JPH09186014A - Coil component and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen the floating capacitance so as to improve electric characteristics by varying the diameter of each turn gradually from one side to the other side thereby positioning several turns in different planes, and constituting each turn in each plane of plural turns consisting of conductors. SOLUTION: At the inner face of a hollow outer insulator 1a, a coil is arranged. The coil is made of a conductor, and the coil consists of plural turns, and each turn consists of plural turns. The diameters of several turn parts are varied gradually from one side to the other side of the coil, thus the several turns are positioned in different planes, and the element of the coil is a conductor 2. That is, the smallest turn on the side of one end of the conductor forms a circle with a small diameter within itself, and the turn of each turn part forms a larger circle as it goes to the side of the other end, and each turn part goes up or goes down at its terminal or its head to connect with the adjacent turn. Hereby, the floating capacitance between the turn parts of the conductor 2 scarcely occurs, and it can be made one excellent in electric property.

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. 11 and 12, a ferrite layer 12 is formed on one half of a ferrite green sheet 16 by printing, 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 patterns 13 and 15 is reduced. There was a large difference between the portion with and without the crack, and cracks were generated even after firing, and it was impossible to obtain a coil component of stable quality.

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 inside or on the surface of the insulator, and the diameter of each turn portion gradually changes from one end to the other end. At least the respective turn parts are located in different planes, and each turn part located in the same plane is composed of a conductor having a plurality of turns.

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 is provided. The parts are located in different planes,
Moreover, since each turn portion located in the same plane is composed of a conductor composed of a plurality of turns, it is easy to produce, and the stray capacitance between the turn portions of the conductor is small and the electrical characteristics can be excellent.

According to the second aspect of the present invention, the conductors formed by a plurality of turns of the respective turn portions located in the same plane are made of a non-magnetic material, which is easy to produce, and the floating between the turn portions of the conductor is easy. It can have a small capacity and excellent electrical characteristics.

According to a third 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 body-shaped insulator or the surface of the cone-shaped or pyramidal-shaped insulator is made up of a plurality of turns, and the diameter of each turn portion gradually differs from one end to the other, and at least each A method for manufacturing a coil component, which has a step of forming conductors so that the turn parts are located in different planes and each turn part located in the same plane is composed of a plurality of turns. In addition, the coil component has a small stray capacitance between each turn portion of the conductor and can have excellent electrical characteristics.

According to a fourth aspect of the invention, in addition to the third 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. The process of adding
It becomes possible to facilitate surface mountability, strength, or formation of end face electrodes of the obtained coil component.

The coil component of the present invention is provided with a conductor consisting of a plurality of turns in the insulator or on the surface, 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, Moreover, each turn portion located in the same plane is composed of a conductor having a plurality of turns.

For example, as an example of the shape of this conductor,
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 the 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.

Embodiments of the present invention will be further described below with reference to the drawings. FIG. 1 shows a sectional view of a coil component of the present invention, in which a conductor 2 is formed inside an insulator 1. Here, the insulator 1 or the end surface layers 3 and 4 is made of one kind of material, and the insulator 1 or the end surface layers 3 and 4 may be a non-magnetic material or a magnetic material.

Lead-out electrodes 5 and 6 are provided at respective ends of the conductor 2, and the lead-out electrodes 5 and 6 are connected to the insulator 1 or the end face electrodes 7 and 8 provided on both sides of the end face layers 3 and 4, respectively. Has been done.

As the non-magnetic material constituting the insulator 1 or the end face layers 3 and 4, electrically insulating materials such as organic insulating materials such as glass epoxy and polyimide, inorganic insulating materials such as glass, glass ceramics and ceramics, etc. Any material may be used as long as it has an insulating property.

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.

When the insulator 1 or the end surface layers 3 and 4 are magnetic bodies, the inductance value can be increased,
When a non-magnetic material is used, a large inductance value cannot be obtained, but the self-resonant frequency becomes high and the usable frequency band becomes wide.

Any material may be used as the material for the conductor 2 or the extraction electrodes 5, 6 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 7 and 8 may be made of a conductive material, but generally, it is desirable that the end face electrodes 7 and 8 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 5 and 6 for the bottom 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 a metal.

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 7, 8 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.

The coil component of the present invention is provided with the conductor 2 consisting of a plurality of turns in the insulator 1 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 portion is in a different plane. In addition, each turn part has a conductor 2 having a plurality of turns, and as shown in FIG. 1, the conductor 2 is formed by stacking mosquito coil incense-like conductors in the winding direction of the conductors and gradually changing their diameters. It is a stack.

