Magnetic Core of Electronic Device

Abstract

The present invention relates to a magnetic core (1) of an electronic device, comprising a middle region (3), a bottom (4a) in the form of a flat plate, and a cover (4b), wherein the middle region (3) is arranged between the bottom (4a) and the cover (4b), wherein a through-opening (2) having a center line (X) is constructed in the middle region (3), wherein a first cross-sectional area (9) of the magnetic core (1) in a first sectional plane (6) is substantially equal to a second cross-sectional area (8) of the magnetic core (1) in a second sectional plane (7), wherein the first sectional plane is parallel to the bottom (4a) and the center line (X) is located in the first sectional plane, and wherein the second sectional plane is perpendicular to the first sectional plane (6) and the center line (X) is located in the second sectional plane, and wherein the bottom (4a) and the cover (4b) protrude beyond the middle region (3) in the direction of the center line (X) on at least two mutually opposite sides.

Description

Technical Field

[0001] The present invention relates to a magnetic core of an electronic device with optimized space utilization and an electronic device comprising such a magnetic core. Background Art

[0002] The use of magnetic cores in power electronic components, for example, for storing electrical energy or filtering interference from power lines, is common. U-shaped or E-shaped magnetic cores, such as those described in DE 3333460 A1, are known. Such magnetic cores typically consume significantly more space than other electronic components, thus significantly contributing to the space requirements of power electronic components. Summary of the Invention

[0003] In contrast, the magnetic core according to the present invention offers the advantage of an optimized geometry with respect to structural space requirements. Here, a high inductance of the magnetic core can be achieved with an overall small height and length of the magnetic core. This is achieved according to the present invention by a magnetic core comprising a middle area, a bottom and a cover. The bottom is constructed in the form of a flat plate. Here, the essentially plate-shaped component is considered to be a flat plate, which has at least one flat upper side, wherein the upper side particularly points in the direction of the middle area. Preferably, the bottom is constructed as a cuboid. However, in principle, other geometric shapes of the bottom are also feasible, for example, it is constructed as a curved plate or as an arch, wherein at least a portion of the upper side of the bottom is flat.

[0004] The middle region is arranged between the bottom and the cover. A through-opening is formed in the middle region, which has a center line. The through-opening is especially formed completely in the middle region. Preferably, the through-opening has a rectangular or square cross-section.

[0005] The first cross-sectional area of the central region in the first sectional plane is essentially equal to the second cross-sectional area of the magnetic core in the second sectional plane. The first sectional plane is parallel to the base and is arranged so that the center line lies in the first sectional plane. Therefore, half of the first cross-sectional area corresponds to the magnetic cross-sectional area of the central region. The second sectional plane is perpendicular to the first sectional plane and is likewise arranged so that the center line lies in the second sectional plane. Thus, half of the second cross-sectional area corresponds to the magnetic cross-sectional area of the base and the cover. The size of these first and second cross-sectional areas, and thus the size of the magnetic cross-sectional area, is decisive for the inductance of the magnetic core. Preferably, the first and second cross-sectional areas are exactly the same size.

[0006] Furthermore, the base and cover protrude beyond the central region along the centerline on at least two opposing sides. In other words, a first length of the central region of the magnetic core along the centerline is less than a second length of the corresponding base and cover along the centerline. This means, for example, that the base and cover each form a kind of ceiling that protrudes beyond the central region. This allows for a particularly compact geometry of the magnetic core, particularly in the central region, wherein the first cross-sectional area, which is substantially equal to the second cross-sectional area, ensures a high, desired inductance of the magnetic core. The smaller axial length of the central region allows for a particularly compact geometry of the magnetic core. This provides more space for additional components. For example, electronic components, such as capacitors, can be arranged very close to the central region, preferably below the ceiling formed by the base and cover. This allows the length of the magnetic core or a component using the magnetic core to be shortened while maintaining the height of the component. This is particularly advantageous if, for example, a printed circuit board is arranged in the through-opening. Furthermore, designing the base and cover so that they protrude in the direction of the centerline offers the advantage that the base and cover can each have smaller dimensions along the Z axis, perpendicular to the first sectional plane, while nonetheless ensuring the required size of the first cross-sectional area. This allows a magnetic core with high inductance to be provided while maintaining a particularly small overall height along the Z axis. This means that the special geometry of the magnetic core particularly allows the length of the magnetic core in the central region to be shortened while maintaining the inductance, without having to increase the overall height. To ensure the required cross-sectional area of the central region in the first sectional plane, the central region can be widened, for example, in the transverse direction.

