JPH09115733A - Coil component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coil component which has a small leakage magnetic flux, small irregularity of an inductance value and a small DC current value, when the DC current is made to flow and an impedance value is decreased by 10%, i.e., a small allowable DC current, and enables manufacturing by a simple assembling work. SOLUTION: This coil component consists of a drum type ferrite magnetic core 1 wherein coil 5 is wound around a core and a tapered part 7 is formed in the peripheral part of the upper surface, and a ring ferrite magnetic core 2 having a protrusion 9 in the upper end portion of the inner wall. The drum type ferrite magnetic core 1 is vertically reversed and inserted into the ring ferrite magnetic core 2. The tapered surface 7 is made to abut against a tapered surface 8 of the magnetic core 2. The central axis of the magnetic core 1 automatically coincides with the central axis of the ring magnetic core 2. The interval between both magnetic cores 1 and 2 is made uniform, which are fixed on a base 4 having lead terminals 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to coil components such as transformers and inductors.

[0002]

2. Description of the Related Art In order to miniaturize electronic equipment, it is required to miniaturize a board on which electronic components are mounted and to realize high-density mounting. When electronic components are mounted on the substrate at a high density, the coil component exerts an influence of the magnetic flux on other electronic components. Therefore, the coil component is structured so that the magnetic flux does not leak, for example, lead terminals as shown in FIG. On the pedestal b in which a is planted, the lower flange of the drum type ferrite magnetic core c on which the winding is wound is fixed by adhesion, and the winding end is entwined with the root of the lead terminal a and soldered, Drum type ferrite magnetic core c
A coil component having a structure in which a ring type ferrite magnetic core d or a pot type ferrite magnetic core e is covered and fixed to a pedestal b is used.

[0003]

In the above-mentioned conventional coil component, the drum-type ferrite magnetic core c and the ring-type ferrite magnetic core d or the pot-type ferrite magnetic core e are outside the flange of the drum-type magnetic core c during molding. It is difficult to make the diameter the same as the inner diameter of the ring-type ferrite magnetic core d or the inner diameter of the pot-type ferrite magnetic core e. Therefore, the drum type ferrite magnetic core c and the ring type ferrite magnetic core d or the pot type ferrite magnetic core e are arranged so that the central axes of the respective magnetic cores coincide with each other in order to obtain the most preferable characteristics as a coil component.
However, in the case of the ring-shaped magnetic core d, it is possible to make the center axis coaxial by visual confirmation,
The work is troublesome, and in the case of the pot type magnetic core e, the inductance value is likely to vary because it cannot be visually confirmed. Therefore, it is troublesome to inspect and select all of them in order to obtain the same inductance value. there were.

The present invention solves the above-mentioned problems of the prior art, and the central axes of both magnetic cores are automatically aligned simply by assembling a magnetic core wound with a winding and a ring type magnetic core or a pot type magnetic core. It is possible to provide a coil component in which the inductance value and the direct current are made to flow with a small amount of magnetic flux leakage and a simple operation, and the dispersion of the direct current value when the impedance value is reduced by 10%, that is, the allowable current value is small. It is intended.

[0005]

