E-shaped magnetic core, magnetic device and electronic equipment
By opening notches on the base plate of the E-type magnetic core, the use of materials in areas with less magnetic flux is solved, and the existing magnetic core is designed with a lighter and lower cost is achieved, while improving the heat dissipation performance.
Patent Information
- Application Number
- CN202422363940.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-09-27
AI Technical Summary
The existing magnetic cores are heavier and costly, making it difficult to achieve the goals of higher efficiency, smaller size and lower cost.
An E-type magnetic core is designed, and the bottom plate is provided with a notch along at least one end of the second direction. The notch is located on the side of the central column. Compared with the traditional E-sheet magnetic core, the part on the bottom plate with less magnetic flux is cut off to form a notch to reduce material use, weight and cost.
Without affecting the overall performance of the magnetic core, the use of magnetic core materials is reduced, the weight and cost of magnetic cores are reduced, and the contact area between the PCB winding and air is increased, the heat dissipation performance and the temperature is reduced.
Smart Images
Figure CN222636966U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of magnetic cores, in particular to an E-type magnetic core, a magnetic device and an electronic device. Background Art
[0002] With the progress of the social industrial system, the demand for various electronic devices in various industries is growing day by day. How to make electronic devices more efficient, smaller and cheaper is becoming more and more important. Magnetic devices such as planar transformers and planar inductors are widely used in various electronic devices due to their advantages such as thinness, small size, light weight and high power density. For example, planar transformers are widely used in switching power supplies.
[0003] Magnetic devices usually have planar magnetic cores, such as EE cores, EI cores, EQ cores and other structures. As an important component of magnetic devices, the weight of the planar magnetic core largely determines the weight of the entire magnetic device. The cost of the planar magnetic core accounts for a large proportion of the total cost of the magnetic device. Therefore, how to improve the planar magnetic core and design a lighter and lower-cost planar magnetic core is an urgent problem to be solved in this field. Utility Model Content
[0004] The embodiments of the utility model aim to provide an E-shaped magnetic core, a magnetic device and an electronic device, so as to solve the technical problems of heavy weight and high cost of the magnetic core in the prior art.
[0005] The embodiment of the utility model adopts the following technical solution to solve the above technical problems: an E-shaped magnetic core is provided, comprising:
[0006] Base plate;
[0007] Two side columns, the two side columns are respectively connected to opposite ends of the bottom plate along the first direction;
[0008] A middle column, the middle column is connected to the bottom plate and is located between the two side columns, the middle column and the two side columns are both protruding from the same side of the bottom plate;
[0009] A notch is formed at at least one end of the bottom plate along a second direction, and the notch is located at a side of the center column, wherein the second direction is substantially perpendicular to the first direction.
[0010] In this embodiment, a notch is provided at at least one end of the bottom plate of the E-type magnetic core along the second direction. The notch is provided at a portion of the bottom plate with less magnetic flux. Compared with the traditional E-sheet magnetic core, in this embodiment, the portion of the bottom plate with less magnetic flux at at least one end along the second direction is cut off and a notch is formed, which can reduce the materials used in the E-type magnetic core, reduce the weight of the E-type magnetic core, and reduce the cost of the E-type magnetic core without affecting the overall performance of the E-type magnetic core.
[0011] In some embodiments, the length of the middle column along the first direction is a, the vertical distance between the inner sides of the two side columns is b, the length of the middle column along the second direction is d1, and the length of the bottom plate along the second direction is d2;
[0012] The area of the notch is between (0.05 and 0.15)*(a+b)*(d2-d1).
[0013] In this embodiment, when the area of the gap is between (0.05 and 0.15)*(a+b)*(d2-d1), the cost of the core material can be reduced to a great extent without causing obvious core loss, which helps to achieve a two-way balance between the cost of the core material and the core performance.
[0014] In some embodiments, the area of the gap is between (0.1 and 0.15)*(a+b)*(d2-d1).
[0015] In this embodiment, when the area of the gap is between (0.1 and 0.15)*(a+b)*(d2-d1), the material cost and weight of the magnetic core can be further reduced while ensuring the performance of the magnetic core.
[0016] In some embodiments, the notch is a trapezoidal notch or an arc-shaped notch.
