CN222636966U - E-type magnetic core, magnetic device and electronic equipment - Google Patents

Abstract

The utility model relates to the technical field of magnetic cores, and discloses an E-shaped magnetic core, a magnetic device and electronic equipment, wherein the E-shaped magnetic core, the magnetic device and the electronic equipment comprise a bottom plate, two side posts and a middle post, the two side posts are respectively connected to two opposite ends of the bottom plate along a first direction, the middle post is connected to the bottom plate and is positioned between the two side posts, the middle post and the two side posts are both arranged on the same side of the bottom plate in a protruding mode, at least one end of the bottom plate along a second direction is provided with a notch, and the notch is respectively positioned on the side part of the middle post, wherein the second direction is perpendicular to the first direction. In this embodiment, the notch is formed in a portion of the bottom plate where the magnetic flux is smaller. Compared with the traditional E-piece magnetic core, in the embodiment, the part with less magnetic flux in at least one end of the bottom plate along the second direction is cut off and a notch is formed, so that materials used for the E-type magnetic core can be reduced on the premise that the overall efficiency of the E-type magnetic core is not affected, the weight of the E-type magnetic core is reduced, and the cost of the E-type magnetic core is reduced.

Description

E-type magnetic core, magnetic device and electronic equipment

Technical Field

The present utility model relates to the field of magnetic cores, and in particular, to an E-type magnetic core, a magnetic device, and an electronic apparatus.

Background

With the progress of the social industry system, the current requirements of various industries on various electronic devices are increasingly strong, and how to achieve higher efficiency, smaller volume and lower cost of the electronic devices becomes more important. Magnetic devices such as planar transformers and planar inductors are widely used in various electronic devices due to their light weight, small size, light weight, high power density, and the like, for example, planar transformers are widely used in switching power supplies.

The magnetic device is generally internally provided with a planar magnetic core, such as an EE magnetic core, an EI magnetic core, an EQ magnetic core and the like, wherein the planar magnetic core is an important component of the magnetic device, the weight of the planar magnetic core determines the weight of the whole magnetic device to a great extent, and the cost of the planar magnetic core occupies a larger proportion of the total cost of the magnetic device, so how to improve the planar magnetic core, and design a planar magnetic core with lighter weight and lower cost is a problem to be solved in the field.

Disclosure of utility model

The embodiment of the utility model aims to provide an E-type magnetic core, a magnetic device and electronic equipment, so as to solve the technical problems of heavy weight and high cost of the magnetic core in the prior art.

The embodiment of the utility model adopts the following technical scheme for solving the technical problems that an E-shaped magnetic core is provided, and the E-shaped magnetic core comprises:

a bottom plate;

The two side posts are respectively connected to two opposite ends of the bottom plate along the first direction;

The middle column is connected to the bottom plate and positioned between the two side columns, and the middle column and the two side columns are both arranged on the same side of the bottom plate in a protruding mode;

the bottom plate is provided with a notch along at least one end of the second direction, and the notch is positioned at the side part of the center pillar, wherein the second direction is basically vertical to the first direction.

In this embodiment, a notch is formed at least one end of the bottom plate of the E-shaped magnetic core along the second direction. The notch is arranged at the position with less magnetic flux on the bottom plate. Compared with the traditional E-piece magnetic core, in the embodiment, the part with less magnetic flux in at least one end of the bottom plate along the second direction is cut off and a notch is formed, so that materials used for the E-type magnetic core can be reduced on the premise that the overall efficiency of the E-type magnetic core is not affected, the weight of the E-type magnetic core is reduced, and the cost of the E-type magnetic core is reduced.

In some embodiments, the length of the center pillar in the first direction is a, the vertical distance between the inner side surfaces of the two side pillars is b, the length of the center pillar in the second direction is d1, and the length of the bottom plate in the second direction is d2;

The area of the notch is between (0.05 and 0.15) ×between (a+b) ×between (d 2-d 1).

In this embodiment, when the area of the gap is (0.05-0.15) ×a+b) ×d2-d1, the cost of the magnetic core material can be reduced to a greater extent, no obvious magnetic core loss is caused, and bidirectional balance of the magnetic core material cost and the magnetic core performance is facilitated.

In some embodiments, the area of the notch is between (0.1-0.15) × (a+b) × (d 2-d 1).