In order to achieve the above object, the present invention provides a coil component including a drum type magnetic core and a ring type magnetic core surrounding the drum type magnetic core, as set forth in claim 1. A taper surface is formed on the entire circumference of the peripheral edge of the upper flange of the drum-shaped magnetic core or at least at three or more points distributed over the entire circumference, and on the entire circumference of the upper end of the inner wall of the ring-shaped magnetic core or on the entire circumference. A protrusion having a tapered lower surface or upper surface is formed at least at three or more points dispersed over the entire surface, and the tapered surface of the protrusion of the ring-shaped magnetic core and the tapered surface of the upper flange of the drum-shaped magnetic core are in contact with each other. It is characterized by having done. The drum type magnetic core is
As described in claim 2, the peripheral portion of the upper flange may be covered with the resin molding, and the tapered surface may be formed on the peripheral portion. Further, according to the present invention, as described in claim 3, in a coil component including a drum type magnetic core and a ring type magnetic core surrounding the drum type magnetic core, the drum type magnetic core has at least two locations on a peripheral end surface of an upper flange thereof. To
A notch having a substantially V shape and gradually increasing in depth from above or below to below or above is formed, and the ring-shaped magnetic core has an inverted V of the same shape as the notch at least at two positions on the upper end of the inner wall thereof. A protrusion having a letter-like shape, the height of which gradually increases from the upper side or the lower side to the lower side or the upper side is formed, and the notch of the drum-shaped magnetic core and the protrusion of the ring-shaped magnetic core are brought into contact with their respective tapered surfaces. In a coil component including a drum-shaped magnetic core and a ring-shaped magnetic core surrounding the drum-shaped magnetic core, the drum-shaped magnetic core has an upper flange and a lower flange. The ring-shaped magnetic core is formed to be larger and the peripheral portion of the lower surface thereof is tapered, and the upper end of the inner wall of the ring-shaped magnetic core is formed to be a tapered surface inclined outward, and Characterized in that is brought into contact with tapered surface and the tapered surface of the ring-type magnetic core of the flange, also,
As described in claim 5, in a coil component including a drum type magnetic core and a pot type magnetic core surrounding the drum type magnetic core,
A cone-shaped convex portion is formed on one of the center of the upper surface of the upper flange of the drum-shaped magnetic core and the center of the inner bottom surface of the pot-shaped magnetic core, and a cone-shaped concave portion is formed on the other side, and the cone-shaped convex portion is formed in the cone-shaped concave portion. And a magnetic core having a flange at the other end of the winding core having one end formed in a cone shape, and a cone shape formed in the center of the bottom portion. A coil component comprising a pot-shaped magnetic core having a hole formed therein, wherein the pot-shaped magnetic core has a cone-shaped hole fitted to a cone-shaped end of a winding core of the magnetic core. And surrounding the magnetic core.

According to the first to sixth aspects of the invention, the center axis of the drum-shaped magnetic core is ringed by simply fitting the drum-shaped magnetic core or the magnetic core around which the winding is wound into the ring-shaped magnetic core. The center axis of the die-shaped magnetic core can be automatically matched, and the gap between the flange of the drum-shaped magnetic core and the ring-shaped magnetic core becomes uniform, resulting in 10% of the inductance and impedance values of many coil components. The variation in the direct current value at the time of decrease, that is, the allowable current value is reduced. A drum-shaped magnetic core, wherein a tapered surface is formed on the entire periphery of the peripheral edge of the upper flange, and a projection having a tapered lower surface is formed on the entire periphery of the upper end of the inner wall of the ring-shaped magnetic core. According to the invention described in (4), since the drum type magnetic core around which the winding is wound and the ring type magnetic core are in contact with each other at the tapered portion over the entire circumference, there is almost no leakage magnetic flux,
Further, according to the invention described in claims 5 and 6, since the drum type magnetic core around which the winding is wound and the pot type magnetic core surrounding the drum type magnetic core are provided, there is also no leakage magnetic flux. According to the invention described in claim 6, since the one flange of the drum type magnetic core is not provided, the height of the coil component is reduced.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

Reference numeral 1 denotes a drum type ferrite magnetic core (hereinafter referred to as "drum type magnetic core"), and 2 denotes a ring type ferrite magnetic core (hereinafter referred to as "ring type magnetic core").
Then, these are mounted and mounted on the resin base 4 on which the lead terminals 3 are implanted. Drum magnetic core 1, the winding 5 is wound around the winding core, the tapered surface 7 is formed over the entire circumference in the peripheral portion of the upper surface of the upper flange _61, the ring-type magnetic core 2, the inner diameter Slightly larger than the outer diameter of the upper flange 6 ₁ and the lower flange 6 ₂ of the drum-shaped magnetic core 1 (even if formed to have substantially the same diameter before firing, a gap is formed between both magnetic cores during firing during firing. .), And a projection 9 having a lower surface formed into a tapered surface 8 is provided on the upper end portion of the inner wall of the inner wall.