[0007] Preferred developments of the invention are the subject matter of the dependent claims.

[0008] Preferably, the magnetic core is formed of a material having ferrite and / or iron powder material. Such a magnetic core is produced, for example, by sintering or extrusion, in particular in a mold, thereby enabling particularly simple and cost-effective production with flexible shaping.

[0009] The base and the cover preferably each protrude by at least 5%, preferably by at least 10%, particularly preferably by a maximum of 50% of the length of the central region, in order to achieve a particularly compact geometry of the magnetic core with respect to the longitudinal extension of the central region.

[0010] Particularly preferably, the intermediate region has a first height in a direction perpendicular to the bottom, where the first height is at least 10%, preferably at least 20%, preferably at most 40% and particularly preferably 30% of the total height of the magnetic core in the direction perpendicular to the bottom. This ensures an optimal geometry of the magnetic core with respect to the height of the magnetic core, in particular in order to achieve a smaller total height in the case of a high desired inductance and sufficient space for additional electronic components.

[0011] Preferably, the bottom and the cover protrude beyond the intermediate region on both sides in the direction of the center line. Particularly preferably, the bottom and the cover protrude beyond the intermediate region symmetrically here, that is to say, the magnetic core preferably has a symmetric geometry with respect to a transverse plane perpendicular to the center line. When viewed laterally, the magnetic core has a T shape here. This enables a uniform distribution of the magnetic flux density and the magnetic field strength in addition to a particularly compact geometry.

[0012] Furthermore, it is preferred that the through-opening extends from the bottom to the cover. That is to say, the through-opening particularly divides the intermediate region into two separate regions. Preferably, the intermediate region thus includes a first wall and a second wall. The two walls are arranged, for example, at a predefined distance from the center line respectively. The walls can have any cross-section. Particularly preferably, each of the walls has a rectangular cross-section. This enables the magnetic core to be manufactured particularly simply and inexpensively.

[0013] Preferably, the bottom and the cover are formed in the form of two square plates. Preferably, the two plates have the same geometry. As an alternative, the two plates can also have different geometries, for example different widths, as long as the cross-sectional area remains the same. Preferably, the two plates are arranged parallel to each other and particularly perpendicular to the two walls. This enables the magnetic core to be manufactured particularly simply and enables a large magnetic cross-sectional area in the region of the bottom and the cover.

[0014] The magnetic core is advantageously formed in two parts. Preferably, the bottom is provided separately from the intermediate region here, and the intermediate region is particularly formed integrally with the cover. Preferably, the bottom and the intermediate region can be connected to each other, for example, by means of an adhesive connection or by means of a plug connection, where the plug connection can be particularly achieved by means of a plug element formed of plastic, and the bottom and the intermediate region are inserted into the plug element. As an alternative, the bottom and the intermediate region can be not connected. By the two-part construction of the magnetic core, the magnetic core can be manufactured particularly simply and inexpensively, and in particular, the installation in an electronic device can also be simplified, for example, in such a way that the magnetic core can be installed around a printed circuit board.