In this embodiment, when the area of the gap is (0.1-0.15) × (a+b) ×d2-d1, the material cost and weight of the magnetic core can be further reduced while the performance of the magnetic core is ensured.

In some embodiments, the notch is a trapezoidal notch or an arcuate notch.

In this embodiment, the shape of the trapezoid notch or the arc notch is approximately matched with the shape formed by the areas with smaller magnetic flux in the two opposite ends of the bottom plate along the second direction, so that the area with smaller magnetic flux in the magnetic core can be effectively cut off, the material cost of the magnetic core is saved to a greater extent, and the influence on the performance of the magnetic core after cutting off is avoided.

In some embodiments, a fillet or chamfer is formed at a junction between a side surface of the bottom plate facing away from the center pillar and an outer side surface of the side pillar.

In this embodiment, the magnetic flux flowing through the junction between the side surface of the bottom plate facing away from the center pillar and the outer side surface of the side pillar is smaller, and after these areas are cut off, the material used can be further reduced on the premise that the overall performance of the E-type magnetic core is not affected, so that the cost of the E-type magnetic core is further reduced.

In some embodiments, a fillet is formed at the junction of the side surface of the bottom plate facing away from the center pillar and the outer side surface of the side pillar;

The vertical distance between the inner side surfaces of the two side posts is b, and the vertical distance between the outer side surfaces of the two side posts is e;

the radius of the round angle is (0.1-0.5) ×between (e-b).

In this embodiment, when the radius of the rounded corner is in the interval (0.1-0.5) ×e-b, the cost of the magnetic core material can be reduced to a greater extent, no obvious magnetic core loss is caused, and bidirectional balance of the magnetic core material cost and the magnetic core performance is facilitated.

In some embodiments, a groove is formed in one side, facing away from the center pillar, of the bottom plate, the groove penetrates through two opposite ends of the bottom plate in the second direction, and the groove is opposite to the center pillar.

In this embodiment, the area of the groove corresponds to the area of the cut-out portion in the area where the magnetic flux is smaller on the side of the bottom plate facing away from the center post, and after these areas are cut out, the material used 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.

In some embodiments, the two opposite ends of the bottom plate along the second direction are respectively provided with the notch, and the two notches are respectively positioned at the opposite ends of the center pillar.

In this embodiment, the bottom plate is all offered jaggedly along the relative both ends of second direction, helps cutting off more magnetic core volumes under the prerequisite of guaranteeing magnetic core performance, lightens magnetic core weight, reduces magnetic core cost.

Based on the same inventive concept, the embodiment of the present utility model further provides a magnetic device, including a first magnetic core, a second magnetic core, and a winding, where at least one of the first magnetic core and the second magnetic core is the E-shaped magnetic core according to any one of the above embodiments;

The first magnetic core and the second magnetic core are oppositely arranged, the winding is located between the first magnetic core and the second magnetic core, and the winding is wound on the center post.

In this embodiment, since the magnetic device includes the E-shaped 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 after the magnetic device adopts the E-shaped core in any of the above embodiments.

In some embodiments, the winding is a PCB winding, and a via hole is disposed on the PCB winding, where the via hole corresponds to the position of the notch.

In this embodiment, on the one hand, the via hole on the PCB winding is not covered by the first magnetic core and the second magnetic core, so that the via hole is not required to be in contact with the first magnetic core and the second magnetic core, and a relatively expensive resin plugging process is not required to be used, and the PCB winding can seal the via hole by adopting a green oil plugging process with relatively low process cost, so that the process cost of the PCB winding can be reduced.

On the other hand, the arrangement of the notch on the bottom plate can increase the contact area between the PCB winding and air, improve the heat dissipation performance of the PCB winding and reduce the temperature of the PCB winding.

Based on the same inventive concept, the embodiment of the present utility model further provides an electronic device, including the magnetic device according to any one of the embodiments.

In this embodiment, since the electronic device includes the magnetic device in any of the above embodiments, the electronic device also has the beneficial effects in the above embodiments, and specific beneficial effects are not described again.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.

