T-shaped outer expanding wire-wound inductor and manufacturing method thereof

Abstract

The application provides a T-shaped outer expansion wire package inductance and a manufacturing method thereof. The T-shaped outer expansion wire package inductance comprises a T-shaped magnetic core, a base plate and a middle column vertically arranged at the center of the base plate; and a coil wound outside the middle column; wherein the coil is uniformly, layer by layer and closely wound on the outer periphery of the middle column to form a wire package, and the radial width of the wire package is greater than the width of the base plate, so as to cover the middle column in the wire package. The wire package of the T-shaped outer expansion wire package inductance expands outward along the radial direction to cover the middle column, is not limited by the size of the base plate of the magnetic core, can realize high turn number winding, and improves the inductance. The coil is exposed in a large area for heat dissipation, reduces the temperature rise, avoids magnetic saturation, does not need to replace a large magnetic core, has a smaller device volume, and meets the requirements of high inductance, strong heat dissipation and miniaturization.

Description

Technical Field

[0001] This invention relates to the field of electronic components, and more particularly to a T-type externally expanded coil inductor and its manufacturing method. Background Technology

[0002] T-shaped magnetic cores are widely used in various switching power supplies, filter circuits, signal conditioning and small industrial control equipment due to their advantages of simple structure, symmetrical magnetic circuit, low material cost, convenient assembly and stable high-frequency characteristics. They are a common magnetic core structure in the fields of consumer electronics and industrial electrical systems.

[0003] The current industry standard for T-core inductors is to ensure that the winding coil is completely contained within the width of the T-shaped magnetic core chassis and the height of the center post. This means the core dimensions are larger than the coil dimensions, and a low-turns, thick-diameter winding method is commonly used, with the number of turns typically controlled to within a few dozen. The initial intention behind this standard design was to ensure the coil is completely enclosed by the magnetic core, resulting in a compact structure, reduced risk of wire breakage, and compatibility with standardized mass-production winding equipment.

[0004] With the miniaturization of power equipment, the upgrading and iteration of power supply high-precision filtering, weak signal anti-interference, and high-voltage stabilization scenarios, the market's requirements for the inductance, withstand voltage rating, ripple suppression capability, and operational stability of small-volume inductors are continuously increasing. However, existing conventional T-core inductors are limited by the core swing and center column space, making it impossible to achieve high-turn count windings. This results in inherent defects such as low inductance, weak low-frequency filtering capability, insufficient impedance, and poor pulse interference resistance. To achieve high inductance and high withstand voltage performance, traditional technical solutions can only replace the cores with larger-specification cores such as EE, UU, and PQ. Although this can improve parameters, it will significantly increase the device size, occupy more PCB board space, and increase material costs and overall power consumption, failing to meet the comprehensive requirements of small size, high parameters, low cost, and high stability.

[0005] In view of this, it is indeed necessary to improve the existing inductors to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a T-type extended coil inductor based on a small T-type magnetic core, which can achieve high inductance and high stability.

[0007] To achieve the above objectives, the present invention provides a T-type externally expanded coil inductor, comprising: The T-shaped magnetic core includes a chassis and a central column vertically positioned at the center of the chassis. The coil is wound around the outside of the central column; The coil is formed by uniformly, layered and tightly wound around the outer periphery of the central column, and the radial width of the coil is greater than the width of the chassis, so as to cover the central column in the coil.

[0008] Optionally, the chassis is roughly square in shape, and in the radial direction of the coil, the width of the coil extending beyond the edge of the chassis is no more than 1 / 2 of the side length of one side of the chassis.

[0009] Optionally, in the axial direction of the coil, the stacking height of the coils shall not exceed the height of the center post.

[0010] Optionally, the coil is made of a thin wire with a diameter of 0.035mm to 0.12mm.

[0011] Optionally, the number of turns of the coil in the coil is 200 to 500.

[0012] Optionally, the coil surface is provided with an insulating layer with a thickness of 15~30μm.

[0013] Optionally, the coil has lead wires at the beginning and end for connection to the positive and negative electrodes of the T-shaped magnetic core.

[0014] Optionally, the end of the lead wire is fixedly connected to the lower end face of the chassis through a soldering process.

[0015] Optionally, the T-shaped magnetic core can be any one of iron core, ferrite, or alloy; the coil can be any one of copper conductor, aluminum conductor, or alloy conductor.

[0016] The purpose of this invention is to provide a manufacturing method for the above-mentioned T-type extended coil inductor.

