JPH09190924A - Coil component and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the floating capacity by providing a conductor wherein the diameters of respective turn parts vary gradually from one end to the other end and the respective turn parts are positioned in different planes, and constituting partly an insulator with a magnet. SOLUTION: In a conductor 2, the diameters of respective turn part vary gradually from one end to the other end thereof, that is, it is a squared conductor like mosquito coil and the respective turn parts are positioned in different planes. Then, an outer insulator 1, an inner insulator 7 or end surface layers 8 and 9 are partly provided with a magnet 10 made of magnet material, and the rest thereof is almost made of one kind of material. In a coil component, at least a part of an insulator, that is, the outer insulator 1 and inner insulator 7 or the layers 8 and 9 are necessary to be made of magnet. In addition, the layer 9 is partly comprised of the magnet 10, and the outer insulator 1 or inner insulator 7 may be partly comprised of magnet.

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 for various electronic devices and communication devices, and a method of manufacturing the same.

[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 a ferrite magnetic layer and a coil conductor layer (for example, Japanese Patent Publication No.
39521).

In this laminated coil component, as shown in FIGS. 10 and 11, 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 is increased, and there is a problem in terms of productivity.
Since they are formed so as to face each other via the electrodes 2 and 14, there is a problem that the stray capacitance between the conductor patterns becomes large, and the self-resonance frequency of the coil component becomes small and the breakdown voltage is small.

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 coil conductor resistance, the entire thickness of the conductor pattern 13, The part with 15 and the part without 15 were very different from each other, and cracks were generated even after firing, and a coil component of stable quality could not be obtained.

An object of the present invention is to provide a coil component which eliminates the above-mentioned drawbacks of the prior art, is excellent in productivity, has a small stray capacitance and is excellent in electric characteristics, and a method for manufacturing the same.

[0008]

In order to solve the above-mentioned problems, the coil component of the present invention comprises a conductor consisting of a plurality of turns in the insulator or on the surface, and the diameter of each turn portion gradually changes from one end to the other end. In addition, at least each of the turn portions is provided with a conductor located in a different plane, and at least a part of the insulator is composed of a magnet.

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 is provided with a conductor consisting of a plurality of turns in an insulator or on a surface thereof, and the diameter of each turn portion gradually changes from one end to the other end and at least each turn. A coil having various electrical characteristics, which has conductors whose parts are located in different planes, and in which at least a part of the insulator is composed of a magnet, which is easy to produce and has a small stray capacitance between each turn part of the conductor. The parts can be easily obtained.

According to a second aspect of the present invention, a conductor having a plurality of turns is provided inside or on the surface of the insulator, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is located in a different plane. Equipped with a conductor
Further, an end face layer is provided on at least one of the upper and lower ends of the insulator, and a magnet is provided on at least a part of the insulator or the end face layer.
That is, an end face layer is further added to the coil component according to claim 1, a part of the end face layer may be a magnet, and it is easy to obtain a coil component which is easy to produce and has various excellent characteristics. It is possible to achieve the effect of the magnet, or to facilitate the formation of the magnet portion.

According to a third aspect of the present invention, one of a step of forming an insulator having a conical or pyramidal hollow portion provided in the center and a step of forming a cone or pyramidal insulator, or Both steps, and the inner surface of the insulator having a hollow portion or the surface of the conical or pyramidal insulator is made up of a plurality of turns, and the diameter of each turn portion gradually changes from one end to the other and at least each turn portion is different. A step of forming a conductor so as to be located in a plane, and forming an end face layer on at least one of the upper and lower end faces of an insulator having a hollow portion or a conical or pyramidal insulator, and a part of the end face layer Is a manufacturing method which mainly includes a step of forming an end face layer made of a magnet material, which facilitates production and particularly facilitates formation of a magnet portion.
Further, the obtained coil component has a small stray capacitance between each turn portion of the conductor, and can be easily adjusted to various electric characteristics.