[0017] In this embodiment, the shape of the trapezoidal notch or the arc-shaped notch is roughly compatible with the shape formed by the areas with less magnetic flux at the opposite ends of the bottom plate along the second direction, which can effectively cut off the areas with less magnetic flux in the magnetic core, thereby saving the cost of the magnetic core material to the greatest extent and avoiding the impact on the performance of the magnetic core after cutting.
[0018] In some embodiments, a rounded corner or a chamfer is provided at a junction between a side surface of the bottom plate facing away from the center column and an outer side surface of the side column.
[0019] In this embodiment, the magnetic flux flowing through the junction between the side surface of the bottom plate facing away from the middle column and the outer side surface of the side column is relatively small. After these areas are cut off, the use of materials can be further reduced without affecting the overall performance of the E-type magnetic core, thereby further reducing the cost of the E-type magnetic core.
[0020] In some embodiments, a rounded corner is provided at the junction between a side surface of the bottom plate facing away from the middle column and an outer side surface of the side column;
[0021] The vertical distance between the inner side surfaces of the two side pillars is b, and the vertical distance between the outer side surfaces of the two side pillars is e;
[0022] The radius of the fillet is between (0.1 and 0.5)*(eb).
[0023] In this embodiment, when the radius of the fillet is in the range of (0.1-0.5)*(eb), the cost of the core material can be reduced to a great extent without causing obvious core loss, which helps to achieve a two-way balance between the cost of the core material and the core performance.
[0024] In some embodiments, a groove is formed on a side of the bottom plate facing away from the center column, the groove passes through two opposite ends of the bottom plate along the second direction, and the groove is arranged opposite to the center column.
[0025] In this embodiment, the area of the groove corresponds to the area of the cut-off portion in the region with smaller magnetic flux on the side of the bottom plate away from the center column. After these areas are cut off, the use of materials can be further reduced without affecting the overall performance of the E-type magnetic core, thereby further reducing the cost of the E-type magnetic core.
[0026] In some embodiments, the bottom plate is provided with the notches at two opposite ends along the second direction, and the two notches are respectively located at two opposite ends of the middle column.
[0027] In this embodiment, notches are provided at both opposite ends of the bottom plate along the second direction, which helps to cut off more core volume while ensuring the performance of the core, thereby reducing the weight of the core and the cost of the core.
[0028] Based on the same utility model concept, an embodiment of the utility model further provides a magnetic device, including a first magnetic core, a second magnetic core and a winding, wherein at least one of the first magnetic core and the second magnetic core is the E-type magnetic core described in any of the above embodiments;
[0029] The first magnetic core and the second magnetic core are arranged opposite to each other, the winding is located between the first magnetic core and the second magnetic core, and the winding is wound around the middle column.
[0030] In this embodiment, since the magnetic device includes the E-shaped magnetic core in any of the above embodiments, after the magnetic device adopts the E-shaped magnetic core in any of the above embodiments, the overall weight of the magnetic device can be reduced and the overall cost of the magnetic device can be reduced.
[0031] In some embodiments, the winding is a PCB winding, and a via hole is provided on the PCB winding, and the via hole corresponds to the position of the notch.
[0032] In this embodiment, on the one hand, the via holes on the PCB winding are not covered by the first magnetic core and the second magnetic core. Therefore, it is not necessary to use a relatively expensive resin plugging process due to the contact between the via holes and the first magnetic core and the second magnetic core. The PCB winding can use a relatively low-cost green oil plugging process to seal the via holes, thereby reducing the process cost of the PCB winding.
[0033] On the other hand, the provision of the notch on the bottom plate can increase the contact area between the PCB winding and the air, improve the heat dissipation performance of the PCB winding, and reduce the temperature of the PCB winding.
[0034] Based on the same utility model concept, an embodiment of the utility model further provides an electronic device, including a magnetic device as described in any of the above embodiments.
[0035] In this embodiment, since the electronic device includes the magnetic device in any of the above embodiments, it also has the beneficial effects in the above embodiments, and the specific beneficial effects are not repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.
