JP7506982B2 - Inductors - Google Patents

Description

The present invention relates to an inductor.

In inductors, windings may be provided in multiple sections separated by partitions for various purposes. For example, in common mode choke coils, partitions may be used to insulate multiple windings from each other. Also, for example, in normal mode choke coils, partitions may be used to control frequency characteristics. Patent Document 1 discloses a core case structure with partitions that can be used for such inductors.

Patent No. 6555754

The objective of the present invention is to provide an inductor that is inexpensive and has superior characteristics compared to inductors that use a case.

The present invention provides a first inductor,
An inductor comprising a fixed member, a magnetic core, and a coil,
The fixing member has a central axis extending in a vertical direction, n partition plate portions, and m bottom plate portions,
n is an integer of 2 or more,
m is an integer between n/2 and n,
Each of the partition plate portions extends from the central axis in a direction perpendicular to the up-down direction,
Each of the partition plate portions is connected to the other partition plate portion by any one of the bottom plate portions,
The magnetic core is coated with an insulating material and has an annular shape with a hole therein,
the magnetic core is mounted on the bottom plate portion such that the partition plate portion is disposed in the hole portion,
The coil provides an inductor that is wound directly on the magnetic core, excluding the bottom plate portion.

In addition, the present invention provides a first inductor as the second inductor,
The magnetic core provides an inductor having a toroidal shape.

Furthermore, the present invention provides a third inductor which is a first or second inductor,
m is equal to n,
The bottom plate portions are connected to each other in a horizontal plane perpendicular to the up-down direction to provide an inductor that forms a closed ring-shaped core base.

Furthermore, the present invention provides a fourth inductor, which is any one of the first to third inductors,
The magnetic core has an inner circumferential surface and an outer circumferential surface,
Each of the bottom plate portions provides an inductor that is located only in a region sandwiched between the inner peripheral surface and the outer peripheral surface in a horizontal plane perpendicular to the up-down direction.

Furthermore, the present invention provides a fifth inductor, which is any one of the first to fourth inductors,
the fixing member further includes a base portion to be mounted on a circuit board when the inductor is used;
At least two terminal holes are formed in the base portion,
An inductor is provided in which the ends of the coil are inserted into the terminal holes.

Furthermore, the present invention provides a sixth inductor, which is the fifth inductor,
Each of n and m is 3;
The partition plate portion includes first to third partition plate portions,
The hole portion is divided into a first section, a second section, and a third section by the first to third partition plate portions,
The first section faces the first partition plate portion and the second partition plate portion,
The second section faces the second partition plate portion and the third partition plate portion,
The third section faces the third partition plate portion and the first partition plate portion,
The second partition plate portion is lower than the first partition plate portion and the third partition plate portion,
the base portion is provided corresponding to the first to third partition plate portions,
The terminal hole includes a first terminal hole and a second terminal hole,
the first terminal hole is provided in the base portion corresponding to the first partition plate portion,
the second terminal hole is provided in the base portion corresponding to the second partition plate portion,
The coil has a first end and a second end as the end portion,
The first end of the coil is inserted into a first terminal hole,
The coil is wound in the order of the first section, the second section, and the third section,
The second end of the coil provides an inductor that is inserted into the second terminal hole after the coil is wound around the third section and passes over the central axis and the second partition plate portion.

The fixing member of the present invention has a bottom plate portion and a partition plate portion connected thereto. Therefore, when a magnetic core is mounted on the bottom plate portion and a wire is wound around the magnetic core to form a coil, the positional relationship between the partition plate portion and the magnetic core is fixed, and variation in the size of the compartments divided by the partition plate portion can be suppressed.

The coil of the present invention is wound directly on the insulating coated magnetic core, except for the bottom plate portion. Therefore, compared to when a case is used, a larger area can be reserved for the coil, and the number of turns can be increased. On the other hand, if the number of turns is kept constant, the total length of the wire can be shortened compared to when a case is used, which reduces material costs and reduces DC resistance to suppress heat generation.

1 is a perspective view showing an inductor according to an embodiment of the present invention; 2 is a perspective view showing a fixing member included in the inductor of FIG 1. The perspective direction is different from that of the fixing member of FIG 1. FIG. 3 is a top view showing the fixing member of FIG. 2 . 2 is a perspective view showing a magnetic core included in the inductor of FIG. 1 . 4 is a top view showing an intermediate body in which a magnetic core is mounted on the fixing member of FIG. 3 . FIG. 13 is a top view showing a fixing member according to a modified example. FIG. 13 is a top view showing a fixing member according to another modified example. FIG. 13 is a top view showing a fixing member according to still another modified example.