[0015] Preferably, a gap, preferably an air gap, is formed between the middle area and the bottom. That is, the magnetic core consists of two separate parts, which are arranged relative to each other at a predefined minimum distance, so that the gap is formed between the two parts. The first part comprises the middle area and the cover, wherein the middle area and the cover are preferably constructed integrally with each other. The second part of the magnetic core is preferably the bottom, which is arranged in such a way that the gap is present between the bottom and the middle area. The design with the gap makes it possible to prevent core saturation in the event of high currents. Preferably, the magnetic core includes a distance keeper to ensure the gap between the two parts of the magnetic core. The distance keeper is preferably formed from a non-magnetic material, such as plastic. For example, the two parts can be connected to each other by means of a plug-in connection by means of a plug-in element, wherein in particular the plug-in element forms the distance keeper.

[0016] Particularly preferably, the middle region, the bottom and the cover are formed in one piece, that is to say, when viewed in the direction of the center line, a one-piece, substantially O-shaped and closed magnetic core in the circumferential direction is produced, in particular without gaps.

[0017] The magnetic core preferably includes two intermediate regions, each having a through-opening. The two intermediate regions are arranged directly adjacent to one another in a direction perpendicular to the second sectional plane. The two through-openings are preferably parallel to one another. The magnetic core is thus particularly E-shaped. For example, a portion of a printed circuit board can be arranged in each of the two through-openings. The two intermediate regions are preferably integrally formed, that is, an intermediate wall is preferably arranged between the two through-openings, the intermediate wall being formed, in particular, by two adjacent walls of the two intermediate regions. The intermediate wall thus preferably has a cross-sectional area that is twice that of one of the walls of the intermediate regions. In particular, for a magnetic core having two intermediate regions, the first cross-sectional area of each intermediate region is considered separately. That is, each of the two intermediate regions has a first cross-sectional area that is substantially equal to the second cross-sectional area in the second sectional plane. A gap is particularly preferably provided between the intermediate wall and the base, wherein, in particular, the outer walls each abut the base without a gap. Alternatively, a gap can also preferably be provided between the outer walls and the base.

[0018] Furthermore, the present invention relates to an electronic device, which includes the magnetic core and the printed circuit board described above. For example, the electronic device can be a power electronic component, especially for use in a vehicle, such as in a vehicle controller. The printed circuit board passes through the through-opening of the magnetic core and is arranged parallel to the bottom of the magnetic core. Thus, the magnetic core can especially achieve current smoothing or filter interference from the power supply line during the operation of the electronic device. Preferably, the electronic device can further include a housing, inside which the printed circuit board and the magnetic core are arranged.

[0019] Preferably, the electronic device further includes at least one electronic component arranged on the printed circuit board. The electronic component is arranged in such a way that it is at least partially covered by the bottom and the cover of the magnetic core, whereby the electronic device is kept particularly compact. That is to say, the electronic component is preferably at least partially arranged inside the space defined by the cover and the bottom. The electronic component can be, for example, a capacitor or other surface-mounted components (also known as surface mounted device, abbreviated as SMD). Due to the special geometry of the magnetic core and the shortened axial length in the area of the printed circuit board, a particularly small size of the electronic device can be achieved especially in the direction of the center line, while the total height of the magnetic core and the electronic device can be maintained. Therefore, preferably, the electronic device is suitable for applications with limited structural space, such as vehicle controllers. Description of the Drawings

[0020] The present invention will be described below with reference to embodiments in conjunction with the drawings. Components with the same functions are denoted by the same reference numerals in the drawings. Here:

[0021] Figure 1 A perspective view of an electronic device with a magnetic core according to the first embodiment of the present invention is shown,

[0022] Figure 2 It shows Figure 1 a cross-sectional view of

[0023] Figure 3 It shows Figure 1 another cross-sectional view of

[0024] Figure 4 An electronic device with a magnetic core according to the second embodiment of the present invention is shown, and

[0025] Figure 5 An electronic device with a magnetic core according to the third embodiment of the present invention is shown. Detailed Description of the Embodiments

[0026] Figures 1 to 3An electronic device 10 having a magnetic core 1 according to a first embodiment of the present invention is shown. For orientation, an X-axis, a Y-axis, and a Z-axis are depicted perpendicular to each other.