[0037] Figure 1 It is the top view and side view of the traditional E-sheet magnetic core, where the shaded part in the figure represents the area with relatively less magnetic flux;
[0038] Figure 2 It is a top view of an E-shaped magnetic core in one embodiment of the utility model;
[0039] Figure 3 It is a schematic diagram of the three-dimensional structure of an E-shaped magnetic core in one embodiment of the utility model;
[0040] Figure 4 It is a three-dimensional structural schematic diagram of an E-type magnetic core in another embodiment of the utility model;
[0041] Figure 5 is a coordinate relationship diagram between the core removal ratio and the core loss in the region with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y;
[0042] Figure 6 yes Figure 3 A schematic diagram of the three-dimensional structure of the E-type magnetic core shown in another perspective;
[0043] Figure 7 yes Figure 4 A schematic diagram of the three-dimensional structure of the E-type magnetism from another perspective shown;
[0044] Figure 8 yes Figure 3 Side view of the E-core shown.
[0045] Description of reference numerals:
[0046] 10. E-shaped magnetic core; 11. bottom plate; 12. side column; 13. middle column; 101. notch; 102. fillet; 103. chamfer; 104. groove; X, first direction; Y, second direction. DETAILED DESCRIPTION
[0047] In order to facilitate the understanding of the utility model, the utility model is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly on another element, or there can be one or more centered elements therebetween. The terms "upper", "lower", "left", "right", "upper end", "lower end", "top" and "bottom" used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0048] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.
[0049] Magnetic devices such as planar transformers and planar inductors have been widely used in electronic devices such as switching power supplies in recent years due to their advantages of small size, light weight, and compact structure. Planar magnetic cores are the key components with large volume in magnetic devices. Therefore, how to design planar magnetic cores with higher efficiency, smaller volume, and lower cost is crucial to achieve miniaturization, high power density, and high efficiency of magnetic devices.
[0050] Although the traditional planar magnetic core (such as EE magnetic core, EI magnetic core, EQ magnetic core, etc.) meets the use requirements of electronic devices to a certain extent, the inventors have found that there are still some unevenness in the magnetic flux distribution. Specifically, taking the traditional E-sheet magnetic core as an example, Figure 1 As shown, Figure 1The top view and side view of the traditional E-sheet magnetic core are shown. Since the magnetic flux tends to flow in the path of low magnetic resistance and the magnetic flux loop is always closed in the shortest path, the magnetic flux in the traditional E-sheet magnetic core is mainly concentrated near the side pillars and the middle pillar of the magnetic core. The shaded part in the figure has less magnetic flux passing through. In other words, the bottom of the traditional E-sheet magnetic core has no side pillars on both sides (corresponding to Figure 1 The magnetic flux passing through the areas such as the upper and lower sides of the middle bottom), the junction between the side column and the bottom plate of the core, and the bottom of the middle column is relatively small. This uneven distribution of magnetic flux not only affects the utilization efficiency of the core, but also increases the material cost and weight of the core. In addition, when the winding of the magnetic device is wound with a multi-layer PCB printed board, the via position on the winding is usually close to the middle column of the core, and the via is covered by the core. In order to enhance the insulation performance between the via and the core, a more expensive resin plugging process is usually used, which further increases the overall cost of the magnetic device.
[0051] In order to solve the technical problem of the high overall cost of magnetic devices in the prior art, the embodiment of the utility model provides an E-type magnetic core, a magnetic device and an electronic device, by providing a notch at the end of the bottom plate of the E-type magnetic core along the second direction, providing a fillet or chamfer at the junction of the surface of the side of the bottom plate away from the middle column and the outer side of the side column, and providing a groove on the side of the bottom plate away from the middle column, these notches, fillets or chamfers, and grooves all correspond to the parts with less magnetic flux in the E-type magnetic core. Compared with the traditional E-sheet magnetic core, the parts with less magnetic flux in the E-type magnetic core in this embodiment are cut off, which can reduce the materials used in the E-type magnetic core without affecting the overall performance of the E-type magnetic core, reduce the weight of the E-type magnetic core, and reduce the cost of the E-type magnetic core. In addition, when the E-type magnetic core is used in conjunction with the PCB winding for assembly, the setting of the notch on the bottom plate can increase the contact area between the PCB winding and the air, improve the heat dissipation performance of the PCB winding, and reduce the temperature of the PCB winding. In addition, the vias on the PCB winding can also be exposed through the notch, so there is no need to worry about the vias contacting the E-type core and using a more expensive resin plugging process. As a result, the PCB winding can use a relatively low-cost green oil plugging process to seal the vias, thereby reducing the process cost of the PCB winding and further reducing the overall cost of the magnetic device.