The coil component of the present invention comprises a conductor having a plurality of turns inside or on the surface of the insulator, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is located in a different plane. And at least a part of the insulator is composed of a magnet. Further, an end face layer is added to at least one of the upper and lower ends of the insulator, and in this case, at least a part of the insulator or the end face layer is composed of a magnet. Basically, any coil component is equipped with a conductor consisting of multiple turns inside or on the surface of the insulator, and the diameter of each turn part gradually changes from one end to the other, and at least each turn part is in a different plane. A conductor is located and at least a portion of the insulator is a magnet.

For example, as an example of the shape of the conductor in which the diameters of the respective turn portions gradually change from one end to the other end and at least the respective turn portions are located in different planes,
The insulator has a conductor composed of a plurality of turns, and the conductor 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 respective turn portions are located in different planes. Furthermore, each turn part has a plurality of turns. That is, one end of the conductor is formed with a small diameter circle, and the diameter is gradually increased toward the other end side,
Each turn part rises or falls at the terminal end or the starting end and is connected to an adjacent turn part. Moreover,
Each turn part is composed of a plurality of turns. 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.
In this case, each turn portion means a conductor existing in the same plane. Further, as another example of the conductor, there is a three-dimensional spiral coil in which the diameter gradually increases from one end to the other end and the positions are all located in different planes.

Embodiments of the present invention will be further described below with reference to the drawings. FIG. 1 shows a cross-sectional view of a coil component of the present invention, in which the conductor 2 is located on the inner surface of the outer insulator 1 or the surface of the inner insulator 7. Here, the conductor 2 refers to a conductor in which the diameter of each turn portion gradually changes from one end to the other end and at least each turn portion is located in a different plane. Part of the outer insulator 1, the inner insulator 7 or the end face layers 8 and 9 has a magnet 10 made of a magnetic material, and most of the rest is made of one kind of material. In the example shown in FIG. 1, a part of the end face layer 9 is the magnet 10. The outer insulator 1, the inner insulator 7, or the end surface layers 8 and 9 may be nonmagnetic or magnetic. The example of FIG. 1 shows the case where the end face layers 8 and 9 are provided. In the coil component of the present invention, it is necessary that at least a part of the insulator, that is, the outer insulator 1 and the inner insulator 7, or the end face layers 8 and 9 is a magnet, but in the case of FIG. It is a coil component constituted by 10, and a part of the outer insulator 1 or the inner insulator 7 may be constituted by a magnet.

As the non-magnetic material forming the outer insulator 1 and the inner insulator 7 or the end surface layers 8 and 9, organic insulating materials such as glass epoxy and polyimide, inorganic materials such as glass, glass ceramics and ceramics are used. Any electrically insulating material such as an insulating material may be used.

On the other hand, as the magnetic material, NiZn system or Ni is used.
Any generally known ferrite material having a high magnetic permeability, such as ZnCu, may be used. Here, in the present invention, the term "magnetic material" refers to a magnetic material having excellent soft magnetic characteristics, and a hard magnetic material such as a magnet is referred to as a magnet.

When the outer insulator 1, the inner insulator 7 or the end face layers 8 and 9 are made of a magnetic material, the inductance value can be increased, and when they are made of a non-magnetic material, a small inductance value cannot be obtained. The self-resonant frequency becomes higher and the usable frequency band becomes wider.

Any material may be used as the material of the conductor 2 or the extraction electrodes 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, but 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, solder cracking, etc. Specifically, use the same conductive material as the extraction electrodes 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. Improves heat resistance because it is fired using the formation process and electrically connected,
It is also conceivable to adopt a configuration corresponding to this thick film forming process.

The coil component of the present invention comprises a conductor 2 having a plurality of turns on the inside or surface of the insulator, that is, on the surface of the outer insulator 1 or the inner insulator 7, and the diameter of each turn portion gradually increases from one end to the other end. Different, at least each turn portion has a conductor 2 located in a different plane,
Moreover, at least a part of the insulator (the outer insulator 1 or the inner insulator 7) is composed of a magnet.
Furthermore, the structure has an end face layer on at least one of the upper and lower ends of the insulator. In this case, in addition to the outer insulator 1 or the inner insulator 7, at least a part of the end face layers 8 and 9 may be composed of magnets. Good.