[0027] Figure 1 A perspective view of the electronic device 10 is shown herein. Figure 2 Shown is Figure 1 a cross-sectional view, wherein a second cutting plane 7 is defined by the X-axis and the Z-axis. Figure 3 Shown is Figure 1 another cross-sectional view together with an alternative first cutting plane 6, which is defined by the X-axis and the Y-axis. For illustration, in Figure 1 a first cutting line 6' corresponding to the section in the first cutting plane 6 and a second cutting line 7' corresponding to the section in the second cutting plane 7 are respectively marked at the magnetic core 1 with dashed lines.

[0028] The electronic device 10 is particularly arranged inside a housing, wherein a housing bottom 11 of the housing is schematically outlined in Figures 1 to 3 ...

[0029] The electronic device 10 includes a magnetic core 1 and a printed circuit board 20. The printed circuit board 20 extends along the X-axis and is particularly arranged in a first cutting plane 6 defined by the X-axis and the Y-axis. The magnetic core 1 has a through-opening 2 having a center line X, wherein the center line X corresponds to the X-axis. The printed circuit board 20 extends through the through-opening 2.

[0030] The through-opening 2 has a rectangular cross-section and is formed in an intermediate region 3 of the magnetic core 1. Specifically, the through-opening 2 divides the intermediate region 3 into two separate walls 31, 32, as can be seen particularly in Figure 3 ... Figure 2 The two walls 31, 32 are preferably connected to each other by a connecting region 49, as can be seen in

[0031] ... for example, in order to optimally utilize the available structural space and / or to facilitate manufacturing.

[0032] Furthermore, the magnetic core 1 has a bottom 4a and a cover 4b, which are respectively configured as substantially square flat plates. The intermediate region 3 is arranged between the bottom 4a and the cover 4b, particularly along the direction of the Z-axis. Here, the cover 4b and the intermediate region 3 are integrally formed, resulting in a U-shaped overall structure when viewed along the direction of the center line X.

[0033] The bottom 4a and the intermediate region 3 are arranged directly adjacent to each other, that is, without a gap.

[0034] As can be seen in Figure 1 the intermediate region 3 and the cover 4b have the same second width 70 along the direction of the Y-axis. The first width 42 of the bottom 4a is slightly larger here, but as an alternative, it can also be equal to the second width 70.

[0035] Along the direction of the X-axis, the intermediate region 3 has a different first length 30 compared to the bottom 4a and the cover 4b. The first length 30 of the intermediate region 3 is 30% smaller than the second length 40 of the corresponding bottom 4a and cover 4b. The intermediate region 3, the bottom 4a, and the cover 4b are arranged such that the bottom 4a and the cover 4b protrude beyond the intermediate region 3 along the direction of the center line X, similar to a ceiling.

[0036] Therefore, the magnetic core 1 shortened in the region of the intermediate region 3 provides a larger supply of position space to be able to fix electronic components 60, such as capacitors or other surface-mounted components, on the printed circuit board 20. Such electronic components 60 are generally significantly smaller than the magnetic core 1, so that these electronic components can be arranged on the printed circuit board 20 such that these electronic components are at least partially covered by the bottom 4a and the cover 4b. That is, the electronic components 60 are at least partially arranged inside the space defined by the bottom 4a and the cover 4b in this case. Thereby, a particularly space-saving overall structural size of the electronic device 10 can be achieved, which is particularly advantageous in applications, such as in the controller of a motor vehicle, where there is usually a very limited supply of position space. Particularly along the direction of the center line and / or the Z-axis, the structural space is usually limited here, and the special structure having the intermediate region 3, the bottom 4a, and the cover 4b can achieve the best utilization of the space and thus enable a high inductance of the particularly compact magnetic core 1.