[0052] The following will be combined with the attached Figures 2 to 8 The E-type magnetic core 10, magnetic device and electronic device provided in the embodiment of the utility model are described in detail.
[0053] See also Figure 2 and Figure 3 , Figure 2 1 is a top view of an E-shaped magnetic core 10 in one embodiment of the present invention, wherein X is a first direction, Y is a second direction, Figure 3 It is a perspective view of the E-type magnetic core 10 .
[0054] The embodiment of the utility model provides an E-shaped magnetic core 10, including a bottom plate 11, two side columns 12 and a middle column 13, the two side columns 12 are respectively connected to the opposite ends of the bottom plate 11 along the first direction X, the middle column 13 is connected to the bottom plate 11 and is located between the two side columns 12, the middle column 13 and the two side columns 12 are all protruding from the same side of the bottom plate 11, and a notch 101 is opened at at least one end of the bottom plate 11 along the second direction Y, and the notch 101 is located on the side of the middle column 13, wherein the second direction Y is substantially perpendicular to the first direction X.
[0055] It should be noted that the second direction Y is substantially perpendicular to the first direction X. The second direction Y may be completely perpendicular to the first direction X, or may be substantially perpendicular within an error range in consideration of factors such as processing errors, for example, the angle between the second direction Y and the first direction X is 89°.
[0056] Specifically, the E-type magnetic core 10 can be applied to magnetic devices such as inductors, transformers, and mutual inductors. Figure 2 As shown, for the convenience of explanation, a first direction X and a second direction Y perpendicular to each other are defined in the figure. Optionally, the first direction X may be the length direction of the bottom plate 11 , and the second direction Y may be the width direction of the bottom plate 11 .
[0057] The E-shaped magnetic core 10 may include an integrally formed bottom plate 11, two side columns 12 and a middle column 13, wherein the middle column 13 is located between the two side columns 12, so that the bottom plate 11, the two side columns 12 and the middle column 13 together form an E-shaped magnetic core 10. The middle column 13 may be used to support a winding in a magnetic device, and the winding may be wound on the middle column 13. Optionally, the winding may be a printed circuit board winding (PCB winding), a multi-strand winding or a Litz wire winding, etc.
[0058] like Figure 2 As shown, a notch 101 is provided at at least one end of the bottom plate 11 of the E-type magnetic core 10 along the second direction Y. The notch 101 is provided at a portion of the bottom plate 11 with less magnetic flux. Compared with the traditional E-sheet magnetic core, in this embodiment, the portion of the bottom plate 11 with less magnetic flux along at least one end of the second direction Y is cut off to form the notch 101, which can reduce the materials used in the E-type magnetic core 10, reduce the weight of the E-type magnetic core 10, and reduce the cost of the E-type magnetic core 10 without affecting the overall performance of the E-type magnetic core 10.
[0059] It should be understood that when the E-shaped magnetic core 10 is assembled with the PCB winding, the provision of the notch 101 on the bottom plate 11 can increase the contact area between the PCB winding and the air, improve the heat dissipation performance of the PCB winding, and reduce the temperature of the PCB winding.
[0060] In addition, when the E-type magnetic core 10 is assembled with the PCB winding, the vias on the PCB winding can be exposed through the notch 101, so there is no need to worry about the vias contacting the E-type magnetic core 10 and using a more expensive resin plugging process. As a result, the PCB winding can use a relatively low-cost green oil plugging process to seal the vias, thereby reducing the process cost of the PCB winding and the overall cost of the magnetic device.
[0061] In some embodiments, Figure 2 As shown, notches 101 are provided at opposite ends of the bottom plate 11 along the second direction Y. The two notches 101 are respectively located at opposite ends of the middle column 13, which helps to cut off more core volume while ensuring the overall performance of the core, reduce the weight of the core, and reduce the cost of the core.
[0062] In some embodiments, a cutting machine, a milling machine or other equipment may be used to cut off portions of the bottom plate 11 with less magnetic flux at two opposite ends along the second direction Y to form the notch 101 .
[0063] In other embodiments, the E-shaped magnetic core 10 may also be prepared by die-casting or other methods.
[0064] In some embodiments, before the base plate 11 is cut or die-cast, the position on the base plate 11 with less magnetic flux can be determined by simulation analysis or experiments. For example, the magnetic flux distribution diagram of the E-type magnetic core 10 can be analyzed by simulation software (such as Maxwell simulation software). The magnetic flux distribution diagram can intuitively display the magnetic flux of each part of the E-type magnetic core 10, thereby determining the area with less magnetic flux at the opposite ends of the base plate 11 along the second direction Y.