As another example, FIG. 2 shows an example in which at least a part of the inner insulator 7 is constituted by the magnet 10. Other configurations are the same as those shown in FIG. Other examples include those in which a part of the outer insulator 1 is composed of the magnet 10, or a plurality of parts are composed of the magnet 10.

Next, the coil component shown in FIG. 3 will be described. In the structure shown in FIG. 3, the outer insulator 1 and the inner insulator 7 are made of materials having different magnetic properties. That is, in FIG. 3, when the outer insulator 1 is made of a magnetic material and the inner insulator 7 is made of a non-magnetic material as the outer outer insulator 1 and the inner inner insulator 7 with respect to the conductor 2, a coil component is obtained. As a result, the inductance value is smaller than that in the case where both the outer insulator 1 and the inner insulator 7 are made of a magnetic material, but the DC superposition characteristic can be significantly improved. That is, even if the current value is changed, the change in the inductance value can be reduced, and the allowable current value can be increased.

An extreme example in which the outer insulator 1 or the inner insulator 7 is made of a non-magnetic material is the case where either the outer insulator 1 or the inner insulator 7 is removed and replaced with air. In this case, the conductor 2 may be formed on the surface of the outer insulator 1 or the inner insulator 7, whichever is present.

Further, both the outer insulator 1 and the inner insulator 7 are magnetic bodies, and by making them magnetically different in magnetic flux density, it is possible to improve the DC superposition characteristic.

Further, both the outer insulator 1 and the inner insulator 7 are magnetic bodies, and by making them magnetically different in magnetic permeability, coil components having the same conductor structure but different inductance values can be obtained. You can In this case, there is no particular limitation on the magnitude relationship of the magnetic permeability between the outer insulator 1 and the inner insulator 7.

As described above, the outer insulator 1 and the inner insulator 7
By appropriately selecting the magnetic properties of the above, the inductance value of the coil component can be arbitrarily selected, and the leakage flux or the DC superimposition characteristics can be controlled freely.

Similarly, by selecting various materials having different magnetic properties also for the end surface layers 8 and 9, the inductance value as a coil component can be arbitrarily selected, and the leakage flux or DC It goes without saying that the superposition characteristics can be controlled freely.

By appropriately selecting various residual magnetic flux densities of the magnet 10, it is possible to freely control the electric characteristics of the coil component of the present invention. For example, as shown in FIG. 3, when a part of the end face layer 9 is composed of the magnet 10, the magnetic flux generated by the magnet 10 causes the outer insulator 1, the inner insulator 7 and the end face layers 8 and 9 to be magnetic. It is possible to reach an effective saturation state. for that reason,
It is possible to control the current value at which a large inductance value is desired to be generated. That is, a large inductance value can be generated for a specific current value flowing through the conductor 2.

The cross-sectional shape of the conductor 2 is not limited to a flat rectangular shape, but the cross-sectional area of the conductor 2 can be increased to reduce the conductor resistance and can be used for a large current. In this case, as the cross-sectional shape of the conductor 2, various shapes such as a triangle, a circle, an ellipse, a semicircle, a polygon, and an oval are possible. To obtain the conductor 2 having such a cross-sectional shape, for example, the outer insulator 1
It is possible to realize the conductor 2 having a triangular cross-section by providing a stepped step portion on the inner surface of the substrate, applying a conductive paste to the step portion, curing the paste, and then sintering the paste.

Further, although the circular shape has been shown as an example of the overall shape of the conductor 2, a square shape or the like may be used. In other words, the prismatic shape is originally preferred as the surface-mount type coil component, and in the prismatic coil component, it is necessary to form the square-shaped turn portion that is full of the outer shape of the coil component by forming the prismatic turn portion. Will be possible. In order to obtain such a conductor 2, for example, the outer insulator 1 is formed, the conductor 2 is formed on the inclined surface of the hollow portion, and then the hollow portion is filled with the insulator. And inner insulator 7
A rectangular turn portion can be formed in the insulator formed by.

