JPH09260141A - Coil component and method of manufacturing the same - Google Patents

Abstract

(57) Abstract: The present invention relates to a coil component and a method of manufacturing the same, and in particular, to provide a coil component having excellent characteristics. In a coil component having a conductor (2) made up of a plurality of turns in an insulator, the diameter of each turn portion is gradually different from one end to the other on the inner surface of a hollow outer insulator (1), and at least each turn portion is The conductor 2 and the end face layer 8 located on different planes are provided with windings 10. With this configuration, the stray capacitance between the conductors is small, and the direct current resistance of the conductor is also small, and the electrical characteristics are excellent, and the structure can be easily manufactured with a small number of steps.

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 20 is formed by printing on a half of a ferrite green sheet 24, and a portion without the ferrite layer 20 and a portion of the ferrite layer 20. An L-shaped conductor pattern 21 is formed by printing on, and about half the ferrite layer 22 of the green sheet 24 is printed on the conductor pattern 21, and the ferrite layer 20 and the ferrite layer 20 are continuous so as to be continuous with the conductor pattern 21. A U-shaped conductor pattern 23 is printed on a part of 22 and this step is repeated several times to collectively fire a laminate of a ferrite green sheet 24 as the uppermost layer, and end face electrodes 25 are formed on both ends of this laminate. 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 20, 22 and conductor patterns 21, 23 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 with 0, 22 interposed, there is a problem that the stray capacitance between the conductor patterns becomes large, and the self-resonant frequency of the coil component becomes small and the withstand 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 resistance of the coil conductor, the entire thickness of the conductor pattern 21 is reduced. , 23, and the portions not having 23, were largely different from each other, and cracks were generated even after firing, and a coil component of stable quality could not be obtained.

The present invention eliminates the above-mentioned conventional defects, and provides a coil component excellent in productivity and excellent in electrical characteristics such as a small stray capacitance and a large inductance, and a manufacturing method thereof. To aim.

[0008]

In order to solve the above problems, the coil component of the present invention comprises a plurality of turns in the insulator or on the surface thereof, and the diameter of each turn portion gradually changes from one end to the other end, and at least each turn. In this structure, the conductor and the winding are located in different planes.

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 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, and at least each turn portion is different. A structure having a conductor and a winding located in a plane, and having excellent electrical characteristics such as easy production and small stray capacitance between conductor turn parts and large inductance. You can

According to a second aspect of the present invention, there is provided an end face layer on at least one of the upper and lower ends of the insulator, and a winding is provided in the end face layer. The properties or mechanical strength can also be improved. Further, by forming the winding in the end face layer, the electrical characteristics of the winding portion can be improved or sufficient insulation can be secured. Since the winding is provided in the end face layer, the coil component can be manufactured easily and has excellent characteristics.

According to a third aspect of the present invention, one end of the winding is connected to one end of the conductor, and the end face electrode is connected to the winding and the other terminal of the conductor, that is, in the winding. A sufficient inductance value can be secured and adjustment can be performed in the conductor portion, and a coil component with a narrow intersection can be realized.

The invention described in claims 4 and 5 is
By using a magnetic material or a non-magnetic material around the winding, windings with various electrical characteristics can be obtained, and the characteristics of the entire coil component can be freely controlled. Further, when a non-magnetic material is used, the self-resonant frequency can be increased, so that the usable frequency band can be increased.

According to a sixth aspect of the present invention, the insulating material inside the winding and the insulating material outside the winding have different magnetic properties, and windings having various electrical characteristics can be obtained. The characteristics of the entire coil component can be controlled freely.

According to a seventh aspect of the present invention, the winding is composed of a metal wire insulated with an inorganic material, and it becomes possible to secure the heat resistance of the coil component, and the firing is performed at a high temperature in terms of the manufacturing method or mounting. Can be performed, and a coil component having excellent electrical characteristics can be realized.