[0065] In some embodiments, the average magnetic flux density of the E-type magnetic core 10 is T, and the area where the magnetic flux density is lower than a predetermined percentage of T can be defined as an area with smaller magnetic flux. For example, the area where the magnetic flux density is lower than 3%*T at the opposite ends of the base plate 11 along the second direction Y can be defined as an area with less magnetic flux.
[0066] See also Figure 4 and Figure 5 , Figure 4 FIG. 1 is a schematic diagram of the three-dimensional structure of an E-shaped magnetic core 10 in another embodiment of the utility model. Figure 5 The applicant has found through research that the relationship between the core removal ratio and the core loss in the region with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y is a relationship diagram.
[0067] In some embodiments, the shape of the notch 101 can be a trapezoidal notch (see Figure 3 ) or arc notch (see Figure 4The shape of the trapezoidal notch or the arc-shaped notch is roughly matched with the shape formed by the area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y, which can cut off the area with less magnetic flux to the greatest extent, save the cost of the magnetic core material to the greatest extent, and avoid affecting the performance of the magnetic core after cutting.
[0068] The center column 13 can be a square structure (see Figure 3 ), such as a square or rectangular structure, in addition, the middle column 13 can also be other shapes, such as a cylindrical shape (see Figure 4 ). The area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y is a roughly trapezoidal or arc-shaped structure. Therefore, after the area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y is cut off, a roughly trapezoidal gap or an arc-shaped gap is formed. Optionally, the gap 101 is a roughly isosceles trapezoidal gap.
[0069] It is understandable that the present embodiment does not require the shape of the notch 101 to be a very standard trapezoidal structure or arc-shaped structure. For example, in some embodiments, the upper and lower bases of the trapezoidal notch may be straight lines, and the side lines of the trapezoidal notch may be transitioned by arcs.
[0070] like Figure 2 As shown, in some embodiments, the length of the middle column 13 along the first direction X is a (it should be noted that when the middle column 13 is rectangular, a represents the length of the middle column 13 along the first direction X, and when the middle column 13 is cylindrical, a represents the diameter of the middle column 13 along the first direction X), the vertical distance between the inner sides of the two side columns 12 is b, the length of the middle column 13 along the second direction Y is d1, and the length of the bottom plate 11 along the second direction Y is d2; wherein, the area of the notch 101 is between (0.1 and 0.15)*(a+b)*(d2-d1).
[0071] like Figure 2 As shown, the area of the notch 101 is the area of the cut-off portion in the region with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y. When the area of the notch 101 is between (0.05 and 0.15)*(a+b)*(d2-d1), the area of the notch 101 can be
[0072] 0.05*(a+b)*(d2-d1), 0.12*(a+b)*(d2-d1), 0.15*(a+b)*(d2-d1), etc. Within this range, the cost of core materials can be reduced to a great extent without causing obvious core losses, which helps to achieve a two-way balance between core material cost and core performance.
[0073] In specific implementation, the interval where the area of the gap 101 is located can be determined by the following method:
[0074] First, determine the maximum resection area of the area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y. Specifically, the upper bottom resection length has a as the maximum value, the lower bottom resection length has b as the maximum value, and the height has 0.5*(d2-d1) as the maximum value. The connection of the hypotenuse can be a straight line or an arc. This is the maximum resection area, that is, the maximum resection area is 0.25*(a+b)*(d2-d1).
[0075] Then, the optimal resection area interval between 0 and the maximum resection area (corresponding to the area interval of the notch) is determined by simulation analysis or experiment. Specifically, Figure 5 In the figure, it can be seen that when the core cutting ratio is between 20% and 60%, it will not cause a large loss to the core. Therefore, 20% to 60% of the maximum cutting area can be used as the interval where the optimal cutting area is located. In other words, (0.2 to 0.6)*0.25*(a+b)*(d2-d1) can be used as the interval where the optimal cutting area is located. When the cutting area of the area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y is controlled within this interval, both the cost-effectiveness of the core and the overall performance of the core are considered, and a two-way balance between the cost of the core material and the core performance can be achieved. In other words, if too little is cut, it will not be conducive to significantly reducing the cost of the E-type core 10. If too much is cut, it will easily lead to an increase in the core loss. Therefore, in this embodiment, the cutting area of the area with less magnetic flux at the two opposite ends of the bottom plate 11 along the second direction Y is controlled within.