Drum type magnetic core 1 and ring type magnetic core 2
For assembly, the ring-shaped magnetic core 2 is arranged with the projection 9 facing downward, and the drum-shaped magnetic core 1 is inserted into the ring-shaped magnetic core 2 with the upper flange 6 ₁ facing downward. The taper surface 7 of the upper flange 6 ₁ of the drum-shaped magnetic core 1 contacts the taper surface 8 of the protrusion 9 of the ring-shaped magnetic core 2, and its central axis automatically coincides with the central axis of the ring-shaped magnetic core 2. Placed in position. The upper surface of the upper flange 6 ₁ of the drum-shaped magnetic core 1 and the ring-shaped magnetic core 2 in the arranged state.
Is configured to be substantially flush with the upper end surface of the. Drum type magnetic core 1 and ring type magnetic core 2 assembled
The base 4 is placed on the magnetic core 1, 2
, And the end of the winding wire 5 is entangled with the root of the lead terminal 3 and soldered. According to this configuration, since the drum-type magnetic core 1 and the ring-type magnetic core 2 are in contact with each other by the tapered surfaces 7 and 8, there is almost no leakage magnetic flux between them and the upper surfaces are substantially flush with each other. A short coil component is obtained. For example, in order to obtain an inductance value of 100 μH, a large number of coil parts are formed by winding a winding 5 in which a coated copper wire having a wire diameter of 0.2 mmφ is wound 40 turns around a drum-shaped magnetic core 1 having a flange diameter of 8 mmφ. As a result of making 20 randomly selected samples and measuring the inductance value, the average value was 100 μH, and the variation in the inductance value was 14%. Further, the variation of the DC current value (referred to as an allowable current value) when the inductance value was reduced by 10% from the initial value when no DC current was applied was 24%.

On the other hand, a coated copper wire having a wire diameter of 0.2 mmφ was wound by appropriately adjusting the number of windings so that the inductance value was close to 100 μH, and the taper surface 7 and the projection 9 were formed. In the conventional example under the same conditions as the present invention except that the average value of the inductance values is 10
0 μH, the variation was 28%, and the allowable current value variation was 36%.

As described above, this coil component has smaller variations in the inductance value and the allowable current value than the conventional example.

The allowable current value is such that the direct current is changed by superimposing an alternating current having a frequency of 1 KHz on the direct current flowing through the winding by applying a voltage of 1 V, and the inductance value measured by the LCR meter is 10%. The current value when it decreased was measured.

FIG. 2 shows a second coil component embodying the present invention.

The drum-shaped magnetic core 1a has an upper flange 6
are cutout 10a is formed at three positions on the peripheral end face of a _1, the bottom surface is formed in a tapered surface 7a which is inclined inwardly as they go downward. The ring-shaped magnetic core 2a is formed with three protrusions 9a extending in the central axis direction at a position corresponding to the tapered surface 7a at the upper end portion of the inner wall, and the upper end surface of the ring-shaped magnetic core 2a has the same inclination angle as the tapered surface 7a. A tapered surface 8a is formed so as to incline downward from the top to the top.

To assemble the drum type magnetic core 1a and the ring type magnetic core 2a, the ring type magnetic core 2a is mounted on the base 4, and the drum type magnetic core 1a is inserted into the ring type magnetic core 2a from above. The magnetic core 1a is inserted, and the tapered surface 7a of the magnetic core 1a is brought into contact with the tapered surface 8a of the projection 9a of the ring-shaped magnetic core 2a to be fitted therein, and fixed to the base. In the fitted state, the central axis of the drum-shaped magnetic core 1a automatically coincides with the central axis of the ring-shaped magnetic core 2a. The tapered surface 7a and the projection 9a may be formed in three or more pieces.