As described in many examples above, the diameter of each turn portion gradually changes from one end to the other in the insulator or the surface formed by the outer insulator 1 and the inner insulator 7, and at least each turn portion is Since the conductors 2 located in different planes are continuously formed, unlike the conventional laminated structure, the production is easy and the yield can be improved. Since they do not face each other, the generation of stray capacitance is minimized,
It is possible to prevent that the self-resonance frequency becomes small and a high attenuation cannot be obtained in a wide band when it is used as a filter or the like, and it is possible to obtain a coil component that is remarkably excellent in terms of quality and performance.

In the above embodiment, only the surface mounting type having the end face electrodes 8 and 9 provided at both ends has been described. However, an insulator in which pin terminals are implanted or an end face electrode is used instead of the end face electrode. It is also possible to form a lead-type coil component in which cap-shaped electrodes having terminals are fitted and coupled to both ends of an insulator.

Next, a method of manufacturing the coil component of the present invention will be described. The method for manufacturing a coil component of the present invention includes one or both of a step of forming an insulator having a conical or pyramidal hollow portion provided in the center and a step of forming a conical or pyramidal insulator. The process and the inner surface of the insulator having the hollow portion or the surface of the cone-shaped or pyramid-shaped insulator is made up of a plurality of turns, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is in a different plane. And a step of forming a conductor so as to be located on the upper and lower end surfaces of an insulator having a hollow portion or an insulator having a conical shape or a pyramidal shape, and the end surface layer is mainly formed of a magnet. A method of manufacturing a coil component, the method including:

A conductor is formed in the insulator or on the surface thereof, in which the diameter of each turn portion gradually changes from one end to the other end and at least each turn portion is located in a different plane. That is, since the conductor is formed on the inclined or stepped surface of the insulator, the coil component can be obtained with excellent productivity.

Next, a more detailed method of manufacturing the coil component of the present invention will be described with reference to the drawings.

4 to 9 are sectional views showing the method of manufacturing the coil component of the present invention in the order of steps. First, as shown in FIG. 4, a three-dimensional spiral winding step portion is formed on the inner surface of the hollow outer insulator 1 having a conical or pyramidal hollow portion 11 formed in the center, and a plurality of step portions are formed in this step portion. It consists of turns and the diameter of each turn part gradually changes from one end to the other,
An outer insulator 1 is formed having an inner surface on which the conductors 2 can be formed such that at least each turn portion lies in a different plane.

Even if the shape of the inner surface is a simple conical surface or a pyramidal surface, as described above, the conductor 2 is composed of a plurality of turns, and the diameter of each turn portion gradually changes from one end to the other, and at least The conductor 2 may be formed on this inner surface so that the turn portions are located in different planes. On the other hand, in the case of a step surface instead of a simple inclined surface, for example, when the conductor 2 is formed at the corner of the step surface, it is composed of a plurality of turns as a whole, and the diameter of each turn portion gradually increases from one end to the other end. The conductors 2 need to be formed so that they are different and at least each turn portion is located in a different plane.

As a more specific example of the conductor 2, each turn portion of the conductor 2 is formed in the same plane from one end to the other end, and is connected to an adjacent turn portion at the end or start end of each turn portion. Alternatively, the conductor may have a three-dimensional spiral winding from one end to the other.

As a method for forming the hollow outer insulator 1 having the inner surface having the above-described shape, a slurry-like insulator is poured onto a support having convex portions capable of engaging with the inner surface, and after drying, By separating from this support, a specific hollow portion 11 can be formed in the insulator. As another method, similarly to the above, a slurry-like insulator is poured on a flat support to form a smooth sheet-like insulator, and then a shape for forming the predetermined hollow portion 11 is formed. Hollow part 11 specific to the insulator with the mold
It is a method of forming. Furthermore, the hollow outer insulator 1 having the specific hollow portion 11 can be similarly formed by a generally known powder molding method. By any method, as shown in FIG. 4, the hollow outer insulator 1 having the above-described specific inner surface can be formed. Moreover, as described above, the inner surface may be either a slope or a step-like slope.