[0076] When the area of the notch 101 is between (0.2 and 0.6)*0.25*(a+b)*(d2-d1), that is, when the area of the notch 101 is between (0.05 and 0.15)*(a+b)*(d2-d1), the cost of the magnetic core can be reduced to a great extent, the weight of the magnetic core can be reduced, and no obvious magnetic core loss will be caused.
[0077] It is understandable that the shape of the cutout notch 101 can be regular or irregular, and the above technical effect can be achieved as long as the area of the notch 101 is in the range of (0.05 to 0.15)*(a+b)*(d2-d1).
[0078] In some embodiments, in order to further reduce the material cost and weight of the magnetic core, the area of the notch 101 may be between (0.1 and 0.15)*(a+b)*(d2-d1).
[0079] like Figure 5As shown, when the core cutting ratio is 40%, the core loss is the lowest, and in the process of gradually increasing the core cutting ratio from 40% to 60%, the core loss increases relatively slowly, and does not lead to a significant increase in the core loss. Therefore, 40% to 60% of the maximum cutting area can be further taken as the interval where the optimal cutting area is located, that is, (0.4 to 0.6)*0.25*(a+b)*(d2-d1)=(0.1 to 0.15)*(a+b)*(d2-d1) can be taken as the interval where the optimal cutting area is located. In this area, while ensuring the core loss, a larger core area can be cut as much as possible, thereby minimizing the core cost and weight.
[0080] It is understandable that, in some embodiments, the optimal resection area may be further determined within the interval where the preferred resection area is located according to actual needs.
[0081] For example, Figure 5 As shown, in order to minimize core loss and improve core performance, 40% of the maximum cut-off area can be taken as the optimal cut-off area.
[0082] See also Figures 6 to 8 , and refer back to Figure 2 , Figure 6 yes Figure 3 The three-dimensional structure diagram of the E-type magnetic core 10 from another perspective is shown. Figure 7 yes Figure 4 The three-dimensional structure diagram of the E-type magnetic 10 from another perspective is shown. Figure 8 yes Figure 3 A side view of the E-type magnetic core 10 is shown.
[0083] In some embodiments, a rounded corner 102 is provided at the junction of the side surface of the bottom plate 11 facing away from the center column 13 and the outer side surface of the side column 12 (see FIG. Figure 6 ) or chamfer 103 (see Figure 7 ).
[0084] The magnetic flux flowing through the junction between the side surface of the bottom plate 11 facing away from the middle column 13 and the outer side surface of the side column 12 is relatively small. Specifically, the magnetic flux distribution diagram of the E-type magnetic core 10 can be obtained through simulation software analysis, so as to determine the area with relatively small magnetic flux at the junction of the side surface of the bottom plate 11 facing away from the middle column 13 and the outer side surface of the side column 12. After cutting off these areas, the use of materials can be further reduced without affecting the overall performance of the E-type magnetic core 10, thereby further reducing the cost of the E-type magnetic core 10.
[0085] The junction between the side surface of the bottom plate 11 facing away from the center column 13 and the outer side surface of the side column 12 can be processed into a rounded corner 102 or a chamfer 103. Figure 6In the embodiment, the intersection of the side surface of the bottom plate 11 away from the center column 13 and the outer side surface of the side column 12 forms a rounded corner 102. Figure 7 In the embodiment, a chamfer 103 is formed at the junction of a surface of the bottom plate 11 facing away from the center column 13 and an outer side surface of the side column 12 .
[0086] In some embodiments, a rounded corner 102 is provided at the junction of the side surface of the bottom plate 11 facing away from the middle column 13 and the outer side surface of the side column 12; the vertical distance between the inner side surfaces of the two side columns 12 is b, the vertical distance between the outer side surfaces of the two side columns 12 is e, and the radius of the rounded corner 102 is between (0.1 and 0.5)*(eb).
[0087] like Figure 2 and Figure 8 As shown, the radius of the fillet 102 may be a quarter arc, and the larger the radius of the fillet 102 is, the larger the cut-off area of the fillet 102 is. When the radius of the fillet 102 is between (0.1 and 0.5)*(eb), for example, the radius of the fillet 102 may be 0.1*(eb),
[0088] 0.3*(eb), 0.5*(eb), etc. Within this range, the cost of core materials can be reduced to a great extent without causing obvious core losses, which helps to achieve a two-way balance between core material cost and core performance.