In this coil component, the number of turns of the winding 5a is appropriately adjusted so that the inductance value is close to 100 μH, and the shape of the projection 9a having the tapered surface 7a and the tapered surface 8a is illustrated. The coil values are different from those of the coil component shown in FIG. 1, and the others are produced under substantially the same conditions, but as a result of measuring the inductance value by selecting 20 from a large number, the average value is 100 μH, and the variation is 12%. The variation in the allowable current value was 13%.

FIG. 3 shows a third coil component embodying the present invention.

The ring-type magnetic core 2b is substantially the same as the ring-type magnetic core 2 shown in FIG. 1, and the drum-type magnetic core 1b has a taper surface on the entire peripheral surface of the upper flange 6b ₁ thereof. What is covered with the resin molding 11 on which 7b is formed is used.

[0020] The coil component, when upper flange 6b ₁ of the drum-type magnetic core 1b Miniaturization is thin is used to prevent damage to the periphery thereof. The resin molded body 11 absorbs variations in dimensional accuracy of the fired drum-shaped magnetic core 1b and can be easily and accurately combined with the ring-shaped magnetic core 2b. Further, since the distance between the ring-shaped magnetic core 2b and the drum-shaped magnetic core 1b can be adjusted by adjusting the thickness of the resin molded body 11, the ring-shaped magnetic core 2b and the drum-shaped magnetic core 1b having the same size can be adjusted. Resin molded bodies 11 having different thicknesses
By using, it is possible to obtain different inductance values and reduce the manufacturing cost.

In this coil component, the flange of the drum type magnetic core is made small and the resin molded body 11 is provided, and the number of windings of the winding 5 is appropriately adjusted so that the inductance value is close to 100 μH. What is done is only different from the coil component shown in FIG. 1, and the others are made under the same conditions, and a large number of them are produced.
As a result of selecting individual pieces and measuring the inductance values, the average value of the inductance values was 100 μH, and the variation was 10%. Also, the variation in allowable current is 10%
Met.

FIG. 4 shows a fourth coil component embodying the present invention.

The drum-shaped magnetic core 1c has an upper flange 6
A notch 10c having a substantially V shape and having a depth that decreases downward is formed at two opposing positions on the circumferential surface of c _1. The ring-shaped magnetic core 2c has the notch 1 at the upper end of the inner wall thereof.
A projection 9c having an inverted V-shaped cross section having the same shape as that of the cutout 10c at two positions corresponding to 0c, that is, the height gradually decreases downward and both side walls form tapered surfaces 8c, 8c. Triangular projections 9c are formed.
This coil component is also assembled in the same manner as shown in FIG. The notch 10c may be deeply formed downward, and the protrusion 9c may be formed so that the height gradually increases downward, or two or more grooves and protrusions may be formed.

In this coil component, the number of windings of the winding 5c is appropriately adjusted so that the inductance value shows a value close to 100 μH, and the notch 10c of the drum type magnetic core 1c and the protrusion of the ring type magnetic core 2c. Figure 9c
Different from the coil parts shown in Fig. 4, except that the others were made under similar conditions, many were made, 20 of them were selected, and the inductance value was measured. As a result, the average value of the inductance was 100 µH. , The variation is 1
It was 0%. The variation in allowable current was 12%.

FIG. 5 shows a fifth coil component embodying the present invention.

The drum type magnetic core 1d has an upper flange 6
d ₁ is tapered surfaces 7d are formed and the peripheral portion of the lower surface of a large diameter than the lower flange 6d _2, ring magnetic core 2
The upper end edge of the inner wall of d has a tapered surface 8d.

The drum-shaped magnetic core 1d is inserted into the ring-shaped magnetic core 2d fixed to the base 4, and the taper surface 7d of the upper flange 6d ₁ thereof is brought into contact with the taper surface 8d of the ring-shaped magnetic core 2d. It is placed in the ring-shaped magnetic core 2d and fixed to the base 4.