Next, as shown in FIG. 5, a specific hollow portion 11 is formed.
The conductor 2 is formed on the inner surface of the hollow portion 11 of the outer insulator 1 having a spiral step shape. The conductor 2 is composed of a plurality of turns, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is located in a different plane. As the shape, as described above, there is a shape in which the central portion of the mosquito coil incense-shaped conductor 2 is pulled down into a trumpet shape, or a shape in which concentric ones are connected.

As shown in FIG. 6, the outer insulator 1 on which the conductor 2 is formed has the extraction electrode 3 formed in advance on the bottom surface of the outer insulator 1 so that it can be joined to the conductor end of the conductor 2 on the smaller conductor diameter side.
Moreover, the end face layer 9 which is partially formed of the magnet 10 is joined.

Next, as shown in FIG. 7, the hollow portion 11 formed of the outer insulator 1 and the end face layer 9 is filled with an insulator to form the inner insulator 7.

As shown in FIG. 8, as in the case of forming the end face layer 9, the bottom face of the outer insulator 1 and the opposite face on which the extraction electrode 3 is formed are joined to the conductor end of the conductor 2 on the larger conductor diameter side. An end face layer 8 on which possible extraction electrodes 4 have been formed in advance is joined to the end faces of the outer insulator 1 and the inner insulator 7.

Further, as shown in FIG. 9, end face electrodes 5 and 6 are formed on the two surfaces of the chip-shaped component. By firing the obtained laminate, a coil component can be obtained. However, baking may be performed without forming the end face electrodes 5 and 6. That is, a method in which the end electrodes 5 and 6 are not formed is fired, and the end electrodes 5 and 6 are formed after firing. Explaining one example of the forming method in this case, a conductor layer is formed in the same shape as the end face electrode shown in FIG. 9 and is fired once. Thereafter, using this conductor layer as an electrode, nickel plating and solder or tin plating are performed. Finally, the end electrodes 5 and 6 have a three-layer structure of nickel and solder or tin formed by electroplating and an underlying conductor layer formed by firing.

The outer insulator 1, inner insulator 7 or end face layers 8 and 9 described above can be formed by a generally known green sheet molding method, printing method, dipping method, powder molding method or spin coating method. it can. The conductor 2 or the extraction electrodes 3 and 4 are generally printed by a printing method, but a method of patterning using a laser, a method of transferring a conductor previously formed in a predetermined shape with a mold, a dropping method, a potting method or a thermal spraying method. But it's okay.

The coil component obtained by the manufacturing method of the present invention is a coil component excellent in heat resistance, and thus can be easily modularized. For example, a predetermined wiring layer may be formed on a ceramic substrate such as an alumina substrate or a ferrite substrate, and wiring of the substrate and the end face electrodes 5 to 6 of the coil component may be simultaneously connected to be integrated or assembled.
In this case, a thin module can be obtained because it is possible to open a window at a predetermined position on the substrate and connect the end face electrodes 5 to 6 on the side surface of the coil component and the wiring on the ceramic substrate. In this case, an ordinary thick film forming process using a generally known ceramic substrate can be applied. The end face electrodes 5 to 6 of the coil component are not based on the assumption of soldering, but may be fired to be electrically connected.

The two terminals of the conductor 2 forming the above coil are formed on the end face of the chip part and end face electrodes 5 to 6 are formed.
It is in a state of being electrically connected to. That is, the uppermost and lowermost parts of the conductor 2 are provided with the extraction electrodes 3 to 4 for electrically connecting to the end face electrodes 5 to 6 and are connected to the end face electrodes 5 to 6.

The paste for forming each of the above layers is
Solvents such as butyl carbitol, terpineol, and alcohol, binders such as ethyl cellulose, polyvinyl butyral, polyvinyl alcohol, polyethylene oxide, and ethylene-vinyl acetate; and sintering aids such as various oxides and glasses. In addition, a plasticizer or a dispersant such as butylbenzyl phthalate, dibutyl phthalate, and glycerin may be added.
Each layer is formed using a kneaded material obtained by mixing these. A coil component is obtained by firing a laminate of these in a predetermined structure as described above. When producing a green sheet, various solvents having excellent evaporating properties, for example, butyl acetate, methyl ethyl ketone, toluene, alcohol, and the like are desirable in place of the above-mentioned solvents.