According to an eighth aspect of the present invention, there is provided a boundary between the winding and the conductor, and the boundary is a non-magnetic material. Mutual interference or magnetic coupling between the conductor and the winding. Can be eliminated, and a coil component with excellent electrical characteristics can be realized.

According to a ninth aspect of the present invention, there are provided a step of forming a hollow insulator having a conical or pyramidal hollow portion in the center and a step of forming a conical or pyramidal insulator. Either one or both steps, and the inner surface of the hollow insulator 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 This is a method for manufacturing a coil component, which comprises a step of forming a conductor so that the turn portions are located in different planes and a step of incorporating a winding. The coil component is easy to produce, and the obtained coil component is each turn portion of the conductor. The floating capacitance between them can be small and the electrical characteristics can be excellent.

According to a tenth aspect of the invention, in addition to the ninth aspect of the invention, an end face layer is formed on at least one of the upper and lower end faces of the hollow insulator or the conical or pyramidal insulator. Is added, and the structure is such that the surface mountability and strength of the obtained coil component or the winding portion and the conductor portion can be easily integrated.

The coil component of the present invention comprises a plurality of turns in the insulator or on the surface thereof, and the diameter of each turn part gradually changes from one end to the other end, and at least each turn part is located in a different plane and a winding. It is a coil component having. As an example of the shape of the conductor that constitutes the coil component, that is, the winding method, there is a conductor consisting of multiple turns in an insulator, and this conductor is a circle in which the diameter of each turn gradually increases from one end to the other end. The turn portions are formed on different planes.
In other words, one end of the conductor is formed as a circle with a small diameter, and a circle whose diameter gradually increases toward the other end, and each turn portion rises or falls at the end or start end and is adjacent to the next turn portion. Is connected to Therefore, each turn part is located in the same plane, and adjacent turn parts are located in different plane parts depending on rising and falling parts,
Moreover, the diameters are set to be different. There are about one turn in the same plane, where each turn means a conductor present in the same plane.

Further, as another example of the shape of the conductor, similarly, a conductor having a plurality of turns is provided in the insulator, and the diameter of the conductor gradually increases from one end to the other end, and the conductors are located in different planes. There is a three-dimensional spiral wound located.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a sectional view of a coil component of the present invention. The insulator comprises a portion of the outer insulator 1 located outside the conductor 2 and a portion of the inner insulator 7 located inside the conductor 2. The insulators, that is, the outer insulator 1 and the inner insulator 7 further have end face layers 8 and 9 on the upper and lower end faces thereof.
The winding 10 is built in. In addition, the winding 10 refers to the whole winding wire around which a conductive wire is wound.

As shown in FIG. 1, one end of the conductor 2 and the winding 10
One end of which is connected, and conductor 2 and winding 10
The terminals which are not connected are connected to the extraction electrodes 3 and 4, respectively. The extraction electrodes 3 and 4 are further disposed on the side surfaces of the outer insulator 1 and the end surface layers 8 and 9, respectively.
Is connected to Here, the insulator (the outer insulator 1 and the inner insulator 7) or the end face layers 8 and 9 is made of one kind of material, and the insulator or the end face layers 8 and 9 may be a non-magnetic substance or a magnetic substance. It may be.

The non-magnetic material may be any electrically insulating material such as an organic insulating material such as glass epoxy or polyimide, or an inorganic insulating material such as glass, glass ceramics or ceramics. 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 insulators (outer insulator 1 and inner insulator 7) or the end face layers 8 and 9 are magnetic substances, the inductance value can be increased, and when they are non-magnetic substances, a large inductance value can be obtained. I can't do that,
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 it is generally preferable 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 surface 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. 2 will be described. The thing shown in FIG. 2 is the outer insulator 1 which comprises an insulator.
And the inner insulator 7 having different magnetic properties. When the outer insulator 1 is made of a magnetic material and the inner insulator 7 is made of a non-magnetic material, the coil component has a smaller inductance value than the case where the insulator is made of a magnetic material. Can be greatly 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 eliminated and air is used. 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, by making both the outer insulator 1 and the inner insulator 7 magnetic, and having magnetically different magnetic flux densities, 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 connector 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, the end face layers 8 and 9 and the winding 10
By properly choosing the magnetic properties of the insulator around
It goes without saying that the inductance value as a coil component can be arbitrarily selected and the leakage magnetic flux or the DC superposition characteristic can be freely controlled.