In this coil component, the winding number of the winding 5d is appropriately adjusted so that the inductance value is close to 100 μH, and the taper surface 7d of the drum type magnetic core 1d and the taper surface of the ring type magnetic core 2d are adjusted. Only the shape of 8d is different from the coil component shown in FIG. 1, and the others are made under the same conditions, and a large number of them are prepared. 20 of them are selected and the inductance value is measured. The average value of was 100 μH, and the variation was 14%. The variation in allowable current was 22%.

FIG. 6A shows a sixth coil component embodying the present invention.

This coil component comprises a drum type magnetic core 1e having a winding 5e wound around a winding core and a pot type ferrite magnetic core 12e (hereinafter referred to as a pot type magnetic core). The drum-shaped magnetic core 1e has an upper flange 6e.
_A frustoconical recess 13 is formed in the center of the upper surface of ₁ , and a frustoconical projection 14 having the same shape as the recess 13 is formed in the center of the bottom surface of the pot-type magnetic core 12 fitted therein. .

The drum type magnetic core 1e is arranged and fixed on the base 4, the drum type magnetic core 1e is covered with the pot type magnetic core 12e, and the convex portion 14 is fitted into the concave portion 13 to form the base 4 Fixed to. As shown in FIG. 6B, the recess 13 may be formed in the pot type magnetic core 12f, and the protrusion 14 may be formed in the upper flange 6f ₁ of the drum type magnetic core 1f.

As this coil component, a drum type magnetic core having a concave portion or a convex portion on the upper flange is used, and the wire diameter is 0.
A coated copper wire of 2 mmφ was wound with a winding wire whose number of windings was adjusted so that the inductance value was close to 100 μH, and many pot type magnetic cores 12e and 12f were put on the wound copper wire. As a result of selecting 20 from the above and measuring the inductance value, the average value of the inductance values is 1
It was 00 μH, and the variation was 8%. The variation in allowable current was 13%.

As a result of measuring the same conventional example as shown in FIG. 6 except that the concave portion 13 and the convex portion 14 are not provided, the average inductance value is 100 μH.
The variation was 24%, and the variation in allowable current was 33%. FIG. 7 shows a seventh embodiment of the present invention.
The coil parts of are shown.

In this coil component, a magnetic core 15 having a flange 6g at the lower end of the winding core and a pyramid shape at the upper end,
The bottom plate has a pot-shaped magnetic core 12g having a conical hole 16 formed in the center thereof, and a winding 5g is wound around the core of the magnetic core 15.

To assemble the magnetic core 15 and the pot type magnetic core 12g, the magnetic core 15 is fixed to the base 4, and the pot type magnetic core 12g is provided with the pyramidal holes 16 of the magnetic core 15. The upper end of the shape is fitted and the magnetic core 15 is covered and fixed.

Unlike the drum type magnetic core, the magnetic core 15 of this coil component does not have flanges on both sides. Therefore, if the dimensions are the same, it is necessary to wind a winding having an extra number of turns because one flange is not provided. Therefore, a large inductance value can be obtained. Using a magnetic core having a cone-shaped one end and a flange diameter of 8 mmφ and a pot-type magnetic core having a cone-shaped hole, a coated copper wire having a wire diameter of 0.2 mmφ is used as the inductance value. Is 100μ
A large number of coil components that are the same as those shown in FIG. 6 except that the windings whose winding numbers are adjusted appropriately so as to be close to H are wound are prepared, and 20 coil components are selected from the coil components and their inductance values are set. As a result of the measurement, the average value of the inductance value was 100 μH, and the variation was 12%.
In addition, the variation in allowable current was 21%.

[0037]

According to the present invention, according to the above construction, the leakage magnetic flux is small, and the variation of the direct current value, that is, the allowable current value when the inductance value and the direct current flow and the impedance value is reduced by 10% is small. It has an effect that it can be manufactured by a simple assembling work.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first coil component embodying the present invention.

2A and 2B are an exploded perspective view of a magnetic core of a second coil component embodying the present invention and a cutaway front view of the coil component.