The firing temperature range is from about 800 ° C. to 13
It is in the range of 00 ° C. In particular, it depends on the conductor material. For example, when silver is used as the conductor material, it is necessary to be around 900 ° C., and at 950 ° C. for an alloy of silver and palladium, and nickel or palladium is used as the conductor material for firing at a higher temperature. .

Next, more specific examples of the present invention will be described. (Example 1) 8 g of butyral resin, 4 g of butylbenzyl phthalate, 24 g of methyl ethyl ketone and 24 g of butyl acetate were mixed with 100 g of NiZnCu-based ferrite powder, and kneaded with a pot mill to prepare a ferrite slurry.

Using this slurry, a ferrite green sheet having a thickness of 0.2 mm was prepared after drying with a coater. The green sheet was formed on a PET film.

Similarly, 100 g of barium ferrite powder
On the other hand, 8 g of butyral resin, 4 g of butylbenzyl phthalate, 24 g of methyl ethyl ketone and 24 g of butyl acetate were mixed and kneaded using a pot mill to prepare a magnet slurry. Using this slurry, a magnet green sheet having a thickness of 0.2 mm was produced after drying using a coater.

Three ferrite green sheets prepared above were stacked and laminated. A hot press is used for laminating the ferrite green sheets, and the platen temperature of the hot press is 100.
The temperature was set to 0 ° C and the pressure was 500 kg / cm ² . FIG.
The conductor 2 has a plurality of turns formed on the inner surface of the hollow outer insulator 1 as shown in FIG. 2 so that the diameter of each turn portion gradually changes from one end to the other and at least each turn portion is located in a different plane. Using a die having a shape for forming a predetermined inner surface capable of forming a predetermined inner surface on the laminated ferrite green sheet using a puncher, a conical hollow A hollow outer insulator 1 having a central portion was formed.

Next, as shown in FIG. 5, using a commercially available silver paste and a printing machine, the inner surface of the outer insulator 1 has a plurality of turns, and the diameter of each turn portion gradually changes from one end to the other, and at least The conductor 2 was formed so that each turn portion was located in a different plane. The printing method was such that the silver paste was left at the corners of the stepped slope on the inner surface, as in the case of generally known through-hole printing, by suctioning from the surface opposite to the printed surface of the outer insulator 1.

Next, as shown in FIG. 6, the end face layer 9 was prepared by laminating the ferrite green sheet (having a thickness of 0.2 mm) and the magnet green sheet (having a thickness of 0.2 mm) prepared previously. Further, using the same silver paste and printing machine as described above, the extraction electrode 3 was formed, and the end face layer 9 and the outer insulator 1 having the conductor 2 formed thereon were bonded together.

Further, as shown in FIG. 7, the ferrite slurry described above was poured into the inner surface of the outer insulator 1, that is, the hollow portion 11 to prepare a substantially flat ferrite green sheet. That is, the inner insulator 7 was formed by this filling.

Next, as shown in FIG. 8, using the same silver paste and printing machine as described above on the ferrite green sheet (thickness: 0.2 mm) prepared above, a plurality of turns were formed on the same plane, and the extraction electrode was formed. 4 was formed. That is, the end face layer 8
The extraction electrode 4 was formed on. Further, the end face layer 8 and the outer insulator 1 having the inner insulator 7, the conductor 2 and the like formed thereon were bonded together.

Further, end face electrodes 5, 6 as shown in FIG.
Was formed using a commercially available silver paste and was fired under the condition of holding at 900 ° C. for 2 hours.

No defects such as peeling, cracking and warping were found in the coil component of the present invention obtained by the above method.
When various electric characteristics were measured using an impedance analyzer or the like, it was found that the coil component had excellent characteristics.

As described above, according to the coil component of the present invention, a coil component having excellent electrical characteristics can be obtained with a smaller number of layers than a conventional laminated coil component.