The cross-sectional shape of the conductor 2 is not limited to a flat rectangular shape, and the cross-sectional area of the conductor 2 can be increased to reduce the conductor resistance and can be used for 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.

Although an example of a circular shape has been shown so far as 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. To obtain such a conductor 2, for example, a pyramidal hollow portion is formed in an insulator, the conductor 2 is formed on the inclined surface of the hollow portion, and the hollow portion is filled with an insulator. The angular turn portion can be formed in the insulator.

As described in many examples above, the conductors 2 in which 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 are continuously formed in the insulator or on the surface. Unlike the conventional laminated structure, this structure facilitates production and improves yield, and minimizes stray capacitance because neighboring turn parts do not face each other with an insulator in between. It can be suppressed 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 the coil component can be remarkably excellent in terms of quality and performance.

In the above-described embodiment, only the surface mounting type having the end electrodes 5 and 6 provided at both ends has been described. However, an insulator in which pin terminals are implanted, or the end surface electrodes 5 and 5 are provided. Instead of 6, a cap-shaped electrode having terminals may be fitted and coupled to both ends of an insulator to form a lead type coil component.

Next, an example of the coil component of the present invention shown in FIG. 3 will be described. FIG. 3 shows the coil component of FIG. 2 in which a boundary portion 11 is further provided at the boundary between the end surface layer 8 having the winding 10 built therein and the insulator, that is, the outer insulator 1 and the inner insulator 7. By making the boundary portion 11 a non-magnetic material, the conductor 2 and the winding wire 10 can be magnetically separated, and an excellent coil component can be obtained.

The winding 10 is generally formed by winding a coated copper wire on a winding support, but in the case of the coil component of the present invention, a winding support other than the general winding 10 described above is used. You may use the metal wire which consisted of the inorganic material excellent in heat resistance, and also covered the coated copper wire with the inorganic insulator. In this case, it is possible to secure sufficient heat resistance, and it is possible to make a more excellent coil component that takes advantage of this heat resistance in terms of process or mounting.

Next, a method of manufacturing the coil component of the present invention will be described. A method for manufacturing a coil component according to the present invention comprises a step of forming a hollow insulator having a conical or pyramidal hollow portion in the center, that is, an outer insulator 1, and a conical or pyramidal insulator, That is, one or both of the steps of forming the inner insulator 7, and a plurality of turns on the inner surface of the outer insulator 1 or the surface of the inner insulator 7, the diameter of each turn portion gradually increases from one end to the other end. It is a method of manufacturing a coil component, which includes a step of forming the conductor 2 such that the conductors 2 are different and at least each turn portion is located in a different plane, and a step of winding. Alternatively, it is a method of manufacturing a coil component, which further includes the step of forming the end face layers 8 and 9 on at least one of the upper and lower end faces of the outer insulator 1 or the inner insulator 7.

As described above, although there is a difference in the presence or absence of formation of the insulator, that is, the outer insulator 1 and / or the inner insulator 7 or the end face layers 8 and 9, basically, as described above, the insulator or the surface is formed. In addition, the diameter of each turn portion gradually changes from one end to the other end, and at least each turn portion forms the conductor 2 and the winding 10 located in different planes. That is, since the conductor 2 is formed on the inclined surface 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 a 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 12 formed in the center, and a plurality of step portions are formed in this step portion. An outer insulator 1 made of turns and having an inner surface such that the diameter of each turn portion gradually changes from one end to the other end and at least the conductor 2 can be formed so that each turn portion is located in a different plane. Form.