Next, the coil component shown in FIG. 2 will be described. In FIG. 2, the insulator 1 has different magnetic properties on the outside and inside of the drawing. That is, in FIG. 2, the outer insulator 1a is made of a magnetic material, and the outer insulator 1a is an outer insulator 1a, and the inner is an inner insulator 1b.
If is made of a non-magnetic material, the insulator 1
Although the inductance value is smaller than that of the case where the element is made of a magnetic material, the DC superposition characteristics 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 of forming the outer insulator 1a or the inner insulator 1b with a non-magnetic material is the outer insulator 1a.
Alternatively, either of the inner insulators 1b may be removed and replaced with air. In this case, the conductor 2 may be formed on the surface of the outer insulator 1a or the inner insulator 1b, whichever is present.

Further, both the outer insulator 1a and the inner insulator 1b are magnetic bodies, and by making them have magnetically different magnetic flux densities, it is possible to improve the DC superposition characteristics.

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.

Similarly, by varying the magnetic properties of the end face layers 3 and 4, as described above, the inductance value is adjusted, the DC superposition characteristic is improved, the frequency band used is controlled, or the leakage magnetic flux is controlled. It is possible. Further, the end face layers 3 and 4 are important also as the portions where the end face electrodes 7 and 8 are formed, and the end face electrodes 7 and 8 may be formed by a non-magnetic material for the main purpose.

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 is increased to reduce the conductor resistance.
It can also be used for large currents. 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 inner surface of the outer insulator 1a is provided with a plurality of stepped recesses, and the recesses are coated with a conductive paste and cured, and then sintered. By doing so, the conductor 2 having a semicircular cross section can be realized.

Further, the shape of the conductor 2, that is, the overall coil shape may be a square shape as well as a circular shape. 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, a pyramidal hollow portion is formed in the insulator 1, the conductor 2 is formed on the stepped slope of this hollow portion, and the hollow portion is filled with an insulator. As a result, a rectangular turn portion can be formed in the insulator 1.

Next, the coil component shown in FIG. 3 will be described.
As shown in FIG. 3, the conductor 2 has a large diameter at both ends and a small diameter at the middle portion, and the diameter of each turn portion described so far gradually changes from one end to the other end.
At least each turn portion is located in a different plane, and each turn portion has a structure in which two conductors 2 each having a plurality of turns are combined.

As described in many examples above, the insulator 1
A structure in which the diameter of each turn portion gradually changes from one end to the other end in or on the surface, at least each turn portion is located in a different plane, and each turn portion has a plurality of turns of conductor 2 continuously formed. Therefore, unlike the conventional laminated structure, it is easy to produce and the yield can be improved, and since the neighboring turn parts do not face each other with the insulator 1 in between, the occurrence of stray capacitance can be minimized. Therefore, it can be prevented that the self-resonance frequency becomes small and a high attenuation cannot be obtained in a wide band when used as a filter or the like, so that the coil component can be remarkably excellent in terms of quality and performance.

In the above embodiment, only the surface mount type having the end face electrodes 7 and 8 provided at both ends has been described. However, the insulator 1 having the pin terminals implanted 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.

Next, a method of manufacturing the coil component of the present invention will be described. The method for manufacturing a coil component according to the present invention includes one 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. 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 multiple turns, and the diameter of each turn portion gradually differs from one end to the other, and at least each turn portion Forming conductors that are located in different planes and each turn is a plurality of turns, or further, at least one of the upper and lower end faces of the hollow insulator or the conical or pyramidal insulator. It is a manufacturing method of a coil component which further added a process of forming a layer.

As described above, although there is a difference in the presence or absence of the formation of the insulator or the end face layer, basically, as described above, the diameter of each turn portion in the insulator or the surface gradually increases from one end to the other end. Differently, at least each turn portion is located in a different plane and each turn forms a plurality of turns. That is, since the conductor is formed on the 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 10 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 concentric stepped portion 9a as shown in the figure is formed on the inner surface of the hollow outer insulator 1a having a conical or pyramidal hollow 9 formed at the center. The conductor 2 is formed in the staircase portion 9a so that the diameter of each turn portion gradually changes from one end to the other end, at least each turn portion is located in a different plane, and each turn portion has a plurality of turns. The outer insulator 1a having an inner surface that can be formed is formed.

As a method for forming the hollow outer insulator 1a having the inner surface having the above-mentioned 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 9 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 9 is formed. This is a method of forming a specific hollow portion 9 in an insulator with a mold that has this. Furthermore, a hollow body-shaped outer insulator 1a having a specific hollow portion 9 can be similarly formed by a generally known powder molding method. By either method, as shown in FIG. 4, it is possible to form the hollow outer insulator 1a having the specific inner surface described above.