[0017] To achieve the above objectives, the present invention provides a method for manufacturing a T-type expanded coil inductor, applicable to the aforementioned T-type expanded coil inductor, comprising the following steps: S1. Select a standardized T-shaped magnetic core as the basic magnetic circuit carrier; S2. The coil is wound on the central column of the T-shaped magnetic core and wound in multiple layers, evenly and tightly to form a coil, wherein the diameter of the coil is 0.035mm~0.12mm; S3. Control the radial stacking width and axial stacking height of the coils so that the axial stacking height of the coils does not exceed the height of the central column and the radial stacking width is greater than the width of the chassis of the T-shaped magnetic core. S4. After the winding is completed, the lead wires at the beginning and end of the coil are fixedly connected to the lower end face of the chassis of the T-shaped magnetic core through a tinning process.

[0018] Compared with the prior art, the beneficial effects of the present invention are: The T-type outward-expanding coil inductor of this invention has its coil expanding outward along its radial direction to cover the central column, which is not limited by the size of the magnetic core chassis, and can achieve high-turn winding to increase inductance; the coil has a large exposed heat dissipation area, reducing temperature rise and avoiding magnetic saturation; there is no need to replace the large magnetic core, the device size is smaller, and it meets the requirements of high inductance, strong heat dissipation and miniaturization. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a T-type externally expanded coil inductor conforming to an embodiment of the present invention; Figure 2 yes Figure 1 The assembly structure diagram of the T-shaped extended coil inductor is shown below; Figure 3 This is a flowchart illustrating the manufacturing method of the T-type extended coil inductor of the present invention.

[0020] Explanation of reference numerals in the attached figures: 100-T type external coil inductor, 110-T type magnetic core, 1101-chassis, 1102-center column, 120-coil, 1201-lead wire. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0023] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0024] like Figure 1 As shown, this invention provides a T-shaped expanded coil inductor 100, the overall structure of which consists of two main parts: a T-shaped magnetic core 110 and a coil 120 formed by winding a coil.

[0025] The T-shaped magnetic core 110 is an integrated sintered structure, comprising a base 1101 and a central column 1102 vertically and integrally formed at the center of the base 1101. The base 1101 has a square overall outline, and the central column 1102 extends vertically upward along the center of the base 1101, serving as the basic carrier for coil winding. The coil is completely wound on the entire outer surface of the central column 1102. The winding process employs a uniform, layered, and tightly fitted winding technique, with multiple layers of wires stacked layer by layer to form a complete and integrated coil 120 structure. The total radial width of the coil 120 is greater than the overall lateral width of the base 1101. The central column 1102 is completely enclosed and contained by the coil 120 formed by multiple layers of coils. The coil extends radially outward to both sides of the base 1101 and is directly exposed to the air, forming a structure where the magnetic core is embedded and the coil 120 is extended and exposed outward, completely different from the traditional closed design where the magnetic core wraps the coil.

[0026] In the radial direction of the coil 120, the width of one side of the coil 120 extending outward beyond the outer edge of the chassis 1101 is no greater than 1 / 2 of the length of one side of the chassis 1101. This setting balances the space requirements for multi-layer winding with the overall mechanical robustness of the coil. If the coil extends outward too much, it will result in an excessively high proportion of coil suspension, which can easily lead to issues such as loosening between coil layers and breakage of the end lead 1201 under stress during transportation or long-term vibration of the entire machine. At the same time, excessive expansion will significantly increase the leakage magnetic field of the coil space, causing electromagnetic interference to precision components on the surrounding PCB board. This dimensional constraint can control the leakage magnetic field within the allowable range of the circuit design, taking into account both heat dissipation improvement and electromagnetic compatibility indicators. In addition, the outward expansion will not increase the overall outer diameter of the components, and can perfectly fit the industry standard surface mount pads, without assembly interference or mounting misalignment issues.

[0027] In the axial stacking direction of the inline package 120, the total height formed by the coil stacking along the vertical direction of the central column 1102 does not exceed the height of the central column 1102 itself. The coil will not extend upward along the upper end of the central column 1102 and will not increase the overall thickness of the device. It can be adapted to the assembly requirements of various ultra-thin power modules and micro precision control circuit boards, which is in line with the development trend of miniaturization and thinning of the whole machine.

[0028] The coil uses fine-diameter wire, with a single wire diameter controlled between 0.035mm and 0.12mm. The fine-diameter wire occupies less winding space per strand, allowing for more layers to be stacked on the limited surface of the 1102 core, thus increasing the total number of turns, which is controlled between 200 and 500 turns. This multi-layered, densely wound structure significantly increases the overall magnetic flux linkage and equivalent impedance of the winding, achieving high inductance output without the need for a larger core. Simultaneously, the overlapping insulation layers of the multiple wires simultaneously improve the overall inter-turn and inter-layer withstand voltage breakdown capability, making it suitable for various circuit scenarios with transient high-voltage pulses.

