JPH09129458A - Coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil having improved characteristics. SOLUTION: A coil comprises a plurality of turns of conductor in an insulating member 1. The individual turns of conductor are located in different planes and their diameters gradually change from one end to the other. In this structure, the stray capacitance between turns and the resistance of the conductor can be reduced, and this coil is easy to assemble.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil component used in various electronic devices, communication devices and the like.

[0002]

2. Description of the Related Art Coil components are widely used as coils and transformers for various electronic devices and communication devices. In recent years, small or thin coil components have been increasingly required. As a result, coil components as noise suppression components are becoming more and more important.

As a conventional coil component satisfying these demands, a laminated coil component obtained by alternately laminating ferrite magnetic layers and coil conductor layers (for example, Japanese Patent Publication No. 57-3).
9521).

In this laminated coil component, as shown in FIGS. 12 and 13, a ferrite layer 12 is formed by printing on a half of a ferrite green sheet 16, and a portion without the ferrite layer 12 and a portion of the ferrite layer 12 are formed. An L-shaped conductor pattern 13 is formed by printing on the conductor pattern 13, and about half the ferrite layer 14 of the green sheet 16 is printed on the conductor pattern 13, and the ferrite layer 12 and the ferrite layer 12 are continuous so as to be continuous with the conductor pattern 13. A U-shaped conductor pattern 15 is printed on a part of 14 and this process is repeated several times to collectively fire one in which a ferrite green sheet 16 is laminated on the uppermost layer, and end face electrodes 17 are formed on both ends of this laminated body. Formed and configured.

[0005]

With the above-mentioned structure, it is necessary to increase the number of turns of the conductor pattern in order to obtain a large inductance, and an extremely large number of ferrite layers 12 and 14 and conductor patterns 13 and 15 are laminated. Since it is necessary to print, the number of production steps increases, and there is a problem in terms of productivity. Moreover, since the conductor patterns 15 are formed so as to face each other with the ferrite layers 12 and 14 interposed therebetween,
There are problems that the stray capacitance between the conductor patterns is increased, the self-resonance frequency is reduced as a coil component, and the breakdown voltage is low.

Further, in this laminated coil component, since the conductor pattern is formed on a part of the ferrite layer, if the thickness of the conductor pattern is increased in order to reduce the resistance of the coil conductor, the entire thickness of the conductor pattern 13 is reduced. , 15 and the part where there is no marked difference, and cracks were generated even if fired, and a coil component of stable quality could not be obtained.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and to provide a coil component which is excellent in productivity and has a small stray capacitance and excellent electric characteristics.

[0008]

In order to solve the above problems, the coil component of the present invention comprises a conductor having a plurality of turns in an insulator, and the diameter of each turn portion of the conductor gradually increases from one end to the other end. It is configured such that it is different and at least each turn portion is located in a different plane.

According to the present invention, a coil component having excellent productivity and excellent electrical characteristics can be obtained.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention comprises a conductor having a plurality of turns in an insulator, and the diameter of each turn portion of this conductor gradually changes from one end to the other end, and at least Since the turn parts are located in different planes, it is easy to produce, and the stray capacitance between the turn parts of the conductor is small, and the electrical characteristics are excellent.

According to the second aspect of the present invention, each turn portion of the conductor is formed in the same plane from one end to the other end, and is connected to the adjacent turn portion at the terminal end or the starting end of each turn. Therefore, it is possible to easily form the extraction lead.

According to the third aspect of the invention, the conductor is formed into a three-dimensional spiral winding from one end to the other end, and the conductor can be formed very easily.

The invention described in claims 4 and 5 is
The shape of each turn portion of the conductor is circular or rectangular, which facilitates formation of the conductor pattern and can obtain a large inductance in the same volume.

According to a sixth aspect of the present invention, a conductor is formed so that a gap between the conductors cannot be seen between the turn portions when viewed from the side of the large-diameter turn portion. Since a conductor having a large width can be formed in a limited space, excellent characteristics can be obtained.

According to a seventh aspect of the present invention, the conductor has a rectangular cross section, a circular shape, or a semicircular cross section, whereby the conductor cross section can be increased and the DC conductor resistance can be reduced.
It can also be used for high power.