Example 2 As in Example 1, NiZnC
6 g of butyral resin, 4 g of butylbenzyl phthalate and 50 g of butyl acetate were mixed with 100 g of the u-based ferrite powder, and kneaded using a pot mill to prepare a ferrite slurry.

Using this slurry, a plurality of turns are formed on the inner surface of the hollow outer insulator 1 as in Example 1, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is different. A ferrite green sheet having a thickness of 0.6 mm after drying is prepared using a coater on a sheet-shaped polyimide having a shape for forming a predetermined inner surface capable of forming the conductor 2 so as to be located in a plane. Then, the outer insulator 1 was formed.

Next, as in Example 1, the conductor 2 was formed on the inner surface of the outer insulator 1. Further, as shown in FIGS. 6 to 9, using the same method and the same magnet green sheet as in Example 1, the end face layer 9 having the magnet 10, the inner insulator 7, the end face layer 8, the extraction electrodes 3, 4 were used. Then, the end face electrodes 5, 6 and the like were formed and fired under the condition of holding at 900 ° C. for 2 hours.

No defect such as peeling, cracking or warpage was found in the coil component of the present invention obtained by the above method.
When various electric characteristics were measured using an impedance analyzer or the like, it was found that the coil component had excellent characteristics.

As described above, according to the coil component of the present invention, a coil component having excellent electrical characteristics can be obtained with a smaller number of laminations than a conventional laminated coil component. Further, this method is advantageous in terms of man-hours since the outer insulator 1 is formed in one step as compared with the method shown in the first embodiment.

[0069]

As is apparent from the above description, the coil component of the present invention is excellent in productivity because it is not a laminated structure, and also has a virtual conical or pyramidal curved surface or actual surface in or on the insulator. Since the conductor is located on the slope or stepped slope, the height can be kept low, and the stray capacitance between the conductor turn parts hardly occurs, and the electrical characteristics should be excellent. And has great industrial value.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a coil component of the present invention.

FIG. 2 is a cross-sectional view of another embodiment.

FIG. 3 is a cross-sectional view of still another embodiment.

FIG. 4 is a sectional view showing a method for manufacturing a coil component of the present invention in a state where an outer insulator is formed.

FIG. 5 is a sectional view showing a state where the conductor is formed.

FIG. 6 is a cross-sectional view showing a state in which the same end face layer is formed.

FIG. 7 is a sectional view showing a state where the inner insulator is formed.

FIG. 8 is a cross-sectional view showing a state where the other end face layer is formed.

FIG. 9 is a cross-sectional view showing a state where the end face electrode is formed.

FIG. 10 is a schematic perspective view showing a conventional coil component.

FIG. 11 is an exploded perspective view of the same.

[Explanation of symbols]

 1 Outer Insulator 2 Conductor 3,4 Extraction Electrode 5,6 End Face Electrode 7 Inner Insulator 8,9 End Face Layer 10 Magnet 11 Hollow Part

Claims (3)

[Claims] 1. A conductor comprising a plurality of turns inside or on the surface of the insulator, wherein the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion is located in a different plane. A coil component in which at least a part of an insulator is composed of a magnet. 2. A conductor comprising a plurality of turns inside or on the surface of the insulator, wherein the diameter of each turn portion gradually changes from one end to the other and at least each turn portion is located in a different plane, and further insulated. A coil component having an end face layer on at least one of the upper and lower ends of the body and having at least a part of the insulator or the end face layer made of a magnet. 3. One or both of the step of forming an insulator having a conical or pyramidal hollow portion provided in the center and the step of forming a conical or pyramidal insulator, and the hollow portion. The inner surface of the insulator having a plurality of turns on the inner surface of the insulator or the surface of the cone-shaped or pyramid-shaped insulator has a diameter that gradually changes from one end to the other end, and at least each turn portion is located in a different plane. An end surface layer is formed on at least one of the upper and lower end surfaces of the step of forming a conductor and an insulator having a hollow portion or an insulator having a conical shape or a pyramidal shape, and the end surface layer is partly made of a magnetic material. And a step of forming a layer.