FIG. 1 is a top view and a side view of a conventional E-piece magnetic core, wherein the shaded portions indicate areas of relatively little magnetic flux;

FIG. 2 is a top view of an E-core in accordance with one embodiment of the present utility model;

FIG. 3 is a schematic perspective view of an E-type magnetic core according to an embodiment of the present utility model;

FIG. 4 is a schematic perspective view of an E-type magnetic core according to another embodiment of the present utility model;

Fig. 5 is a graph showing the coordinate relationship between the core cut-out ratio and the core loss in the areas of the lower magnetic flux in the opposite ends of the bottom plate 11 in the second direction Y;

FIG. 6 is a schematic perspective view of another view of the E-core of FIG. 3;

FIG. 7 is a schematic perspective view of another view of the E-type magnetic device of FIG. 4;

Fig. 8 is a side view of the E-core shown in fig. 3.

Reference numerals illustrate:

10. e-type magnetic core, 11, bottom plate, 12, side posts, 13, middle post, 101, notch, 102, round angle, 103, chamfer, 104, groove, X, first direction, Y, second direction.

Detailed Description

In order that the utility model may be readily understood, a more particular description thereof will be rendered by reference to specific embodiments that are illustrated in the appended drawings. It will be understood that when an element is referred to as being "connected" to another element, it can be directly on the other element or one or more intervening elements may be present therebetween. The terms "upper," "lower," "left," "right," "upper," "lower," "top," and "bottom," and the like, as used herein, refer to an orientation or positional relationship based on that shown in the drawings, merely for convenience in describing the present utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

Magnetic devices such as planar transformers and planar inductors have been widely used in electronic devices such as switching power supplies in recent years because of their small size, light weight, compact structure, and the like. The planar magnetic core is used as a key component with larger volume in the magnetic device, so how to design the planar magnetic core with higher efficiency, smaller volume and lower cost is important to realize miniaturization, high power density and high efficiency of the magnetic device.

Although the conventional planar magnetic core (such as EE magnetic core, EI magnetic core, EQ magnetic core, etc.) satisfies the use requirement of the electronic device to some extent, it has been found through the study of the inventor that there is some non-uniformity in the magnetic flux distribution, specifically, taking the conventional E-piece magnetic core as an example, as shown in fig. 1, fig. 1 shows a top view and a side view of the conventional E-piece magnetic core, because the magnetic flux tends to flow in a path with low magnetic resistance and the magnetic flux circuit always completes the closing with the shortest path, the magnetic flux in the conventional E-piece magnetic core is mainly concentrated near the side posts and the center post, and the magnetic flux passing through the shadow portion in the illustration is less, that is, there is less magnetic flux passing through the area of the bottom non-side post two sides (corresponding to the upper side and the lower side of the bottom in fig. 1), the junction of the side post and the bottom of the center post of the magnetic core, and the non-uniformity in the magnetic flux distribution affects the utilization efficiency of the magnetic core, and increases the material cost and weight of the magnetic core. In addition, when the winding of the magnetic device is wound by using a multi-layer PCB, the via hole on the winding is usually close to the central post of the magnetic core, and the via hole is covered by the magnetic core, so as to enhance the insulation performance between the via hole and the magnetic core, a resin hole plugging process with higher cost is usually used, which further increases the overall cost of the magnetic device.

In order to solve the technical problem of higher overall cost of a magnetic device in the prior art, the embodiment of the utility model provides an E-shaped magnetic core, a magnetic device and electronic equipment, wherein a notch is formed in the end part of a bottom plate of the E-shaped magnetic core along the second direction, a round corner or a chamfer is formed at the junction of the outer side surface of the bottom plate, which is away from a center post, and the outer side surface of the side post, and a groove is formed in the side of the bottom plate, which is away from the center post, wherein the notches, the round corners or the chamfer and the groove correspond to the part with smaller magnetic flux in the E-shaped magnetic core. In addition, when the E-shaped magnetic core is matched with the PCB winding for assembly, the arrangement of the notch on the bottom plate can increase the contact area between the PCB winding and air, improve the heat dissipation performance of the PCB winding and reduce the temperature of the PCB winding. And the through holes on the PCB winding can be exposed through the gaps, so that the problem that the through holes are contacted with the E-shaped magnetic core and an expensive resin plugging process is avoided, and therefore, the PCB winding can seal the through holes by adopting a green oil plugging process with relatively low process cost, and the process cost of the PCB winding can be reduced, and the overall cost of the magnetic device is further reduced.