According to the invention of claim 8, a non-magnetic material is used as an insulator, and the self-resonant frequency is increased and the frequency band used is widened.

According to the ninth aspect of the present invention, a magnetic body is used as an insulator, and a large inductance value can be obtained.

According to a tenth aspect of the present invention, the outer and inner insulators of the conductor are made of different magnetic properties,
It is possible to realize coil components having various inductance values or coil components having various DC superposition characteristics with the same conductor structure.

According to the eleventh aspect of the present invention, a non-magnetic material and a magnetic material are used as those having different magnetic properties, and the direct current superposition characteristic or the used frequency band can be improved.

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is a perspective view schematically seeing through a typical example of the coil component of the present invention. That is, the conductor 2 having a plurality of turns is built in the insulator 1, and the conductor 2 is formed by a circle in which the diameter of each turn portion gradually increases from one end to the other end, and the positions of the turn portions are different from each other. It is located in the plane. That is, one end of the conductor 2 is formed of a small diameter circle, and the diameter is gradually increased toward the other end, and each turn portion thereof rises or falls at the end or the start end and is adjacent to the adjacent turn. Connected to the department. Therefore, each turn portion is located on the same plane, and adjacent turn portions are located on different plane portions depending on rising and falling portions, and are set to have different diameters.

Lead-out portions 3 and 4 are provided at both ends of the conductor 2, and the lead-out portions 3 and 4 are connected to end face electrodes 5 and 6 provided on both sides of the insulator 1, respectively.

Each turn in this case is as shown in FIG.
It means a conductor existing in the same plane. That is, in the example shown in FIG. 1, it can be said that each turn is formed on four planes.

The coil component shown in FIG. 2 has a three-dimensional spiral shape in which the conductor 2 has a diameter gradually increasing from one end to the other end and the positions thereof are all located in different planes. Has the same configuration as in FIG.

FIG. 3 is a sectional view of the coil component shown in FIGS. 1 and 2, in which the conductor 2 is formed on a certain inclined surface in the insulator 1. Insulator 1 here
Is made of one kind of material, and the insulator 1 may be a non-magnetic material or a magnetic material.

As the non-magnetic substance, any electrically insulating material such as an organic insulating material such as glass epoxy or polyimide, an inorganic insulating material such as glass, glass ceramics or ceramics can be used. May be.

As the magnetic material, NiZn system or NiZnC is used.
Any ferrite material having a generally high magnetic permeability, such as a u-based material, may be used.

When the insulator 1 is made of a magnetic material, the inductance value can be increased, and when the insulator 1 is made of a non-magnetic material, a large inductance value cannot be obtained. The band becomes wider.

Any material may be used as the material for the conductor 2 or the lead-out portions 3 and 4 as long as it is an electrically good conductor. However, since a material having a low resistivity and a low resistance is required for the coil component, copper and silver are used. Conductive materials such as palladium alloy or silver are effective.

The end face electrodes 5 and 6 may be made of a conductive material. Generally, it is desirable that the end face electrodes 5 and 6 are composed of a plurality of layers instead of a single layer, and in the case of surface mounting, they are mounted on a printed wiring board. It is necessary to consider the mounting strength at the time of soldering, the wettability of solder at the time of mounting, the solder nick, etc. Specifically, use the same conductor material as the lead-out parts 3 and 4 for the lowermost layer, and to the solder for the intermediate layer. And nickel having high resistance to the solder, and solder or tin having good wettability to solder are used for the outermost layer.

However, this is an example, and it is not always necessary to adopt this configuration, and a conductive resin material may be included in addition to a material having excellent conductivity such as metal.

Further, a predetermined wiring pattern is formed on a ceramic substrate such as alumina or ferrite, a window is provided on the ceramic substrate to insert a coil component, and the wiring pattern and the end face electrodes 5, 6 of the coil component are brought into contact with each other to form a thick film. Since it is fired using the formation process and electrically connected, heat resistance can be improved and a structure corresponding to this thick film formation process can be considered.

