Inductor and inductor forming method
By performing a first injection molding process to form the first insulator of the coil and assembling it with the magnetic core, and then performing a second injection molding process to form the second insulator, the problem of low assembly accuracy between the inductor core and the coil is solved, thus ensuring a safe insulation distance and improving the structural strength of the inductor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- EAGLERISE INTELLIGENT DEVICE CORP LTD
- Filing Date
- 2024-11-05
- Publication Date
- 2026-05-08
AI Technical Summary
If the magnetic core and coil of an inductor are not assembled with high precision, the distance between them may not reach the safe insulation distance, which can easily lead to electrical faults.
The coil is first injection molded to form the first insulator, and the magnetic core is positioned and assembled with the first insulator to improve the relative positional accuracy of the coil and the magnetic core. Then, the coil and the magnetic core are fixed by forming the second insulator through a second injection molding to ensure a safe insulation distance.
The assembly precision of the coil and magnetic core has been improved, ensuring that the inductor is less prone to electrical failures, while also reducing the size of the inductor and enhancing its structural strength.
Smart Images
Figure CN122000184A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of inductor technology, and more specifically to an inductor and an inductor forming method. Background Technology
[0002] An inductor is an electronic component that stores magnetic field energy. It functions in various electronic devices, performing functions such as filtering, energy storage, signal processing, and electromagnetic interference suppression. An inductor generally consists of a coil, a magnetic core, and an insulator, with the insulator holding the coil and core in place. In some inductors, during the manufacturing process, the assembly precision between the magnetic core and the coil is not high, resulting in a failure to maintain a safe insulation distance between them. This makes the inductor prone to electrical faults. Summary of the Invention
[0003] This invention primarily addresses the problem of low assembly precision between the magnetic core and coil of inductors, which easily leads to electrical faults.
[0004] According to a first aspect, one embodiment provides an inductor including a coil, a first insulator, a central core, a yoke core, and a second insulator. The first insulator covers the inner circumferential surface of the coil and a portion of the outer circumferential surface and a portion of the end face of the coil. The central core is located inside the coil and is positioned and engaged with the first insulator covering the inner circumferential surface of the coil. The yoke core includes a main body and a protrusion. The protrusion is disposed on the side of the main body near the coil, is located inside the coil, and is positioned and engaged with the first insulator. The end face of the protrusion is abutted against the end face of the central core. The second insulator covers and fixes the coil, the first insulator, the central core, and the yoke core.
[0005] In some embodiments, the cross-sectional area of the protrusion gradually decreases in the direction away from the main body.
[0006] In some embodiments, a first groove is provided on the outer periphery of the central core, the first groove connecting the two ends of the coil, and a second groove is provided on the outer periphery of the yoke core, the second groove communicating with the first groove, and the first groove and the second groove being filled with the second insulator.
[0007] In some embodiments, the first groove extends along the axial direction of the coil.
[0008] In some embodiments, the central core is provided with at least two first grooves, and the first grooves are arranged at intervals on the outer periphery of the central core.
[0009] In some embodiments, the main body of the yoke core is positioned and engaged with a first insulator covering the end face of the coil, a gap is provided between the main body and the end face of the coil, the gap communicates with the first groove and the second groove, and the gap is filled with the second insulator.
[0010] In some embodiments, the inductor includes an insert fixed in the second insulator.
[0011] In some embodiments, at least two coils are provided, and each coil has leads exposed to the first insulator and the second insulator, and the coils are connected in series through the leads.
[0012] In some embodiments, the coil has a heat dissipation surface exposed to the first insulator and the second insulator.
[0013] According to a second aspect, one embodiment provides an inductor forming method based on the inductor described in any of the above embodiments, comprising the following steps:
[0014] The coil is injection molded once to form a first insulator, which covers the inner circumferential surface of the coil and part of the outer circumferential surface and part of the end face of the coil.
[0015] Position and assemble the central core and yoke core with the first insulator;
[0016] The assembled coil, the central core, and the yoke core are subjected to secondary injection molding to form a second insulator, which fixes the coil, the central core, and the yoke core.