[0029] Furthermore, a continuous and complete insulating protective layer is uniformly coated on the outer surface of each coil conductor, with the thickness of the insulating coating controlled between 15 and 30 μm. This thickened insulating coating enhances the high-voltage impact resistance of individual conductors, mitigating the risks of core wire breakdown and interlayer leakage. The stacked multi-layer coils further increase the number of insulation protection levels, significantly improving the overall insulation withstand voltage rating. This makes the device less prone to insulation aging and short-circuit failures even during long-term continuous operation in high-voltage fluctuating circuits, thus greatly extending the stable operating life of the device.

[0030] like Figure 1 and Figure 2 As shown, the coil 120 extends outward from its starting and ending points along the winding direction to form two independent leads 1201. These two leads 1201 correspond to the positive and negative electrodes on both sides of the T-shaped magnetic core 110 chassis 1101, respectively, completing the external lead-out of the electrical circuit of the T-shaped extended coil inductor 100. The ends of the two leads 1201 are uniformly bent and attached to the lower plane of the chassis 1101. A standardized high-temperature soldering process is used to complete the fixed connection. Molten solder completely covers the contact surface between the lead ends and the chassis 1101, and after cooling and solidification, an integrated solder layer structure is formed. This solder layer, on the one hand, firmly fixes the leads to the chassis 1101, offsetting the tensile stress on the leads caused by the extended coil 120 and preventing lead breakage and detachment; on the other hand, the solder layer forms flat conductive solder feet, eliminating the need for additional metal terminals and allowing direct mounting and soldering onto PCB pads, simplifying the assembly process, reducing the types of components and materials, and lowering assembly costs.

[0031] In this invention, the T-shaped magnetic core 110 can be freely selected from any one of iron core, ferrite, or alloy according to the product application scenario. For example, nickel-zinc ferrite can be selected for high-frequency weak signal filtering scenarios, iron-silicon-aluminum alloy can be selected for high-current regulated power supply scenarios, and manganese-zinc ferrite can be selected for general low-cost scenarios.

[0032] The conductive core inside the coil can be made of any of the following: copper conductor, aluminum conductor, or alloy conductor. For example, pure copper enameled wire can be used for high-frequency and low-loss requirements, while aluminum enameled wire can be used for low-cost and lightweight requirements. The selection of materials is highly flexible and can be adapted to all types of electrical application scenarios.

[0033] This invention is accompanied by a complete and standardized manufacturing process, which is suitable for the mass automated production of the above-mentioned T-shaped expanded coil inductor 100. The entire process is clear and the technology is mature, and it can be directly implemented and put into production on existing T-shaped expanded coil inductor 100 production lines.

[0034] like Figure 3 As shown, the specific steps are as follows: S1. A standardized T-shaped magnetic core 110 is selected as the basic magnetic circuit carrier.

[0035] Specifically, standard T-shaped magnetic cores 110 with mature, mass-produced square chassis 1101 are procured uniformly from the market, eliminating the need for custom-made cores with special shapes. Simultaneously, insulated fine wires with diameters of 0.035mm to 0.12mm and insulation coating thicknesses of 15μm to 30μm are selected as winding materials. Incoming material inspections of appearance, wire diameter, and insulation thickness are completed in advance, and unqualified materials are rejected.

[0036] S2. The coil is wound on the central post 1102 of the T-shaped magnetic core 110 and then wound in multiple layers, uniformly and tightly to form the coil 120.

[0037] Specifically, the T-shaped magnetic core 110 is fixed inside a dedicated positioning fixture of the automated winding equipment. The equipment is set with a constant and uniform winding tension, and the winding is performed layer by layer along the vertical axis of the central column 1102, with the number of turns in each layer evenly distributed. Throughout the process, problems such as local congestion, multi-layer overlap, and unilateral offset of the wire are avoided. The winding is stopped after stacking 200-500 turns, forming a complete coil 120. During the winding process, the equipment collects the radial stacking dimensions in real time to ensure that the total radial width of the coil 120 is greater than the overall width of the chassis 1101, stably forming an outwardly expanded and exposed structure.

[0038] S3. Control the radial stacking width and axial stacking height of the coil 120 so that the axial stacking height of the coil 120 does not exceed the height of the central column 1102 and the radial stacking width is greater than the width of the chassis 1101 of the T-shaped magnetic core 110.

[0039] Specifically, the axial stacking height of the coils is monitored synchronously throughout the winding process to strictly ensure that the overall height of the coils does not exceed the height of the central column 1102 itself. The single-sided extension width of the coil 120 beyond the edge of the chassis 1101 is monitored synchronously to ensure that this dimension does not exceed half of the single-sided length of the chassis 1101. If the dimensions exceed the tolerance during the winding process, the equipment automatically stops to adjust the spacing of each layer of winding, corrects the error, and then continues winding to ensure that the external dimensions of each product fall within the standard constraint range.