Next, the coil component shown in FIG. 4 will be described. In the structure shown in FIG. 4, the outer and inner sides of the insulator 1 are different from each other with respect to the conductor 2 and have different magnetic properties. That is, in FIG. 4, the outer insulator 1a is made of a non-magnetic material, the outer insulator 1a is the outer side, and the inner side is the inner insulator 1b.
When b is made of a magnetic material, the coil component has a smaller inductance value than the case where both the outer insulator 1a and the inner insulator 1b are made of a magnetic material, but the direct current superposition characteristic can be significantly improved. it can. That is, even if the current value is changed, the change in the inductance value can be reduced,
The allowable current value can be increased.

On the other hand, if the outer insulator 1a is made of a magnetic material and the inner insulator 1b is made of a non-magnetic material, the DC superposition characteristics can be greatly improved in the same manner as described above, and a coil component with less leakage magnetic flux can be obtained. be able to.

Further, both the outer insulator 1a and the inner insulator 1b are made of magnetic material, and the magnetic flux density is magnetically different, so that the direct current superposition characteristic can be improved. For example, by increasing the magnetic flux density of the magnetic material located in the portion where the diameter of each turn is small, it is possible to enhance the DC superimposition characteristics without changing the three-dimensional arrangement of the conductors. As yet another example, when the outer insulator 1a is designed to have a small thickness, the magnetic flux density of the outer insulator 1a can be increased to similarly enhance the DC superposition characteristic.

Further, the outer insulator 1a and the inner insulator 1b
Are made of a magnetic material and have magnetic properties that are magnetically different from each other, so that coil components having the same conductor structure and different inductance values can be obtained. In this case, there is no particular limitation on the magnitude relationship of the magnetic permeability between the outer insulator 1a and the inner insulator 1b.

By properly selecting the magnetic properties of the outer insulator 1a and the inner insulator 1b as described above, the inductance value as a coil component can be arbitrarily selected and the leakage magnetic flux or the DC superposition characteristic can be controlled. Will be free to do.

Next, the coil components shown in FIGS. 5 to 8 will be described. This coil component basically provides a conductor 2 having a large cross-sectional area to reduce the conductor resistance and can be used for a large current.

First, in the structure shown in FIG. 5, all the cross sections of the conductor 2 are triangular, and the cross sectional area is remarkably increased as compared with a flat film-shaped structure. In order to obtain this structure, the insulator 1 is prepared by dividing it into the outer insulator and the inner insulator as described above, and a step-like step portion is provided in the central portion of the outer insulator, and the step portion is electrically conductive. The conductor 2 having a triangular cross section can be realized by applying a paste and curing it, and then incorporating and sintering an internal insulator.

In the structure shown in FIG. 6, any cross section of the conductor 2 has a rectangular shape to increase the cross-sectional area. To achieve this structure, a step-like stepped portion is formed on the outer insulator and the inner insulator. A conductor 2 having a rectangular cross section can be formed by combining the outer conductor and the inner insulator with the triangular conductor paste provided here, and finally the inner and outer insulators are integrated. It can be realized by applying heat treatment.

In FIG. 7, the conductor 2 has a circular cross section, and in this structure also, a semicircular recess is provided in the inner and outer insulators, and the recess is filled with a conductor paste. As a result, a coil component having the conductor 2 having a circular cross section can be obtained.

FIG. 8 shows a conductor 2 having a semi-circular cross section, which has a semi-circular recess in the outer insulator and is filled with a conductor paste for internal insulation. A coil component having the conductor 2 having a semicircular cross-sectional area can be obtained by combining the bodies and heat-treating them.

Although circular or semi-circular shape is used in FIGS. 7 and 8, it is needless to say that the shape is not limited to a perfect circle and may be an ellipse or an ellipse. Further, in addition to the rectangular cross section shown in FIG. 6, a polygonal cross section such as a pentagon or a hexagon may be used.

Next, the coil component shown in FIG. 9 will be described. This coil component is configured such that no gap is visible between the turn portions of the conductor 2 when viewed from the large diameter side as the conductor 2, and by adopting this configuration, the magnetic flux that turns around only each turn portion of the conductor 2 is reduced. In addition, the proportion of the conductor 2 in the limited area forming the conductor 2 can be increased, the DC resistance can be reduced, and as a result, a coil component having a large inductance value can be obtained.