FIG. 3 is a partial cutaway front view of a third coil component according to the present invention.

4A and 4B are an exploded perspective view of a magnetic core of a fourth coil component and a cut-away front view of the coil component.

FIG. 5 is a cutaway front view of a fifth coil component of the present invention.

6A and 6B are cut-away front views of a sixth coil component of the present invention and a modification thereof.

FIG. 7 is a cutaway front view of a seventh coil component of the present invention.

8A and 8B are perspective views of a coil component of a conventional example, respectively.

[Explanation of symbols]

1,1a~1f drum magnetic core 2,2a~2d ring magnetic core 4 base plate 5,5a~5g coil 6 _1, 6a ₁ ~6f ₁ upper flange 7, 7a, 7b, 7d tapered surface 8,8a~ 8d Tapered surface 9, 9a-9c Protrusions 10a, 10c Notch 11 Resin molding 12e, 12f, 12g Pot type magnetic core 13 Recess 14 Convex 15 Magnetic core having a flange at one end

Claims (6)

[Claims] 1. A coil component comprising a drum-shaped magnetic core and a ring-shaped magnetic core surrounding the drum-shaped magnetic core, wherein at least three locations are distributed over the entire circumference of the peripheral portion of the upper flange of the drum-shaped magnetic core or over the entire circumference. The tapered surface is formed as described above, and the projections having the lower side surface or the upper side surface as the tapered surface are formed at least at three or more locations distributed over the entire circumference of the upper end portion of the inner wall of the ring-shaped magnetic core. A coil component, wherein the tapered surface of the protrusion of the ring-shaped magnetic core and the tapered surface of the upper flange of the drum-shaped magnetic core are brought into contact with each other. 2. The drum type magnetic core according to claim 1, wherein a peripheral edge portion of an upper flange of the drum type magnetic core is covered with a resin molding, and a taper surface is formed on the peripheral edge portion. Coil parts. 3. A coil component comprising a drum-shaped magnetic core and a ring-shaped magnetic core surrounding the drum-shaped magnetic core, wherein the drum-shaped magnetic core is substantially V-shaped and upward or at least at two positions on the peripheral end surface of the upper flange. A notch is formed which gradually becomes deeper from the lower side to the lower side or the upper side, and the ring-shaped magnetic core has an inverted V-shaped cross-section having the same shape as the notch at at least two positions on the upper end portion of the inner wall thereof. A protrusion that gradually increases from the upper side or the lower side to the lower side or the upper side is formed, and the notch of the drum-shaped magnetic core and the protrusion of the ring-shaped magnetic core are fitted with their tapered surfaces in contact with each other. Coil parts to do. 4. A coil component comprising a drum-shaped magnetic core and a ring-shaped magnetic core surrounding the drum-shaped magnetic core, wherein the drum-shaped magnetic core has an upper flange larger than the lower flange and a peripheral surface of a lower surface formed into a tapered surface. The ring-shaped magnetic core is characterized in that the upper end of its inner wall is formed into a tapered surface that is inclined outward, and the tapered surface of the upper flange of the drum-shaped magnetic core and the tapered surface of the ring-shaped magnetic core are in contact with each other. And coil parts. 5. A coil component comprising a drum-shaped magnetic core and a pot-shaped magnetic core surrounding the drum-shaped magnetic core, wherein a cone-shaped projection is formed on one of the center of the upper surface of the upper flange of the drum-shaped magnetic core and the center of the inner bottom surface of the pot-shaped magnetic core. A coil component, characterized in that a conical concave portion is formed on the other side, and the conical convex portion is fitted into the conical concave portion. 6. A coil component comprising a magnetic core having a flange at the other end of a winding core having one end formed in a cone shape, and a pot-type magnetic core having a cone-shaped hole formed at the center of the bottom. The pot type magnetic core surrounds the magnetic core by fitting a conical hole into one end of the magnetic core, which is formed in a conical shape of a winding core.