[0040] S4. After the winding is completed, the lead wires 1201 at the beginning and end of the coil 120 are fixedly connected to the lower end face of the chassis 1101 of the T-shaped magnetic core 110 through a tinning process.

[0041] Specifically, after all the winding processes are completed, the excess wires at both ends of the coil 120 are cut off, and the two lead wires 1201 at the start and end are simultaneously bent downwards and attached to the flat end face of the chassis 1101. A tinning process is used to completely wrap the lead wire ends with the contact surface between the lead wire ends and the chassis 1101. After natural cooling, the tin layer solidifies and forms the shape, and the mechanical reinforcement of the lead wires and the PCB soldering conductive pins are formed simultaneously, without the need for secondary processing.

[0042] In summary, the T-shaped extended coil inductor 100 of this invention relies on the open structure of the extended and exposed coil 120, with most of the coil surface in direct contact with the air, ensuring smooth heat dissipation and convection channels. This significantly reduces temperature rise during long-term operation under full load, preventing magnetic saturation, parameter drift, and insulation aging caused by heat accumulation. The densely wound structure with hundreds of turns of fine wire greatly improves inductance and winding impedance, significantly enhancing the suppression of low-frequency ripple, high-frequency noise, and transient pulse spikes, resulting in higher accuracy in weak signal acquisition. The standardized small T-shaped magnetic core 110 eliminates the need to replace it with a larger core, resulting in a smaller overall device size, significantly reduced PCB board space, and lower overall material and production costs. Multiple dimensional constraints combined with end-soldering reinforcement significantly improve the coil's mechanical strength and lead wire tensile strength, enhancing compatibility with automated surface mount assembly. The thickened insulating coating combined with multi-layered insulation significantly improves the overall withstand voltage rating, greatly reducing the risk of breakdown and short-circuit failure under high-voltage conditions, and comprehensively improving the device's long-term continuous operation reliability and lifespan. Meanwhile, the entire manufacturing process relies on existing mature automated equipment, without the need for new special equipment or customized special tooling. The production and debugging are simple, and it is convenient to change production for different specifications of products. The batch production has high consistency and the mass production cost is controllable. It has strong industrialization value and can be widely used in the internal filtering, voltage stabilization and anti-interference circuits of various electrical products such as consumer electronics, industrial control, new energy equipment, and precision instruments.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A T-shaped wire-in-packet inductor, characterized by, include: The T-shaped magnetic core includes a chassis and a central column vertically disposed at the center of the chassis; A coil is wound around the outside of the central column; The coil is formed by uniformly, layeredly, and tightly winding the coil around the outer periphery of the central column, and the radial width of the coil is greater than the width of the chassis, so as to enclose the central column in the coil.

2. The T-shaped overwire bobbin inductor of claim 1, wherein, The chassis is generally square in shape, and in the radial direction of the coil, the width of the coil extending beyond the edge of the chassis is no greater than 1 / 2 of the side length of one side of the chassis.

3. The T-type expanded coil inductor according to claim 1, characterized in that, In the axial direction of the coil, the stacking height of the coils does not exceed the height of the center post.

4. The T-type expanded coil inductor according to claim 1, characterized in that, The coil is a thin wire with a diameter of 0.035mm to 0.12mm.

5. The T-type expanded coil inductor according to claim 1, characterized in that, The coil in the coil has 200 to 500 turns.

6. The T-type expanded coil inductor according to claim 1, characterized in that, The surface of the coil is provided with an insulating layer, the thickness of which is 15~30μm.

7. The T-type expanded coil inductor according to claim 1, characterized in that, The coil has lead wires at its starting and ending points for connection to the positive and negative electrodes of the T-shaped magnetic core.

8. The T-type expanded coil inductor according to claim 7, characterized in that, The end of the lead wire is fixedly connected to the lower end face of the chassis through a tinning process.

9. The T-type expanded coil inductor according to claim 1, characterized in that, The T-shaped magnetic core can be any one of iron core, ferrite, or alloy; the coil can be any one of copper conductor, aluminum conductor, or alloy conductor.

10. A method for manufacturing a T-type expanded coil inductor, applied to the T-type expanded coil inductor according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Select a standardized T-shaped magnetic core as the basic magnetic circuit carrier; S2. The coil is wound on the central column of the T-shaped magnetic core and wound in multiple layers, evenly and tightly to form a coil, wherein the diameter of the coil is 0.035mm~0.12mm; S3. Control the radial stacking width and axial stacking height of the coils so that the axial stacking height of the coils does not exceed the height of the central column and the radial stacking width is greater than the width of the chassis of the T-shaped magnetic core. S4. After the winding is completed, the lead wires at the beginning and end of the coil are fixedly connected to the lower end face of the chassis of the T-shaped magnetic core through a tinning process.

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