[0017] According to the inductor of the above embodiment, the first insulator covers and fixes the coil. The first insulator covering the inner circumference of the coil can be positioned and engaged with the central core. The yoke core is provided with a boss, which can be positioned and engaged with the first insulator. The above configuration improves the assembly accuracy of the coil with the central core and the yoke core, so that there is a sufficient safe insulation distance between the coil and the central core and the yoke core, and the inductor is not prone to electrical failure. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the coil structure of the inductor of the present invention;
[0019] Figure 2 This is a schematic diagram of the structure of the first insulator of the inductor of the present invention;
[0020] Figure 3 This is a schematic diagram of the assembly of the coil and the first insulator of the inductor of the present invention;
[0021] Figure 4 This is a schematic diagram of the structure of the central core and the yoke core of the inductor of the present invention;
[0022] Figure 5 This is a schematic diagram of the structure of the central core of the inductor of the present invention;
[0023] Figure 6 This is a schematic diagram of the structure of the yoke core of the inductor of the present invention;
[0024] Figure 7 This is one of the schematic diagrams showing the assembly relationship of the magnetic core, coil, and first insulator of the inductor of the present invention;
[0025] Figure 8 This is a second schematic diagram showing the assembly relationship of the magnetic core, coil, and first insulator of the inductor of the present invention.
[0026] Figure 9 This is a schematic diagram of the structure of the inductor of the present invention.
[0027] Figure label:
[0028] 1. Coil; 11. Inner circumferential surface; 12. Outer circumferential surface; 13. End face; 14. Lead-out end; 15. Heat dissipation surface; 2. First insulator; 3. Central core; 31. First groove; 4. Yoke core; 41. Main body; 42. Protrusion; 43. Second groove; 5. Second insulator; 6. Gap; 7. Insert. Detailed Implementation
[0029] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.
[0030] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.
[0031] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).
[0032] Inductors are generally formed by injection molding. Specifically, the magnetic core and coil are assembled and placed in a mold. During the assembly process, a certain gap needs to be left between the coil and the magnetic core. Then, plastic fluid is injected into the mold. The plastic fluid can flow into the gap between the coil and the magnetic core. After the plastic cures, it covers and fixes the coil and the magnetic core.
[0033] However, the magnetic core and coil cannot make direct contact during assembly, resulting in low assembly precision. Consequently, in the final inductor, areas between the core and coil may not meet the safe insulation distance, making them prone to electrical faults. To address this, a first insulator can be formed by injection molding the coil. Injection molding produces a high-precision first insulator, allowing the core to be directly positioned and assembled with it, improving the relative positional accuracy between the coil and core. Simultaneously, the thickness of the first insulator can be controlled to meet the minimum safe insulation distance, which helps reduce the inductor's size.
[0034] Based on the first aspect, please refer to Figures 7-9 One embodiment provides an inductor including a coil 1, a first insulator 2, a central core 3, a yoke core 4, and a second insulator 5.
[0035] Please refer to Figures 1-3 The first insulator 2 covers the inner circumferential surface 11 of the coil 1, as well as part of the outer circumferential surface 12 and part of the end face 13 of the coil 1. In this embodiment, two coils 1 are provided, arranged side by side. Correspondingly, two first insulators 2 are also provided, each first insulator 2 corresponding to one coil 1. The first insulator 2 can be made of plastic, and the first insulator 2 is formed by injection molding. After the first insulator 2 is formed, it covers the inner circumferential surface 11, part of the outer circumferential surface 12, and part of the end face 13 of the coil 1.
[0036] Please refer to Figures 4-8The central core 3 is located inside the coil 1, and the central core 3 is positioned and engaged with the first insulator 2 covering the inner circumferential surface 11 of the coil 1. The yoke core 4 includes a main body 41 and a protrusion 42. The protrusion 42 is disposed on the side of the main body 41 near the coil 1, is located inside the coil 1 and is positioned and engaged with the first insulator 2, and the end face of the protrusion 42 is in contact with the end face of the central core 3.
[0037] A central core 3 is disposed inside a coil 1, and a yoke core 4 is disposed at each end of the central core 3. The protrusions 42 disposed on the yoke core 4 can cooperate with the first insulator 2 covering the coil 1 to position the yoke core 4; at the same time, the two protrusions 42 of the two yoke cores 4 respectively fit against the two end faces of the central core 3, which also serve to position the central core 3.
[0038] In the above configuration, the first insulator 2 covering the coil 1 can be positioned and matched with the central core 3 and the yoke core 4, which improves the assembly accuracy of the coil 1 with the central core 3 and the yoke core 4. Sufficient safe insulation distance is left between the coil 1 and the central core 3 and the yoke core 4, so that the inductor is not prone to electrical failure.