Referring to FIG. 1, an inductor 1 according to an embodiment of the present invention includes a fixed member 10, a magnetic core 30, and a coil 50. The inductor 1 of this embodiment is a normal mode choke coil. However, the present invention is not limited to this. The inductor may be a common mode choke coil or other inductors.

2 and 3, the fixing member 10 has a central axis 12 extending in the vertical direction, n partition plate portions 14a, 14b, 14c, and m bottom plate portions 18a, 18b, 18c. Here, n is an integer of 2 or more, and m is an integer of n/2 or more and n or less. In this embodiment, m is equal to n. Specifically, in this embodiment, m and n are each 3. That is, the fixing member 10 according to this embodiment has three partition plate portions, the first partition plate portion 14a, the second partition plate portion 14b, and the third partition plate portion 14c, and three bottom plate portions 18a, 18b, 18c.

As shown in FIG. 3, each of the partition plate portions 14a, 14b, and 14c extends from the central axis 12 in a direction perpendicular to the up-down direction. That is, the partition plate portions 14a, 14b, and 14c extend radially from the central axis 12. As shown in FIG. 2, in this embodiment, the second partition plate portion 14b is lower than the first partition plate portion 14a and the third partition plate portion 14c.

2 and 3, each of the partition plate portions 14a, 14b, and 14c is connected to the other partition plate portions 14a, 14b, and 14c by one of the bottom plate portions 18a, 18b, and 18c. Specifically, the first partition plate portion 14a is connected to the second partition plate portion 14b by the bottom plate portion 18a, the second partition plate portion 14b is connected to the third partition plate portion 14c by the bottom plate portion 18b, and the third partition plate portion 14c is connected to the first partition plate portion 14a by the bottom plate portion 18c. In this way, the partition plate portions 14a, 14b, and 14c and the bottom plate portions 18a, 18b, and 18c are fixed to each other.

As described above, in this embodiment, the number n of partition plate portions 14a, 14b, and 14c is equal to the number m of bottom plate portions 18a, 18b, and 18c. Therefore, as shown in FIG. 3, bottom plate portions 18a, 18b, and 18c are connected to each other in a horizontal plane perpendicular to the up-down direction to form a closed ring-shaped core base 16.

Referring to Figs. 1 to 3, the fixing member 10 of this embodiment further includes base portions 20a, 20b, and 20c that are mounted on a circuit board when the inductor 1 is in use. The base portions 20a, 20b, and 20c are intended to stabilize the position of the inductor 1 on the circuit board. The base portions 20a, 20b, and 20c are also intended to align the ends of the coil 50 to ensure their position, as described below. For this purpose, a first terminal hole 22a is formed in the base portion 20a, and a second terminal hole 22b is formed in the base portion 20b. That is, in this embodiment, two terminal holes are formed in the base portion. However, the present invention is not limited to this, and it is sufficient that at least two terminal holes are formed in the base portion.

As shown in FIG. 3, the base portions 20a, 20b, and 20c are provided corresponding to the first to third partition plate portions 14a, 14b, and 14c. The first terminal hole 22a is provided in the base portion 20a corresponding to the first partition plate portion 14a. The second terminal hole 22b is provided in the base portion 20b corresponding to the second partition plate portion 14b.

Referring to FIG. 4, the magnetic core 30 is coated with insulation and has an annular shape with a hole 32 inside. In particular, the magnetic core 30 of this embodiment has a circular ring shape. The magnetic core 30 has a top surface 34, a bottom surface 36, an inner peripheral surface 38, and an outer peripheral surface 40.

As can be seen from Figures 2, 4, and 5, the magnetic core 30 is mounted on the bottom plate portions 18a, 18b, and 18c, with the partition plate portions 14a, 14b, and 14c positioned in the hole portion 32. As shown in Figure 5, in this embodiment, the bottom plate portions 18a, 18b, and 18c are each located only in the area between the inner peripheral surface 38 and the outer peripheral surface 40 in a horizontal plane perpendicular to the up-down direction.

5, the hole 32 is divided into three sections, a first section 32a, a second section 32b, and a third section 32c, by the first to third partition plate sections 14a, 14b, and 14c. The first section 32a faces the first partition plate section 14a and the second partition plate section 14b. In other words, the first section 32a is an area surrounded by the first partition plate section 14a, the second partition plate section 14b, and the inner peripheral surface 38. The second section 32b faces the second partition plate section 14b and the third partition plate section 14c. In other words, the second section 32b is an area surrounded by the second partition plate section 14b, the third partition plate section 14c, and the inner peripheral surface 38. The third section 32c faces the third partition plate portion 14c and the first partition plate portion 14a. In other words, the third section 32c is an area surrounded by the third partition plate portion 14c, the first partition plate portion 14a, and the inner peripheral surface 38.