[0089] In specific implementation, the radius interval of the fillet 102 may be determined in the following manner:
[0090] First, the intersection of the side surface of the bottom plate 11 facing the middle column 13 and the outer side surface of the side column 12 is taken as the center O, and 0.5*(eb) is taken as the radius R, and this is taken as the maximum cut-off area of the fillet 102. Then, the coordinate relationship diagram between the cut-off ratio and the core loss of the fillet 102 can be obtained by simulation analysis or experiment, and then the coordinate relationship diagram between the cut-off ratio and the core loss of the fillet 102 can be analyzed to obtain the range of the optimal cut-off area of the fillet 102 between 0 and the maximum cut-off area. Optionally, when the radius of the fillet 102 is between (0.1 and 0.5)*(eb), the material cost of the core can be reduced to the greatest extent while ensuring the overall performance of the core, and the weight of the core can be reduced.
[0091] like Figure 6 As shown, in some embodiments, a groove 104 is formed on one side of the bottom plate 11 away from the center column 13 . The groove 104 passes through two opposite ends of the bottom plate 11 along the second direction Y, and the groove 104 is disposed opposite to the center column 13 .
[0092] The area of the groove 104 corresponds to the area of the cut-off portion in the region where the magnetic flux is smaller on the side of the base plate 11 away from the center column 13. Specifically, the magnetic flux distribution diagram of the E-type magnetic core 10 can be obtained by simulation software analysis, thereby determining the region where the magnetic flux is smaller on the side of the base plate 11 away from the center column 13. After cutting off these regions, the use of materials can be further reduced without affecting the overall performance of the E-type magnetic core 10, thereby further reducing the cost of the E-type magnetic core 10.
[0093] In some embodiments, the groove 104 is a trapezoidal groove, the shape of which is roughly the same as the shape of the area with smaller magnetic flux on the side of the base plate 11 away from the center column 13, and is relatively easy to process, so as to effectively cut off the area with smaller magnetic flux on the side of the base plate 11 away from the center column 13.
[0094] In some other embodiments, the groove 104 may also be a triangular groove.
[0095] Optionally, the area of the cut trapezoidal groove can be confirmed based on the results of simulation analysis, that is, first define a maximum cut-off area of the cut-off trapezoidal groove, and then obtain a coordinate relationship diagram between the ratio of the cut-off area of the trapezoidal groove to the maximum cut-off area and the core loss through simulation software, and then select a better cut-off size of the trapezoidal groove by analyzing the coordinate relationship diagram.
[0096] The embodiment of the utility model further provides a magnetic device, which may be a transformer, an inductor or other magnetic device.
[0097] The magnetic device includes a first magnetic core, a second magnetic core and a winding, wherein at least one of the first magnetic core and the second magnetic core is the E-type magnetic core 10 in the above embodiment, and the other is adapted to the E-type magnetic core 10. For example, the first magnetic core may be the E-type magnetic core 10, and the second magnetic core may be the I-type magnetic core, the Q-type magnetic core or the E-type magnetic core 10, etc. It is understandable that the other of the first magnetic core and the second magnetic core may also have its portion with a smaller magnetic flux cut off, thereby further reducing the volume and weight of the magnetic device and improving the performance of the magnetic device.
[0098] The first magnetic core and the second magnetic core are arranged opposite to each other, that is, the opening directions of the first magnetic core and the second magnetic core are opposite to each other, and the first magnetic core and the second magnetic core cooperate to form a planar magnetic core structure. The winding is located between the first magnetic core and the second magnetic core, and the winding is wound on the middle column 13.
[0099] Since the magnetic device includes the E-type magnetic core 10 in any of the above embodiments, it also includes the beneficial effects in any of the above embodiments, that is, the magnetic device can reduce the overall weight of the magnetic device and reduce the overall cost of the magnetic device by adopting the E-type magnetic core 10 in any of the above embodiments.
[0100] In some embodiments, the winding adopts PCB winding, and the winding is wound with a multi-layer PCB printed board and installed between the first magnetic core and the second magnetic core. Compared with the traditional wire-wound winding, the PCB winding has a higher degree of integration and a more compact structure, which can improve the structural compactness and space utilization of the magnetic device and reduce the volume of the magnetic device.