[0039] Please refer to Figure 9 The second insulator 5 covers and fixes the coil 1, the first insulator 2, the central core 3, and the yoke core 4. The first insulator 2 is fixed to the coil 1 by a first injection molding. After the central core 3, the yoke core 4, and the first insulator 2 are positioned and assembled, a second injection molding can be performed to form the second insulator 5, which covers and fixes the coil 1, the first insulator 2, the central core 3, and the yoke core 4.
[0040] In some embodiments, please refer to Figure 6 In the direction away from the main body 41, the cross-sectional area of the protrusion 42 gradually decreases. Specifically, the protrusion 42 can be a boss-shaped structure. The aforementioned gradually decreasing cross-sectional area makes the boss form a chamfer-like structure, which facilitates the assembly of the yoke core 4 and the first insulator 2. In addition, in the above configuration, both the yoke core 4 and the central core 3 can be molded by die pressing, which is convenient for mass production.
[0041] In some embodiments, please refer to Figures 4-6The outer periphery of the central core 3 has a first groove 31 that connects the two ends of the coil 1. The outer periphery of the yoke core 4 has a second groove 43 that connects to the first groove 31. Both the first groove 31 and the second groove 43 are filled with a second insulator 5. Specifically, the first groove 31 is located on the side of the central core 3, and the second groove 43 is located on the side of the yoke core 4. After the yoke core 4 is aligned with the central core 3, the first groove 31 and the second groove 43 connect. When the central core 3 and the yoke core 4 are assembled onto the first insulator 2, the first groove 31 and the second groove 43 connect the two ends of the coil 1.
[0042] After the central core 3, yoke core 4, and first insulator 2 are assembled, a second insulator 5 can be formed through secondary injection molding. During the secondary injection molding process, the plastic fluid can flow into the second groove 43 and the first groove 31, thereby fixing the coil 1, first insulator 2, central core 3, and yoke core 4 after curing. The first groove 31 and second groove 43 facilitate the flow of the plastic fluid and ultimately form the second insulator 5 within the first groove 31 and second groove 43, which helps to improve the structural strength of the inductor.
[0043] In some embodiments, please refer to Figure 5 The first groove 31 extends along the axial direction of the coil 1. It is relatively simple to set the first groove 31 extending axially on the central core 3. The central core 3 can be formed by mold pressing, which is convenient for mass production.
[0044] In some embodiments, please refer to Figure 4-6 The central core 3 is provided with at least two first grooves 31, and the first grooves 31 are arranged at intervals on the outer periphery of the central core 3. Specifically, the central core 3 may be provided with two first grooves 31, which are respectively located on two opposite sides of the central core 3. Providing two or more first grooves 31 can promote the flow of plastic fluid during the secondary injection molding process, so that the finally formed second insulator 5 can fully penetrate and cover all parts of the inductor, which is beneficial to improving the structural strength of the inductor.
[0045] In some embodiments, please refer to Figure 7 , Figure 8 The main body 41 of the yoke core 4 is positioned and engaged with the first insulator 2 covering the end face 13 of the coil 1. A gap 6 is provided between the main body 41 and the end face 13 of the coil 1. The gap 6 communicates with the first groove 31 and the second groove 43. The gap 6 is filled with the second insulator 5.
[0046] Since the first insulator 2 only covers part of the end face 13 of the coil 1, a gap 6 remains between the main body 41 of the magnetic core and the end face 13 of the coil 1 after the main body 41 comes into contact with the first insulator 2. During secondary injection molding, the plastic fluid can flow into the second groove 43, the gap 6, and the first groove 31, and solidify to form the second insulator 5. The second insulator 5, located in the gap 6, provides insulation between the yoke magnetic core 4 and the coil 1. At the same time, the second insulator 5 fills the second groove 43, the gap 6, and the first groove 31, improving the structural strength of the inductor.
[0047] In some embodiments, please refer to Figure 9 The inductor includes an insert 7, which is fixed within the second insulator 5. Specifically, the insert 7 includes a nut, a cylindrical post, etc. The insert 7 facilitates the fixing of the inductor during subsequent use.
[0048] In some embodiments, please refer to Figure 1 , Figure 9 At least two coils 1 are provided, and each coil 1 has a lead-out end 14 exposed to the first insulator 2 and the second insulator 5. The coils 1 are connected in series through the lead-out ends 14. In this embodiment, two coils 1 are provided, and the lead-out ends 14 of the two coils 1 are connected by a copper busbar.