1 to 5, the coil 50 is wound directly on the magnetic core 30, except for the bottom plate portions 18a, 18b, and 18c, with the insulating coated magnetic core 30 mounted on the core base 16 (i.e., the bottom plate portions 18a, 18b, and 18c). In other words, the coil 50 is wound on the magnetic core 30 together with the bottom plate portions 18a, 18b, and 18c. By winding the coil 50 on the magnetic core 30 mounted on the bottom plate portions 18a, 18b, and 18c, the bottom plate portions 18a, 18b, and 18c and the magnetic core 30 are integrated, and the positional relationship between the partition plate portions 14a, 14b, and 14c and the magnetic core 30 is fixed. Therefore, the partition plate portions 14a, 14b, and 14c can be prevented from moving relative to the magnetic core 30 during winding, and as a result, the variation in size of the first section 32a, the second section 32b, and the third section 32c divided by the partition plate portions 14a, 14b, and 14c can be suppressed. In other words, since the partition plate portions 14a, 14b, and 14c and the bottom plate portions 18a, 18b, and 18c are fixed to each other, deformation of the fixed members due to stress when winding the coil 50 can be prevented, and the variation in size of the first section 32a, the second section 32b, and the third section 32c divided by the partition plate portions 14a, 14b, and 14c can be suppressed.

The coil 50 is wound directly on the magnetic core 30, which is coated with insulation, except for the bottom plate portions 18a, 18b, and 18c. Therefore, compared to when a case is used, a larger area can be reserved for the coil 50, and the number of turns can be increased. On the other hand, if the number of turns is constant, the total length of the wire required to form the coil 50 can be shortened compared to when a case is used. Therefore, material costs can be reduced, and the DC resistance can be reduced to suppress heat generation. In particular, as described above, each of the bottom plate portions 18a, 18b, and 18c according to this embodiment is located only in the area between the inner peripheral surface 38 and the outer peripheral surface 40 in a horizontal plane perpendicular to the up-down direction. Therefore, it is possible to avoid the length of the winding of the coil 50 becoming unnecessarily long.

As shown in FIG. 1, the coil 50 has a first end 52 and a second end 54 as ends. The first end 52 and the second end 54 of the coil 50 are inserted into the first terminal hole 22a and the second terminal hole 22b of the fixing member 10, respectively. This allows the positional relationship between the first end 52 and the second end 54, i.e., the terminal pitch, to be as designed. In detail, as can be seen from FIG. 1 and FIG. 5, after the first end 52 of the coil 50 is inserted into the first terminal hole 22a, the coil 50 is wound around the first section 32a, the second section 32b, and the third section 32c in that order. Then, as can be seen from FIG. 1 and FIG. 5, the second end 54 of the coil 50 is inserted into the second terminal hole 22b, passing over the central axis 12 and the second partition plate portion 14b, after the coil 50 is wound around the third section 32c.

In the above-mentioned embodiment, the number n of the partition plate portions 14a, 14b, 14c is equal to the number m of the bottom plate portions 18a, 18b, 18c, but the present invention is not limited to this. For example, the fixed member 10d shown in FIG. 6 has three partition plate portions 14d and two bottom plate portions 18d. Each of the partition plate portions 14d is connected to the other partition plate portions 14d by one of the bottom plate portions 18d, and the positional relationship between the partition plate portions 14d and the bottom plate portions 18d is thereby fixed. Therefore, even in the modified example of FIG. 6, if the magnetic core 30 of FIG. 4 is mounted on the bottom plate portion 18d and the coil 50 is wound around the magnetic core 30, the variation in the size of the sections defined by the partition plate portions 14d can be suppressed.

In the above embodiment, the number n of the partition plate portions 14a, 14b, and 14c is 3, but the present invention is not limited to this. n may be 2, or 4 or more. For example, the fixing member 10e shown in FIG. 7 has six partition plate portions 14e and six bottom plate portions 18e. Each of the partition plate portions 14e is connected to the other partition plate portions 14e by any of the bottom plate portions 18e, and the positional relationship between the partition plate portions 14e and the bottom plate portions 18e is fixed. In particular, in the fixing member 10e of FIG. 7, the six bottom plate portions 18e are connected to each other in a horizontal plane perpendicular to the up-down direction to form a closed ring-shaped core base 16e. In the case of this modified example, the same effect as the inductor 1 of FIG. 1 described above can be obtained. In addition, the fixing member 10e of FIG. 7 is provided with a base portion corresponding to each of the partition plate portions 14e. That is, the fixing member 10e has six base parts corresponding to the six partition plate parts 14e. However, the present invention is not limited to this, and the base parts need only be provided to the extent that the position of the inductor can be stabilized on the circuit board and the end position of the coil can be guaranteed.