[0037] For an optimized supply of position space for the electronic components 60 on the printed circuit board, it is particularly advantageous that the first height 35 of the intermediate region 3 is approximately 30% of the total height 50 of the magnetic core 1 (see Figure 2). In particular, this makes it possible to achieve a very low overall height of the magnetic core, wherein, as described below, optimal magnetic properties are ensured by the special geometry of the magnetic core 1 .

[0038] The magnetic core 1 is specifically designed so that, despite its extremely compact geometry, it has a very high inductance in order to ensure high efficiency, for example, for filtering electrical and / or magnetic interference. To this end, the central region 3, the base 4a, and the cover 4b are designed so that the same cross-sectional areas 8, 9 are present, respectively, which optimally utilize the available installation space.

[0039] Here, the second cross-sectional area 8 corresponds to the second section plane 7 defined by the X-axis and the Z-axis. Figure 2 That is, the second cross-sectional area 8 corresponds to the sum of the two cross-sectional areas 81 and 82 of the bottom 4a and the cover 4b. The two cross-sectional areas 81 and 82 of the bottom 4a and the cover 4b correspond to the magnetic cross-sectional area of the cover 4b or the bottom 4a, respectively.

[0040] Furthermore, the first cross-sectional area 9 corresponds to the first section plane 6 in the Figure 3 That is, the first cross-sectional area 9 corresponds to the sum of the two cross-sectional areas 91 and 92 of the two walls 31 and 32. The two cross-sectional areas 91 and 92 of the two walls 31 and 32 correspond to the magnetic cross-sectional area of the intermediate region 3 respectively.

[0041] Figure 4 An electronic device 10 is shown having a magnetic core 1 according to a second exemplary embodiment of the present invention. The second exemplary embodiment corresponds essentially to Figures 1 to 3 A first embodiment of the present invention is described, the difference being that the cover 4b has a larger second axial length 40′ and a gap 15 is formed between the middle region 3 and the bottom 4a. The second axial length 40′ is at least 10% greater than the first axial length 40 of the bottom 4a. This allows the overall height 50 of the magnetic core 1 to be further reduced by reducing the height 48 of the cover 4b compared to the first embodiment. However, the longer cover 4b in the direction of the center line ensures a sufficiently large second cross-sectional area 8 of the cover 4b to ensure a high inductance of the magnetic core 1. The gap 15 can be ensured, for example, by a spacer (not shown) made of a non-magnetic material. For example, the bottom 4a and the middle region 3 can also be inserted into a plug-in element in order to preferably ensure a plug-in connection between the bottom 4a and the middle region 3, wherein the plug-in element can, for example, form the spacer.

[0042] Figure 5 An electronic device 10 is shown having a magnetic core 1 according to a third exemplary embodiment of the present invention. The third exemplary embodiment corresponds essentially to Figures 1 to 3 The first embodiment is different in that two intermediate regions 3a, 3b are provided, each with a through opening 2a, 2b. Figure 5 In the third embodiment, a gap exists between the intermediate wall 3 c and the bottom 4 a , wherein two outer walls 32 , 31 are arranged seamlessly at the bottom 4 a in order to achieve a particularly advantageous distribution of the magnetic flux density and the magnetic field strength in the magnetic core 1 .

[0043] The two intermediate regions 3a, 3b are respectively arranged between the base 4a and the cover 3, and are directly adjacent to each other in a direction perpendicular to the second sectional planes 7a, 7b. A virtual dividing surface 45 is indicated between the two intermediate regions 3a, 3b. Specifically, when viewed from the inside, the second wall 32 of the first intermediate region 3a and the first wall 31 of the second intermediate region 3b are integrally formed as an intermediate wall 3c. This intermediate wall 3c thus has twice the cross-sectional area of the individual walls 31, 32.

[0044] In the third embodiment, the cross-sectional areas of the two intermediate regions 3a, 3b are considered separately. That is, the cross-sectional area of the magnetic core 1 in the first section plane 6 is twice the first cross-sectional area 8 of each of the intermediate regions 3a, 3b, wherein a second section plane 7a, 7b is defined separately for each intermediate region 3a, 3b.