The E-type magnetic core 10, the magnetic device and the electronic apparatus according to the embodiments of the present utility model will be described in detail with reference to fig. 2 to 8.

Referring to fig. 2 and 3, fig. 2 is a top view of an E-shaped magnetic core 10 according to an embodiment of the utility model, wherein X is a first direction, Y is a second direction, and fig. 3 is a perspective view of the E-shaped magnetic core 10.

The embodiment of the utility model provides an E-shaped magnetic core 10, which comprises a bottom plate 11, two side columns 12 and a middle column 13, wherein the two side columns 12 are respectively connected to two opposite ends of the bottom plate 11 along a first direction X, the middle column 13 is connected to the bottom plate 11 and is positioned between the two side columns 12, the middle column 13 and the two side columns 12 are both convexly arranged on the same side of the bottom plate 11, at least one end of the bottom plate 11 along a second direction Y is provided with a notch 101, the notch 101 is positioned on the side part of the middle column 13, and the second direction Y is basically perpendicular to the first direction X.

The second direction Y may be substantially perpendicular to the first direction X, or may be completely perpendicular to the first direction X, or may be substantially perpendicular within an error range in consideration of the influence of a machining error or the like, for example, an angle between the second direction Y and the first direction X is 89 °.

In particular, the E-type core 10 may be applied to magnetic devices such as inductors, transformers, and the like. As shown in fig. 2, for convenience of explanation, a first direction X and a second direction Y perpendicular to each other are defined in the drawing, alternatively, the first direction X may be a length direction of the base plate 11, and the second direction Y may be a width direction of the base plate 11.

The E-shaped magnetic core 10 may include a bottom plate 11, two side legs 12, and a middle leg 13 integrally formed, wherein the middle leg 13 is located between the two side legs 12, such that the bottom plate 11, the two side legs 12, and the middle leg 13 together form one E-shaped magnetic core 10. The center post 13 may be used to support windings in a magnetic device, which may be wound around the center post 13. Alternatively, the windings may be printed circuit board windings (PCB windings), multi-strand windings or litz wire windings, or the like.

As shown in fig. 2, at least one end of the bottom plate 11 of the E-shaped magnetic core 10 along the second direction Y is provided with a notch 101. The notch 101 is formed in the bottom plate 11 at a position where the magnetic flux is small. Compared with the conventional E-piece core, in this embodiment, the portion of the bottom plate 11 with less magnetic flux in at least one end along the second direction Y is cut off and a notch 101 is formed, so that the material used for the E-type core 10 can be reduced without affecting the overall performance of the E-type core 10, the weight of the E-type core 10 can be reduced, and the cost of the E-type core 10 can be reduced.

It should be appreciated that when the E-shaped magnetic core 10 is assembled with the PCB winding, the arrangement 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.

In addition, when the E-shaped magnetic core 10 is assembled together with the PCB winding, the through holes on the PCB winding can be exposed through the gaps 101, so that the through holes are not required to be in contact with the E-shaped magnetic core 10 to use a more expensive resin hole plugging process, and therefore, the PCB winding can be sealed by adopting a green oil hole plugging process with relatively low process cost, and the process cost of the PCB winding can be reduced, and the overall cost of a magnetic device is reduced.

In some embodiments, as shown in fig. 2, the opposite ends of the bottom plate 11 along the second direction Y are provided with notches 101, and the two notches 101 are respectively located at the opposite ends of the center pillar 13, so that more magnetic core volume can be cut off on the premise of ensuring the overall performance of the magnetic core, the weight of the magnetic core is reduced, and the cost of the magnetic core is reduced.

In some embodiments, a cutting machine, a milling machine, or the like may be used to cut out portions of the opposite ends of the bottom plate 11 in the second direction Y where the magnetic flux is smaller, so as to form the notch 101.

In other embodiments, the E-shaped core 10 may be formed by die casting, etc.

In some embodiments, the location of the lower magnetic flux on the base plate 11 may be determined by simulation analysis or experiment, for example, by analyzing the magnetic flux profile of the E-shaped magnetic core 10 by simulation software (e.g., maxwell simulation software), and the magnetic flux profile may visually display the magnetic flux of each portion of the E-shaped magnetic core 10, so as to determine the region of the lower magnetic flux at the opposite ends of the base plate 11 along the second direction Y.