Even if the shape of the inner surface is a simple conical surface or a pyramidal surface, as described above, the conductor 2 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 It 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 stepped surface instead of a simple inclined surface, for example,
When the conductor 2 is formed at the corner of the stepped surface, it is composed of a plurality of turns as a whole, 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. It is necessary to form the conductor 2 on the.

As a more specific example of the conductor 2, as described above, each turn portion of the conductor 2 is formed in the same plane from one end to the other end, and the turn portions adjacent to each other at the end or the start end of each turn portion. And the conductor 2 has a three-dimensional spiral shape from one end to the other end.

As a method of forming the hollow-body-shaped 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 12 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 12 is formed. Hollow part 12 specific to the insulator with the mold that has
It is a method of forming. Furthermore, a hollow body-shaped outer insulator 1 having a specific hollow portion 12 can be 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 a slope or a stepped surface.

Next, as shown in FIG. 5, the specific hollow portion 12
The conductor 2 is formed on the inner surface of the hollow portion 12 of the outer insulator 1 having a spiral step shape. The conductor 2 has 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 mentioned above, as mentioned 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 an end face on which a lead electrode 3 is formed in advance on the bottom surface of the outer insulator 1 so that the lead electrode 3 can be joined to the conductor end of the conductor 2 on the smaller conductor diameter side. Join the layers 9.

Next, as shown in FIG. 7, the hollow portion 12 formed by 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, similarly to the case where the end face layer 9 is formed, the extraction electrode 4 is provided on the bottom surface of the outer insulator 1 opposite to the end face layer 9 formed, and the winding 10 is built in. The end face layer 8 thus formed is joined. One end of the winding 10 is connected to the extraction electrode 4, and the other end is connected to the conductor 2.

Further, as shown in FIG. 9, end face electrodes 5 and 6 are formed on 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, the end face electrodes 5 and 6 not formed are fired, and the end face electrodes 5 and 6 are fired after firing.
It is a method of forming. Explaining one example of the forming method in this case, a conductor layer is formed in the same shape as the end face electrodes 5 and 6 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.

As described above, the winding wire 10 is configured to withstand the firing process. This uses a metal wire coated with a coating material mainly made of an inorganic material on a winding support body made of an insulator. However, in the case of a coated copper wire that is commonly used, the method is one in which the above-mentioned firing or the firing at the time of forming the end face electrode is not performed.

The outer insulator 1, the inner insulator 7 or the 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.

Since the coil component obtained by the manufacturing method of the present invention can be a coil component having excellent heat resistance, it 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 location on the substrate and connect the end electrodes 5 to 6 on the side surfaces of the coil component to 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 premise 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 have the extraction electrodes 3 to 4 for electrically connecting to the end face electrodes 5 to 6, and the end face electrode 5
Connected 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 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 A ferrite slurry was prepared by mixing 8 g of butyral resin, 4 g of butylbenzyl phthalate, 24 g of methyl ethyl ketone and 24 g of butyl acetate with 100 g of NiZnCu-based ferrite powder and kneading them using a pot mill.

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.

Three pieces of this ferrite green sheet were stacked and laminated. A hot press was used for lamination of the ferrite green sheets, the platen temperature of the hot press was set to 100 ° C., and the pressure was 500 kg / cm ² . The inner surface of the hollow outer insulator 1 as shown in FIG. 4 has 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 located in a different plane. Using a die having a shape for forming a predetermined inner surface on which the conductor 2 can be formed, a predetermined inner surface is formed on the laminated ferrite green sheet by using a puncher to form a conical shape. A hollow body-shaped outer insulator 1 having a hollow portion in the center was formed.

Next, using a commercially available silver paste and a printing machine, the inner surface of the outer insulator 1 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 has a different plane. The conductor 2 was formed so as to be located inside. 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 lead electrode 3 was formed on the ferrite green sheet (having a thickness of 0.2 mm) prepared above by using the same silver paste as described above and a printing machine. Further, 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 12 to prepare a substantially flat ferrite green sheet. That is, the inner insulator 7 was formed by this filling.