Furthermore, the modified examples shown in Fig. 6 and Fig. 7 may be combined. For example, the fixed member 10f shown in Fig. 8 has six partition plate portions 14e and three bottom plate portions 18e. In this modified example, each of the partition plate portions 14e is connected to the other partition plate portions 14e by any of the bottom plate portions 18e, and the positional relationship between the partition plate portions 14e and the bottom plate portions 18e is fixed. Therefore, in this modified example, the same effect as the inductor 1 of Fig. 1 described above can be obtained. However, as in the fixed member 10f of Fig. 8, if the number m of the bottom plate portions is too small compared to the number n of the partition plate portions, the fixed member may be deformed when the coil is wound, and there is a risk that the partition portions divided by the partition plate portions may vary. In order to avoid such problems, it is desirable that the fixed member has a bottom plate portion corresponding to all the partitions, or a bottom plate portion corresponding to all the other partitions except one partition. When the fixing member has a bottom plate portion so that it corresponds to all the compartments, the number of bottom plate portions m is equal to the number of partition plate portions n. On the other hand, when the fixing member has a bottom plate portion so that it corresponds to all the compartments except for one compartment, the number of bottom plate portions m is equal to the number of partition plate portions n minus 1. For the above reasons, in order to minimize the variation in the compartments, it is desirable for m to be n-1 or greater.

REFERENCE SIGNS LIST 1 inductor 10, 10d, 10e, 10f fixed member 12 central axis 14a, 14b, 14c, 14d, 14e partition plate portion 16, 16e core base 18a, 18b, 18c, 18d, 18e bottom plate portion 20a, 20b, 20c base portion 22a, 22b terminal hole 30 magnetic core 32 hole portion 32a first section 32b second section 32c third section 34 upper surface 36 bottom surface 38 inner peripheral surface 40 outer peripheral surface 50 coil 52 first end 54 second end

Claims (4)

An inductor comprising a fixed member, a magnetic core, and one coil,
The fixing member is an integral member having a central axis extending in a vertical direction, n partition plate portions, and m bottom plate portions,
n is an integer of 2 or more,
m is an integer between n/2 and n,
Each of the partition plate portions extends from the central axis in a direction perpendicular to the up-down direction,
Each of the partition plate portions is connected to either one of the other partition plate portions or the bottom plate portion, thereby fixing a positional relationship between the partition plate portion and the bottom plate portion;
The magnetic core is coated with an insulating material and has an annular shape with a hole therein,
With the partition plate portion disposed in the hole, the magnetic core is mounted on the bottom plate portion, and the coil is wound directly on the magnetic core, except for the bottom plate portion;
The coil is wound around the magnetic core together with the bottom plate portion ,
The coil has a first end and a second end as ends,
the fixing member further includes a base portion to be mounted on a circuit board when the inductor is used;
The base portion has a first terminal hole and a second terminal hole formed therein,
Each of n and m is 3;
The partition plate portion includes first to third partition plate portions,
The hole portion is divided into a first section, a second section, and a third section by the first to third partition plate portions,
The first section faces the first partition plate portion and the second partition plate portion,
The second section faces the second partition plate portion and the third partition plate portion,
The third section faces the third partition plate portion and the first partition plate portion,
The second partition plate portion is lower than the first partition plate portion and the third partition plate portion,
the base portion is provided corresponding to the first to third partition plate portions,
the first terminal hole is provided in the base portion corresponding to the first partition plate portion,
the second terminal hole is provided in the base portion corresponding to the second partition plate portion,
The first end of the coil is inserted into a first terminal hole,
The coil is wound in the order of the first section, the second section, and the third section,
The second end of the coil is wound around the third section, and then passes over the central axis and the second partition plate portion and is inserted into the second terminal hole.
Inductor. 2. The inductor of claim 1,
The magnetic core is an inductor having a circular ring shape. 3. The inductor according to claim 1,
m is equal to n,
The bottom plate portions are connected to each other in a horizontal plane perpendicular to the up-down direction to form a closed ring-shaped core base. An inductor according to any one of claims 1 to 3,
The magnetic core has an inner circumferential surface and an outer circumferential surface,
An inductor in which each of the bottom plate portions is located only within a region sandwiched between the inner peripheral surface and the outer peripheral surface in a horizontal plane perpendicular to the up-down direction.

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