In some embodiments, the E-type magnetic core 10 has an average magnetic flux density of T, and a region having a magnetic flux density lower than a predetermined percentage of T may be defined as a region having a smaller magnetic flux, for example, a region having a magnetic flux density lower than 3% T in opposite ends of the bottom plate 11 in the second direction Y may be defined as a region having a smaller magnetic flux.

Referring to fig. 4 and 5, fig. 4 is a schematic perspective view of an E-type magnetic core 10 according to still another embodiment of the present utility model, and fig. 5 is a graph of core cut-off ratio versus core loss in regions of lower magnetic flux at opposite ends of a bottom plate 11 along a second direction Y, which has been studied by the applicant.

In some embodiments, the notch 101 may be in the shape of a trapezoidal notch (see fig. 3) or an arcuate notch (see fig. 4). The trapezoid notch or the arc notch is approximately matched with the shape formed by the areas with smaller magnetic flux in the two opposite ends of the bottom plate 11 along the second direction Y, the areas with smaller magnetic flux can be cut off to a large extent, the material cost of the magnetic core is saved to a large extent, and the influence on the performance of the magnetic core after cutting off is avoided.

The center pillar 13 may have a square shape (see fig. 3) such as a square shape or a rectangular shape, and in addition, the center pillar 13 may have other shapes such as a cylindrical shape (see fig. 4). The regions of the bottom plate 11 in which the magnetic fluxes are smaller at the opposite ends in the second direction Y have a substantially trapezoidal or arc-shaped structure, and therefore, substantially trapezoidal or arc-shaped notches are formed after the regions of the bottom plate 11 in which the magnetic fluxes are smaller at the opposite ends in the second direction Y are cut out. Optionally, the notch 101 is a generally isosceles trapezoid notch.

It should be understood that the shape of the notch 101 is not required to be a very standard trapezoid or arc in this embodiment, for example, in some embodiments, the upper and lower bottoms of the trapezoid notch may be straight lines, and the edges of the trapezoid notch may be curved.

As shown in fig. 2, in some embodiments, the length of the middle pillar 13 along the first direction X is a (it should be noted that, when the middle pillar 13 is rectangular, a represents the length of the middle pillar 13 along the first direction X, and when the middle pillar 13 is cylindrical, a represents the diameter of the middle pillar 13 along the first direction X), the vertical distance between the inner sides of the two side pillars 12 is b, the length of the middle pillar 13 along the second direction Y is d1, and the length of the bottom plate 11 along the second direction Y is d2, where the area of the notch 101 is (0.1-0.15) × (a+b) ×between (d 2-d 1).

As shown in fig. 2, the area of the notch 101 is the area of the cut-out portion in the region of the opposite ends of the bottom plate 11 in the second direction Y where the magnetic flux is smaller. When the area of the notch 101 is between (0.05-0.15) × (a+b) × (d 2-d 1), the area of the notch 101 can be

0.05 (A+b) (d 2-d 1), 0.12 (a+b) (d 2-d 1), 0.15 (a+b) (d 2-d 1), etc., in which the core material cost can be reduced to a greater extent without causing significant core loss, which helps to achieve a bidirectional balance of core material cost and core performance.

In specific implementation, the interval in which the area of the notch 101 is located may be determined as follows:

The maximum cut-out area of the region of lower magnetic flux in the opposite ends of the base plate 11 along the second direction Y is first determined, specifically, the upper undercut dividing length is maximized by the value a, the lower undercut dividing length is maximized by the value b, the height is maximized by 0.5 x (d 2-d 1), and the connection of the oblique sides may be straight lines or arcs, which is the maximum cut-out area, that is, the maximum cut-out area is 0.25 x (a+b) x (d 2-d 1).