[0101] In addition, the provision of the notch 101 on the bottom plate 11 can increase the contact area between the PCB winding and the air, improve the heat dissipation performance of the PCB winding, and reduce the temperature of the PCB winding.
[0102] In some embodiments, a via is opened on the PCB winding, and the via is located near the middle column 13. The position of the via corresponds to the position of the notch 101 on the base plate 11, that is, the via on the PCB winding is not covered by the first magnetic core and the second magnetic core, wherein the PCB winding adopts a green oil plugging process to seal the via.
[0103] Since the vias on the PCB winding are exposed, there is no need to use a relatively expensive resin plugging process because the vias are in contact with the first magnetic core and the second magnetic core. The PCB winding can use a relatively low-cost green oil plugging process to seal the vias, thereby reducing the process cost of the PCB winding and further improving the overall cost-effectiveness of the magnetic device.
[0104] The embodiment of the utility model further provides an electronic device, which includes the magnetic device in the above embodiment and also has the beneficial effects in the above embodiment. Please refer to the above for the specific beneficial effects, which will not be described again here.
[0105] Optionally, the electronic device may be a switching power supply, a household appliance or a communication device.
[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention is described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. An E-type magnetic core, characterized in that: include: Bottom plate (11); Two side columns (12), the two side columns (12) being respectively connected to opposite ends of the bottom plate (11) along a first direction; A middle column (13), the middle column (13) being connected to the bottom plate (11) and being located between the two side columns (12), the middle column (13) and the two side columns (12) being protrudingly disposed on the same side of the bottom plate (11); A notch (101) is provided at at least one end of the bottom plate (11) along a second direction, and the notch (101) is located on the side of the center column (13), wherein the second direction is substantially perpendicular to the first direction.
2. The E-type magnetic core according to claim 1, characterized in that: The length of the middle column (13) along the first direction is a, the vertical distance between the inner sides of the two side columns (12) is b, the length of the middle column (13) along the second direction is d1, and the length of the bottom plate (11) along the second direction is d2; The area of the notch (101) is between (0.05 and 0.15)*(a+b)*(d2-d1).
3. The E-type magnetic core according to claim 2, characterized in that: The area of the notch (101) is between (0.1 and 0.15)*(a+b)*(d2-d1).
4. The E-type magnetic core according to any one of claims 1 to 3, characterized in that: The notch (101) is a trapezoidal notch or an arc-shaped notch.
5. The E-type magnetic core according to claim 1, characterized in that: A rounded corner (102) or a chamfer (103) is provided at the junction between a surface of one side of the bottom plate (11) facing away from the middle column (13) and the outer side surface of the side column (12).
6. The E-type magnetic core according to claim 4, characterized in that: A rounded corner (102) is provided at the junction of a side surface of the bottom plate (11) facing away from the middle column (13) and an outer side surface of the side column (12); The vertical distance between the inner side surfaces of the two side pillars (12) is b, and the vertical distance between the outer side surfaces of the two side pillars (12) is e; The radius of the rounded corner (102) is between (0.1 and 0.5)*(eb).
7. The E-type magnetic core according to claim 1, characterized in that: A groove (104) is provided on one side of the bottom plate (11) away from the middle column (13); the groove (104) passes through two opposite ends of the bottom plate (11) along the second direction, and the groove (104) is arranged opposite to the middle column (13).
8. The E-type magnetic core according to claim 1, characterized in that: The bottom plate (11) is provided with notches (101) at opposite ends along the second direction, and the two notches (101) are respectively located at opposite ends of the middle column (13).
9. A magnetic device, characterized in that: It comprises a first magnetic core, a second magnetic core and a winding, wherein at least one of the first magnetic core and the second magnetic core is the E-type magnetic core according to any one of claims 1 to 8; The first magnetic core and the second magnetic core are arranged opposite to each other, the winding is located between the first magnetic core and the second magnetic core, and the winding is wound around the middle column (13).
10. The magnetic device according to claim 9, characterized in that: The winding is a PCB winding, and a via hole is provided on the PCB winding, and the position of the via hole corresponds to the position of the notch (101).
11. An electronic device, characterized in that: Comprising the magnetic device as claimed in claim 9 or 10.