A rod-shaped ferrite was used as a winding support, and a winding wire 10 was produced using a silver wire which was insulation-coated with an inorganic material. This winding wire 10 was produced as shown in FIG. Of 0.2 mm) to form the end face layer 8. In addition, the extraction electrode 4 was separately formed on the end face layer 8 by using the same silver paste as described above and a printing machine. Furthermore, the outer insulator 1 on which the end face layer 8, the inner insulator 7, the conductor 2 and the like are formed
Pasted 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 observed in the coil component of the present invention obtained by the above method.
When various electrical 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) NiZnC as in Example 1
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, and at least each turn portion is different. A ferrite green sheet having a thickness of 0.6 mm after being dried 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 1a 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. 4 to 9, the end face layer 9, the inner insulator 7, the end face layer 8 including the winding 10, the extraction electrode 4, the end face electrodes 5, 6 and the like are formed in the same manner as in the first embodiment. And was fired under the condition of holding at 900 ° C. for 2 hours.

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

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

[0075]

As is apparent from the above description, the coil component of the present invention is excellent in productivity because it does not have a laminated structure, and moreover, in the insulator or on the surface, that is, the conical or pyramidal inclined surface or the stepped shape. Since the conductor is located on the surface, the height can be kept low, and the stray capacitance between the turn parts of the conductor hardly occurs, and the large inductance due to the winding can be obtained. It can be excellent and has great industrial value.

[Brief description of 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 showing another embodiment.

FIG. 3 is a sectional view of another embodiment.

FIG. 4 is a schematic cross-sectional view showing a method for manufacturing a coil component according to the present invention.

FIG. 5 is a schematic sectional view showing a method for manufacturing a coil component of the present invention.

FIG. 6 is a schematic cross-sectional view showing a method for manufacturing a coil component of the present invention.

FIG. 7 is a schematic cross-sectional view showing a method for manufacturing a coil component according to the present invention.

FIG. 8 is a schematic sectional view showing a method for manufacturing a coil component of the present invention.

FIG. 9 is a schematic cross-sectional view illustrating a method for manufacturing a coil component according to the present invention.

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 Winding 11 Boundary 12 Hollow Part

Claims (10)

[Claims] 1. A coil component comprising a plurality of turns in an insulator or on a surface thereof, the diameter of each turn portion gradually changing from one end to the other end, and at least each turn portion having a conductor and a winding located in different planes. 2. The coil component according to claim 1, wherein at least one of the upper and lower ends of the insulator has an end face layer, and the winding is provided in the end face layer. 3. The coil component according to claim 1, wherein one end of the winding is connected to one end of the conductor, and the end face electrode is connected to the other terminal of the winding and the conductor, respectively. 4. The coil component according to claim 1, wherein a magnetic material is provided around the winding. 5. The coil component according to claim 1, wherein the winding is made of a non-magnetic material. 6. The coil component according to claim 1, wherein the insulator inside the winding and the insulator outside the winding have different magnetic properties. 7. The coil component according to claim 1, wherein the winding is made of a metal wire insulated with an inorganic material. 8. The coil component according to claim 1, wherein a boundary portion is provided between the winding and the conductor, and the boundary portion is a non-magnetic material. 9. Either or both of a step of forming a hollow insulator having a conical or pyramidal hollow portion provided in the center and a step of forming a conical or pyramidal insulator. The inner surface of a hollow insulator or the surface of a cone-shaped or pyramidal-shaped 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 method of manufacturing a coil component, which includes a step of forming a conductor so as to be positioned and a step of incorporating a winding. 10. Either or both of a step of forming a hollow insulator having a conical or pyramidal hollow portion provided in the center and a step of forming a cone or pyramidal insulator. The inner surface of a hollow insulator or the surface of a cone-shaped or pyramidal-shaped 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. The step of forming the conductor so that it is positioned, the step of forming an end face layer on at least one of the upper and lower end faces of the hollow body-shaped insulator or the conical or pyramidal-shaped insulator, and the step of incorporating the winding. A method of manufacturing a coil component having the same.