Then, a section (section corresponding to the area of the notch) where the cutting area is between 0 and the maximum cutting area is determined by simulation analysis or experiments, specifically, as shown in fig. 5, when the cutting ratio of the magnetic core is between 20% and 60%, no larger loss is caused to the magnetic core, so that 20% to 60% of the maximum cutting area can be used as the section where the preferred cutting area is located, that is, (0.2 to 0.6) ×0.25×0.a+b) ×d2-d1 can be used as the section where the preferred cutting area is located, and when the cutting area of the magnetic flux less area in the opposite ends of the bottom plate 11 along the second direction Y is controlled in the section, the cost benefit of the magnetic core is considered, the overall performance of the magnetic core is considered, and the bidirectional balance of the material cost and the performance of the magnetic core can be realized. In other words, if the cutting is too small, it is disadvantageous to significantly reduce the cost of the E-type core 10, and if the cutting is too large, it is likely to cause an increase in core loss, so that in the present embodiment, the cutting area of the areas of the opposite ends of the bottom plate 11 in the second direction Y, where the magnetic flux is small, is controlled to be

When the area of the notch 101 is between (0.05-0.15) × (a+b) × (d 2-d 1), the core cost can be reduced to a greater extent, the weight of the core can be reduced, and no obvious core loss can be caused.

It can be understood that the shape of the cut-out notch 101 may be regular or irregular, and the above technical effect can be achieved only by the area of the notch 101 being in the interval (0.05-0.15) ×a+b) ×d2-d 1.

In some embodiments, to further reduce the material cost and weight of the magnetic core, the area of the notch 101 may be between (0.1-0.15) × (a+b) × (d 2-d 1).

As shown in fig. 5, when the core cutting ratio is 40%, the core loss is the lowest, and in the process that the core cutting ratio gradually increases from 40% to 60%, the core loss increases more gradually, and the core loss does not significantly increase, so that 40% -60% of the maximum cutting area can be further used as the region where the preferred cutting area is located, that is, (0.4-0.6) ×0.25×0.b) = (d 2-d 1) = (0.1-0.15) ×0.1-b) ×d2-d1 is used as the region where the preferred cutting area is located, and in this region, the larger core area can be cut off as much as possible under the premise of ensuring the core loss, thereby reducing the core cost and weight to a greater extent.

It will be appreciated that in some embodiments, the optimal ablation area may be further determined within the interval where the optimal ablation area is located according to actual requirements.

For example, as shown in fig. 5, to minimize core loss and improve core performance, 40% of the maximum cut-out area may be used as the optimal cut-out area.

Referring to fig. 6 to 8, and referring back to fig. 2, fig. 6 is a perspective view of another view of the E-shaped magnetic core 10 shown in fig. 3, fig. 7 is a perspective view of another view of the E-shaped magnetic core 10 shown in fig. 4, and fig. 8 is a side view of the E-shaped magnetic core 10 shown in fig. 3.

In some embodiments, the junction of the side surface of the bottom plate 11 facing away from the center pillar 13 and the outer side surface of the side pillar 12 is provided with a fillet 102 (see fig. 6) or a chamfer 103 (see fig. 7).

The magnetic flux flowing through the junction between the side surface of the bottom plate 11, which is away from the center post 13, and the outer side surface of the side post 12 is smaller, specifically, the magnetic flux distribution diagram of the E-shaped magnetic core 10 can be obtained through analysis of simulation software, so that the region where the magnetic flux is smaller at the junction between the side surface of the bottom plate 11, which is away from the center post 13, and the outer side surface of the side post 12 is determined, after the region is cut off, the use of materials can be further reduced on the premise that the overall performance of the E-shaped magnetic core 10 is not affected, and the cost of the E-shaped magnetic core 10 is further reduced.

The junction of the side surface of the bottom plate 11 facing away from the center pillar 13 and the outer side surface of the side pillar 12 may be rounded 102 or chamfered 103. For example, in fig. 6, a corner 102 is formed at the junction of the side surface of the bottom plate 11 facing away from the center pillar 13 and the outer side surface of the side pillar 12, and in fig. 7, a corner 103 is formed at the junction of the side surface of the bottom plate 11 facing away from the center pillar 13 and the outer side surface of the side pillar 12.

In some embodiments, a fillet 102 is formed at the junction between the outer side surface of the side column 12 and the side surface of the bottom plate 11 facing away from the middle column 13, 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 fillet 102 is (0.1-0.5) ×e-b.

As shown in fig. 2 and 8, the arc of the fillet 102 may be a quarter arc, and the larger the radius of the fillet 102, the larger the cut-out area of the fillet 102. When the radius of the fillet 102 is between (0.1-0.5) (e-b), for example, the radius of the fillet 102 may be 0.1 (e-b),

0.3 (E-b), 0.5 (e-b), etc., in this interval, the core material cost can be reduced to a large extent, no significant core loss can be caused, and the bidirectional balance of the core material cost and the core performance can be realized.

