turns of a single coil can be increased by increasing the extension dimension of the second magnetic post 12, thereby increasing the inductance without increasing the area occupied by the inductor on the circuit board.
[0063] In an embodiment where the third magnetic post 13 extends linearly along the first direction, a single coil 20 is wound around the first magnetic post 11 and two second magnetic posts 12. In this embodiment, the closed magnetic core helps reduce magnetic leakage, but since the third magnetic post 13 is not covered by the coil, some of the magnetic flux passing through the third magnetic post 13 will leak out through the air, forming magnetic leakage.
[0064] In this embodiment, the third magnetic post 13 needs to be mounted on the circuit board. Thus, when current flows through the wire 32 connected to the conductive terminal 31, a magnetic field is generated. Due to the low magnetic reluctance of the third magnetic post 13, a portion of this magnetic field will inevitably pass through it. The magnetic field generated by the single coil 20 after energization will also pass through the third magnetic post 13. In other words, the third magnetic post 13 becomes a shared magnetic circuit between the magnetic field generated by the energized wire 32 and the magnetic field generated by the energized single coil 20. The magnetic field generated by the energized wire 32 and the magnetic field generated by the energized single coil 20 are coupled, causing the magnetic field to concentrate through the shared magnetic circuit, i.e., the third magnetic post 13, reducing the proportion of magnetic leakage through the air, thereby helping to reduce magnetic leakage.
[0065] The method by which the third magnetic post 13 is mounted on the circuit board is not limited.
[0066] For example, the inductor includes a positioning base, and a third magnetic post 13 is disposed in the positioning base. The third magnetic post 13 is mounted to the circuit board via the positioning base.
[0067] For example, the positioning base has a mounting opening through which the pins pass. This allows the pins to be electrically connected to the conductive terminals 31 on the circuit board.
[0068] Alternatively, the inductor may not include the positioning base, and the third magnetic post 13 may be directly mounted on the circuit board. In this case, it is only necessary to ensure that the third magnetic post 13 is insulated from the power layer 30 and that the third magnetic post 13 does not interfere with the connection between the pin and the conductive terminal 31.
[0069] For example, the wire 32 connected to the conductive terminal 31 can be copper foil, aluminum foil, etc.
[0070] In the embodiment where the third magnetic post 13 is directly mounted on the circuit board, two conductive terminals 31 are respectively located on both sides of the third magnetic post 13 along the first direction, so that the two conductive terminals 31 can be connected to the two pins respectively.
[0071] The wiring method of the wires 32 is not limited. For example, both wires 32 connected to the two conductive terminals 31 extend along a second direction, which is approximately perpendicular to the first direction.
[0072] For example, the second direction is Figure 5 , Figure 6 and Figure 7 The direction indicated by d2 in the diagram.
[0073] For example, such as Figure 7 As shown, in some embodiments, the extension trajectories of the two wires 32 generally overlap, and in this case, the two conductive terminals 31 are spaced apart along the second direction.
[0074] In some other embodiments, such as Figure 6As shown, the extension trajectories of the two wires 32 are parallel to each other and do not overlap. At this time, the two conductive terminals 31 are arranged in an alternating manner.
[0075] It is understandable that the current flowing through the single coil 20 does not need to be limited in the direction of the current in and out. Therefore, there is no corresponding relationship between the two pins and the two conductive terminals 31. It is only necessary to ensure that the two pins are electrically connected to the two conductive terminals 31 respectively.
[0076] In some embodiments, the circuit board includes a ground layer, which is insulated from the power layer 30 along the thickness direction of the circuit board.
[0077] For example, the ground plane is located on the side of the power layer 30 facing the inductor. In this way, the ground plane provides a low-impedance closed loop for the magnetic field energy of the inductor, forcing the magnetic field lines to form a return path along the ground plane, and minimizing the diffusion of magnetic field lines through the ground plane into the power layer 30. This helps to reduce the inductor leakage flux of the inductor to inductive interference to other components of the power layer 30.
[0078] For example, the grounding layer can be a copper foil layer or an aluminum foil layer.
[0079] In the embodiment where the third magnetic post 13 extends linearly along the first direction, the projection of the third magnetic post 13 onto a plane perpendicular to the thickness direction of the circuit board falls within the projection range of the ground layer. This allows the ground layer to better shield the leakage flux of the third magnetic post 13.
[0080] This application provides a household appliance, including a circuit board assembly according to any embodiment of this application.
[0081] For example, circuit board assemblies can be installed in the switching power supply circuits of household appliances.
[0082] Household appliances can include air conditioners, washing machines, refrigerators, etc.
[0083] The various embodiments / implementations provided in this application can be combined with each other without creating contradictions.
[0084] The above description is merely a preferred embodiment of this application and is not intended to limit the 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 spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An inductor, characterized by include: The magnetic core includes a first magnetic post and two second magnetic posts, the two second magnetic posts being arranged at intervals along a first direction, the two ends of the first magnetic post being connected to the two second magnetic posts, the first magnetic post being arc-shaped, and the second magnetic posts extending along a straight line; A single coil is wound around the first magnetic post and the two second magnetic posts; Two pins are connected to the two ends of the single coil.
2. The inductor of claim 1, wherein, The first magnetic post is semi-circular.
3. The inductor of claim 1, wherein, The inductor includes a third magnetic post, the two ends of which are connected to the two second magnetic posts. The first magnetic post, the two second magnetic posts, and the third magnetic post together form a closed-loop magnetic core.
4. The inductor of claim 3, wherein, The third magnetic post is arc-shaped, and the single coil is wound around the third magnetic post.
5. The inductor of claim 4, wherein, The third magnetic column and the first magnetic column are arranged symmetrically.
6. The inductor of claim 3, wherein, The third magnetic post extends in a straight line along the first direction.
7. The inductor of claim 6, wherein, The inductor includes a positioning base, the third magnetic post is disposed on the positioning base, the positioning base has an installation port, and the pin passes through the installation port.
8. A circuit board assembly, characterized by The device includes a circuit board and an inductor as described in any one of claims 1-7, the circuit board including a power layer, and the pins being electrically connected to the power layer.
9. The circuit board assembly of claim 8, wherein, The circuit board includes a ground layer, which is insulated from the power layer along the thickness direction of the circuit board, and the ground layer is located on the side of the power layer facing the inductor.
10. A domestic appliance characterized in that, Includes the circuit board assembly as described in any one of claims 8 or 9.