Claims

1. Magnetic cores for electronic devices, including: - the middle area (3), - a bottom (4a) in the form of a flat plate, and - a cover (4b) in the form of a flat plate, - wherein the intermediate region (3) is arranged between the bottom (4a) and the cover (4b), wherein a through-opening (2) having a center line (X) is formed in the middle region (3), wherein the through-opening (2) divides the middle region (3) into two separate regions, - wherein a first cross-sectional area (9) of the intermediate region (3) in a first sectional plane (6) is substantially equal to a second cross-sectional area (8) of the magnetic core (1) in a second sectional plane (7), wherein the first sectional plane is parallel to the bottom (4a) and the center line (X) lies in the first sectional plane, and the second sectional plane is perpendicular to the first sectional plane (6) and the center line (X) lies in the second sectional plane, and - wherein the bottom (4a) and the cover (4b) protrude beyond the middle region (3) on at least two mutually opposite sides in the direction of the center line (X), wherein the electronic component is at least partially arranged inside a space defined by the cover (4b) and the bottom (4a), The cover (4b) is longer than the bottom (4a) along the direction of the center line (X).

2. The magnetic core according to claim 1, wherein The base (4a) and the cover (4b) protrude over at least 5% of the length (40) of the middle region (3).

3. The magnetic core according to claim 1, wherein The base (4a) and the cover (4b) protrude over at least 10% of the length (40) of the middle region (3).

4. The magnetic core according to claim 1, wherein, The base (4a) and the cover (4b) protrude over a maximum of 50% of the length (40) of the middle region (3).

5. The magnetic core according to any one of claims 1 to 4, wherein, The intermediate region (3) has a first height (35) along a direction (Z) perpendicular to the bottom (4a), the first height being at least 10% of the total height (50) of the magnetic core (1).

6. The magnetic core according to claim 5, wherein, The first height (35) is at least 20% of the total height (50) of the magnetic core (1).

7. The magnetic core according to claim 5, wherein, The first height (35) is a maximum of 40% of the total height (50) of the magnetic core (1).

8. The magnetic core according to any one of claims 1 to 4, wherein, The bottom (4a) and the cover (4b) protrude beyond the middle area (3) on both sides in the direction of the center line (X).

9. The magnetic core according to claim 8, wherein, The bottom (4a) and the cover (4b) protrude symmetrically beyond the middle area (3) on both sides along the direction of the center line (X).

10. The magnetic core according to any one of claims 1 to 4, wherein, The through opening (2) extends from the bottom (4a) to the cover (4b).

11. The magnetic core according to any one of claims 1 to 4, wherein, The base (4a) and the cover (4b) are each designed in the form of a square plate, wherein the base (4a) and the cover (4b) are arranged relative to each other.

12. The magnetic core according to claim 11, wherein, The base (4a) and the cover (4b) are arranged parallel to each other.

13. The magnetic core according to any one of claims 1 to 4, wherein, The magnetic core (1) is constructed in two parts.

14. The magnetic core according to claim 13, wherein, A gap (15) is formed between the middle area (3) and the bottom (4a).

15. The magnetic core according to any one of claims 1 to 4, wherein, The middle region (3), the bottom (4a) and the cover (4b) are formed integrally.

16. The magnetic core according to any one of claims 1 to 4, comprising two intermediate regions (3a, 3b) each having a through opening (2a, 2b), wherein, The two intermediate regions (3a, 3b) are directly adjacent to each other along a direction perpendicular to the second cutting planes (7a, 7b).

17. An electronic device, comprising: - a magnetic core (1) according to any one of claims 1 to 16, and - a printed circuit board (20) that passes through the through-opening (2) and is arranged parallel to the bottom (4a) of the magnetic core (1).

18. The electronic device according to claim 17, further comprising at least one electronic component (60) that is arranged on the printed circuit board (20) and is at least partially covered by the bottom (4a) and the cover (4b) of the magnetic core (1).

Images