In particular, the interval between the radii of the rounded corners 102 may be determined as follows:

Firstly, taking the intersection point of the side surface of the bottom plate 11 facing the center column 13 and the outer side surface of the side column 12 as a circle center O, taking 0.5 x (e-b) as a radius R, taking the radius as the maximum cutting area of the round corner 102, obtaining a coordinate relation diagram between the cutting proportion of the round corner 102 and the magnetic core loss through a simulation analysis or test mode, and obtaining the section of the round corner 102 between 0 and the maximum cutting area through the coordinate relation diagram between the cutting proportion of the round corner 102 and the magnetic core loss. Optionally, when the radius of the fillet 102 is (0.1-0.5) ×e-b, the material cost of the magnetic core can be reduced to a large extent and the weight of the magnetic core can be reduced while the overall performance of the magnetic core is ensured.

As shown in fig. 6, in some embodiments, a groove 104 is formed on a side of the bottom plate 11 facing away from the center pillar 13, the groove 104 penetrates through opposite ends of the bottom plate 11 along the second direction Y, and the groove 104 is disposed opposite to the center pillar 13.

The area of the groove 104 corresponds to the area of the cut-out portion in the area of the smaller magnetic flux on the side of the bottom plate 11 facing away from the center pillar 13, specifically, the magnetic flux distribution diagram of the E-shaped magnetic core 10 can be obtained through analysis by simulation software, so that the area of the smaller magnetic flux on the side of the bottom plate 11 facing away from the center pillar 13 can be determined, and after the areas are cut out, the use of materials can be further reduced without affecting the overall performance of the E-shaped magnetic core 10, so that the cost of the E-shaped magnetic core 10 can be further reduced.

In some embodiments, the recess 104 is a trapezoidal recess, the shape of which is substantially the same as the shape of the region of lesser magnetic flux in the side of the bottom plate 11 facing away from the center post 13, and the machining is more convenient, so that the region of lesser magnetic flux in the side of the bottom plate 11 facing away from the center post 13 can be effectively cut off.

In other embodiments, the grooves 104 may also be triangular grooves.

Alternatively, the area of the cut-off trapezoidal groove can be confirmed according to the result of simulation analysis, namely, the maximum cut-off area of one cut-off trapezoidal groove is defined first, then a coordinate relation diagram between the ratio of the cut-off area of the trapezoidal groove to the maximum cut-off area and the magnetic core loss is obtained through simulation software, and then the preferable cut-off size of the trapezoidal groove is selected through analysis of the coordinate relation diagram.

The embodiment of the utility model also provides a magnetic device which can be a magnetic device such as a transformer, an inductor and the like.

The magnetic device includes a first magnetic core, a second magnetic core, and a winding, where at least one of the first magnetic core and the second magnetic core is the E-shaped magnetic core 10 in the foregoing embodiment, and the other is adapted to the E-shaped magnetic core 10, for example, the first magnetic core may be the E-shaped magnetic core 10, and the second magnetic core may be the I-shaped magnetic core, the Q-shaped magnetic core, or the E-shaped magnetic core 10. It is understood that the other of the first magnetic core and the second magnetic core may be cut off at a portion with smaller magnetic flux, so as to further reduce the volume and weight of the magnetic device and improve the performance of the magnetic device.

The first magnetic core is opposite to the second magnetic core, namely, the opening directions of the first magnetic core and the second magnetic core are opposite, the first magnetic core and the second magnetic core are matched 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 center pillar 13.

Since the magnetic device includes the E-shaped magnetic core 10 in any of the above embodiments, the beneficial effects of the magnetic device in any of the above embodiments are also included, that is, the overall weight of the magnetic device can be reduced and the overall cost of the magnetic device can be reduced by adopting the E-shaped magnetic core 10 in any of the above embodiments.

In some embodiments, the windings are made of PCB windings, and the windings are wound by multi-layer PCB printed boards and are arranged between the first magnetic core and the second magnetic core.

In addition, the arrangement 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.

In some embodiments, the PCB winding is provided with a via hole near the center pillar 13, and the position of the via hole corresponds to the position of the notch 101 on the bottom plate 11, that is, the via hole on the PCB winding is not covered by the first magnetic core and the second magnetic core, where the PCB winding seals the via hole by adopting a green oil plug hole process.