Further, as shown in FIG. 10, as the conductor 2,
Although FIG. 1 and FIG. 2 show what is constituted by a circular turn portion, a prismatic columnar component is originally preferred as a surface-mount type coil component, and each columnar coil component has a square-shaped turn. It is possible to form a square-shaped turn portion that fills the outer shape of the coil component.

Although the rectangular conductor 2 is also shown in FIG. 10 as a rectangular solid spiral shape, the rectangular turn portions are in the same plane and are adjacent to each other at the end or the start. It is also possible to adopt a configuration in which it is connected to the turn portion.

As a final example, the coil component shown in FIG. 11 will be described. The conductor shown in FIG. 11 has a conductor structure in which both ends have a large diameter and the middle part has a small diameter, and the conductor 2 has a structure in which two conductors described so far are combined.

This is because there is a possibility that stray capacitances will be generated by forming a pair of conductors having the same diameter as the turn portions, but the turn portions having the same diameter are located far apart from each other, so that they occur between them. The stray capacitance generated is almost negligible.

As described in many examples above, the insulator 1
Since the conductor 2 is continuously formed on a certain inclined surface in the inside, unlike the conventional laminated structure, it is easy to produce and the yield can be improved, and the neighboring turn portion is formed by the insulator 1. Since it does not face each other through the, the occurrence of stray capacitance can be suppressed to the minimum, so that it is possible to prevent that the self-resonance frequency becomes small and high attenuation cannot be obtained in a wide band when it is used as a filter. The coil component can be remarkably excellent in performance.

In the above embodiment, only the surface mounting type having the end face electrodes 5 and 6 provided at both ends has been described. However, the insulator 1 having the pin terminals planted therein, and the end face electrodes having the end face electrodes are provided. Alternatively, a lead-type coil component in which cap-shaped electrodes having terminals are fitted and coupled to both ends of an insulator can be used.

[0050]

As is apparent from the above description, the coil component of the present invention has a high productivity because it does not have a laminated structure, and the height is low because the conductor is positioned on the inclined surface inside the insulator. It can be suppressed, and the stray capacitance between the turn parts of the conductor is hardly generated, and the electrical characteristics can be made excellent, which is of great industrial value.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a coil component according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view of another embodiment.

FIG. 3 is a sectional view of the same.

FIG. 4 is a cross-sectional view of another embodiment.

FIG. 5 is a sectional view of still another embodiment.

FIG. 6 is a sectional view of still another embodiment.

FIG. 7 is a sectional view of still another embodiment.

FIG. 8 is a sectional view of still another embodiment.

FIG. 9 is a sectional view of still another embodiment.

FIG. 10 is a schematic perspective view showing still another embodiment.

FIG. 11 is a sectional view of still another embodiment.

FIG. 12 is a schematic perspective view showing a conventional coil component.

FIG. 13 is an exploded perspective view of the same.

[Explanation of symbols]

 1 Insulator 1a Outer Insulator 1b Inner Insulator 2 Conductor 3,4 Lead Out Part 5,6 End Face Electrode

Claims (11)

[Claims] 1. A conductor having a plurality of turns is provided in an insulator, and the diameter of each turn portion of the conductor is gradually changed from one end to the other end, and at least each turn portion is located in a different plane. Coil parts. 2. A structure in which each turn portion of the conductor is formed in the same plane from one end to the other end and is connected to an adjacent turn portion at a terminal end or a starting end of each turn portion.
Described coil parts. 3. The coil component according to claim 1, wherein the conductor has a three-dimensional spiral shape from one end to the other end. 4. The coil component according to claim 1, wherein each of the turns of the conductor has a circular shape. 5. The coil component according to claim 1, wherein each of the turns of the conductor has a rectangular shape. 6. The coil component according to claim 1, wherein the conductors are formed such that the conductor gaps are not visible between the turn portions when viewed from the large diameter turn portion side. 7. The coil component according to claim 1, wherein the cross-sectional shape of the conductor is rectangular, circular or semicircular. 8. The coil component according to claim 1, wherein the insulator is a non-magnetic substance. 9. The coil component according to claim 1, wherein the insulator is a magnetic substance. 10. The coil component according to claim 1, wherein the outer and inner insulators of the conductor are made of materials having different magnetic properties. 11. The coil component according to claim 10, wherein a non-magnetic material and a magnetic material are used as those having different magnetic properties.