[0049] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 9 The coil 1 has a heat dissipation surface 15 exposed to the first insulator 2 and the second insulator 5. The bottom surface of the outer peripheral surface 12 of the coil 1 is not covered by the first insulator 2 and the second insulator 5, forming the heat dissipation surface 15. The inductor can be used in conjunction with a heat dissipation pad or a heat sink to release the generated heat in a timely manner. Specifically, the heat dissipation pad is attached to the heat dissipation surface 15, and the heat sink is located on one side of the heat dissipation surface 15. The heat dissipation pad is used to conduct heat from the inductor to the heat sink, and the heat sink is used to release heat to the external environment.
[0050] According to a second aspect, one embodiment provides an inductor forming method based on an inductor from any of the above embodiments, comprising the following steps:
[0051] The coil 1 is injection molded once to form the first insulator 2. The first insulator 2 covers the inner peripheral surface 11 of the coil 1, as well as part of the outer peripheral surface 12 and part of the end surface 13 of the coil 1.
[0052] When the inductor uses a single coil 1 with a large dimension in the width direction, two or more coils 1 can be placed side by side along the length direction and then connected in series. For inductors with two or more coils 1, the two coils 1 can be injection molded separately once, and after the injection molding is completed, the two coils 1 are placed according to the set positional relationship.
[0053] The central core 3, yoke core 4, and first insulator 2 are positioned and assembled. Specifically, the central core 3 can be first installed inside the coil 1, and then the yoke cores 4 can be installed at both ends of the central core 3. The central core 3 and yoke core 4 can be positioned and fitted with the first insulator 2 covering the coil 1, ensuring the relative positional accuracy between the coil 1 and the core, and reducing the likelihood of insufficient safe insulation distance between the coil 1 and the core.
[0054] The assembled coil 1, center core 3, and yoke core 4 undergo secondary injection molding to form a second insulator 5, which secures the coil 1, center core 3, and yoke core 4. During the secondary injection molding process, inserts such as nuts and cylindrical inserts 7 can be added. Grooves can be provided on the center core 3 and yoke core 4. During secondary injection molding, the plastic fluid can fill these grooves, resulting in a better permeability and coverage of all parts of the inductor after curing, thus increasing the structural strength of the inductor.
[0055] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.
Claims
1. An inductor characterized by, include: A coil and a first insulator, the first insulator covering the inner peripheral surface of the coil and a portion of the outer peripheral surface and a portion of the end face of the coil; A central core is located inside the coil, and the central core is positioned and engaged with the first insulator covering the inner circumferential surface of the coil. The yoke core includes a main body and a protrusion. The protrusion is disposed on the side of the main body near the coil. The protrusion is located inside the coil and is positioned and engaged with the first insulator. The end face of the protrusion is in contact with the end face of the central core. The second insulator covers and fixes the coil, the first insulator, the central core, and the yoke core.
2. The inductor of claim 1, wherein The cross-sectional area of the protrusion gradually decreases in the direction away from the main body.
3. The inductor of claim 1, wherein The outer periphery of the central core is provided with a first groove, which connects the two ends of the coil. The outer periphery of the yoke core is provided with a second groove, which communicates with the first groove. The first groove and the second groove are filled with the second insulator.
4. The inductor of claim 3, wherein, The first groove extends along the axial direction of the coil.
5. The inductor according to claim 3, characterized in that, The central core is provided with at least two first grooves, and the first grooves are arranged at intervals on the outer periphery of the central core.
6. The inductor according to claim 3, characterized in that, The main body of the yoke core is positioned and engaged with the first insulator covering the end face of the coil. A gap is provided between the main body and the end face of the coil. The gap communicates with the first groove and the second groove. The gap is filled with the second insulator.
7. The inductor according to any one of claims 1-6, characterized in that, Includes an insert, which is fixed in the second insulator.
8. The inductor according to any one of claims 1-6, characterized in that, The coil is provided in at least two forms, and the coil has leads exposed to the first insulator and the second insulator. The coils are connected in series through the leads.
9. The inductor according to any one of claims 1-6, characterized in that, The coil has a heat dissipation surface exposed to the first insulator and the second insulator.
10. A method for forming an inductor based on any one of claims 1-9, characterized in that, Includes the following steps: The coil is injection molded once to form a first insulator, which covers the inner circumferential surface of the coil and part of the outer circumferential surface and part of the end face of the coil. Position and assemble the central core and yoke core with the first insulator; The assembled coil, the central core, and the yoke core are subjected to secondary injection molding to form a second insulator, which fixes the coil, the central core, and the yoke core.