Because the through holes on the PCB winding are exposed, the more expensive resin plugging process is not needed to be used because the through holes are contacted with the first magnetic core and the second magnetic core, and the PCB winding can seal the through holes by adopting the green oil plugging process with relatively low process cost, so that the process cost of the PCB winding can be reduced, and the overall cost efficiency of the magnetic device is further improved.

The embodiment of the utility model also provides an electronic device, which includes the magnetic device in the above embodiment, and also has the beneficial effects in the above embodiment, and the specific beneficial effects are referred to above and are not repeated herein.

Alternatively, the electronic device may be a switching power supply, a home appliance, a communication device, or the like.

It should finally be noted that the above embodiments are only intended to illustrate the technical solution of the present utility model and not to limit it, that the technical features of the above embodiments or of the different embodiments may be combined in any order, and that many other variations in the different aspects of the present utility model as described above exist, which are not provided in details for the sake of brevity, and that, although the present utility model is described in the detailed description with reference to the foregoing embodiments, it should be understood by those skilled in the art that modifications may be carried out to the technical solution described in the foregoing embodiments or to the equivalent substitution of some of the technical features thereof, where these modifications or substitutions do not depart from the essence of the corresponding technical solution from the scope of the technical solution of the embodiments of the present utility model.

Claims (11)

1. An E-shaped magnetic core, comprising:

A bottom plate (11);

Two side posts (12), wherein the two side posts (12) are respectively connected to two opposite ends of the bottom plate (11) along the first direction;

The middle column (13) is connected to the bottom plate (11) and positioned between the two side columns (12), and the middle column (13) and the two side columns (12) are both arranged on the same side of the bottom plate (11) in a protruding mode;

At least one end of the bottom plate (11) along a second direction is provided with a notch (101), and the notch (101) is positioned at the side part of the center pillar (13), wherein the second direction is basically vertical to the first direction.

2. The E-type magnetic core according to claim 1, characterized in that the length of the center leg (13) in the first direction is a, the vertical distance between the inner side surfaces of the two side legs (12) is b, the length of the center leg (13) in the second direction is d1, and the length of the bottom plate (11) in the second direction is d2;

The area of the notch (101) is between (0.05-0.15) ×a+b) ×d2-d 1.

3. The E-type magnetic core according to claim 2, wherein the area of the notch (101) is between (0.1-0.15) × (a+b) × (d 2-d 1).

4. A E-type magnetic core according to any of claims 1-3, characterized in that the gap (101) is a trapezoidal gap or an arc gap.

5. The E-shaped magnetic core according to claim 1, characterized in that a fillet (102) or a chamfer (103) is provided at the junction of a side surface of the bottom plate (11) facing away from the center pillar (13) and the outer side surface of the side pillar (12).

6. The E-shaped magnetic core according to claim 4, characterized in that a fillet (102) is provided at the junction of the side surface of the bottom plate (11) facing away from the center pillar (13) and the outer side surface of the side pillar (12);

the vertical distance between the inner side surfaces of the two side posts (12) is b, and the vertical distance between the outer side surfaces of the two side posts (12) is e;

The radius of the round angle (102) is (0.1-0.5) ×e-b.

7. The E-shaped magnetic core according to claim 1, characterized in that a groove (104) is provided on a side of the bottom plate (11) facing away from the center pillar (13), the groove (104) penetrates through opposite ends of the bottom plate (11) along the second direction, and the groove (104) is arranged opposite to the center pillar (13).

8. The E-shaped magnetic core according to claim 1, wherein the opposite ends of the bottom plate (11) along the second direction are provided with the notches (101), and the two notches (101) are respectively positioned at the opposite ends of the center pillar (13).

9. A magnetic device comprising a first magnetic core, a second magnetic core, and a winding, at least one of the first magnetic core and the second magnetic core being the E-shaped magnetic core of any one of claims 1-8;

The first magnetic core and the second magnetic core are oppositely arranged, the winding is located between the first magnetic core and the second magnetic core, and the winding is wound on the center pillar (13).

10. A magnetic device according to claim 9, characterized in that the windings are PCB windings provided with vias corresponding to the position of the indentations (101).

11. An electronic device comprising a magnetic device as claimed in claim 9 or 10.