Next, as shown in FIG. 5, the conductor 2 is formed on the stepwise inner surface of the hollow portion 9 of the outer insulator 1a having the specific hollow portion 9. In this conductor 2, 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. Its shape is
As described above, there are shapes such as concentric circular shapes or concentric angular shapes.

Further, as shown in FIG. 6, a portion of the conductor 2 formed on the stepwise inner surface in the same plane is separated into a plurality of turns. This allows the conductor 2 to consist of multiple turns,
The diameter of each turn part gradually differs from one end to the other,
At least the respective turn portions are located in different planes, and the respective turn portions located in the same plane are the conductor 2 having a plurality of turns. In the example shown in FIG. 6, the conductor 2 in the same plane exists in two planes, and the conductor 2 is formed by about 3 turns in the same plane.

Next, as shown in FIG. 7, the outer insulator 1a on which the conductor 2 is formed is provided with a lead electrode 6 on the bottom surface of the outer insulator 1a, which can be joined to the conductor end of the conductor 2 on the smaller conductor diameter side. The formed end surface layer 4 is joined.

Further, as shown in FIG. 8, the outer insulator 1
An inner insulator 1b is formed by filling the hollow portion 9 formed by a and the end surface layer 4 with an insulator.

As shown in FIG. 9, as in the case where the end face layer 4 is formed, a lead end that can be joined to the conductor end of the conductor 2 on the larger conductor diameter side on the face opposite to the face on which the lead electrode 6 is formed. The end face layer 3 on which the electrode 5 is formed in advance is bonded to the end faces of the outer insulator 1a and the inner insulator 1b.

Further, as shown in FIG. 10, end face electrodes 7 and 8 are formed on two surfaces of the chip-shaped component. By firing the obtained laminate, a coil component can be obtained. However, the firing may be performed without forming the end face electrodes 7 and 8. In other words, it is a method of firing a material in which the end face electrodes 7 and 8 are not formed and forming the end face electrodes 7 and 8 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. 10 and is fired once. Thereafter, using this conductor layer as an electrode, nickel plating and solder or tin plating are performed. Alternatively, as another method, after firing in the state of FIG. 9, barrel polishing is further performed, the same conductor paste as that for forming the extraction electrodes 5 and 6 as the end face electrode base layer is used, and the firing is performed. After that, nickel plating and solder or tin plating are applied in the same manner as described above. Finally, the end face electrodes 7 and 8 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 1a, the inner insulator 1b or the end face layers 3 and 4 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. Conductor 2
Alternatively, the extraction electrodes 5 and 6 are generally printed, but a pattern formation 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 spraying method may be used. .

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 surface electrodes 7 to 8 of the coil component may be simultaneously connected to be integrated or assembled.
In this case, it is possible to open a window at a predetermined position on the substrate and connect the end face electrodes 7 to 8 on the side surface of the coil component to the wiring on the ceramic substrate, so that a thin module can be obtained. In this case, an ordinary thick film forming process using a generally known ceramic substrate can be applied. The end surface electrodes 7 to 8 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 7 to 8 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 5 to 6 for electrically connecting with the end face electrodes 7 to 8, and the end face electrode 7
Connected to 8

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.

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 1a 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 end, and at least each turn portion is located in a different plane,
Moreover, each of the turn parts is formed into a die having a shape for forming a predetermined inner surface capable of forming the conductor 2 having a plurality of turns, and a puncher is used to form the laminated ferrite green sheet. A predetermined stepped inner surface was formed, and a hollow outer insulator 1a 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 1a 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 has a different plane. The conductor 2 was formed so as to be located inside, and each turn portion consisted of a plurality of turns. 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 1a.
Further, in order to make each turn part consist of a plurality of turns, a conductor formed on each step-like surface was separated by using a laser.

Next, as shown in FIG. 7, the lead electrode 6 was formed on the ferrite green sheet (having a thickness of 0.2 mm) prepared above by using the same silver paste and a printing machine as described above.
Further, the end face layer 4 and the outer insulator 1a having the conductor 2 formed thereon were bonded together.

Further, as shown in FIG. 8, the ferrite slurry described above was poured into the inner surface of the outer insulator 1a, that is, the hollow portion 9 to prepare a substantially flat ferrite green sheet. That is, the inner insulator 1b was formed by this filling.

Next, as shown in FIG. 9, the lead electrode 5 was formed on the ferrite green sheet (having a thickness of 0.2 mm) prepared above using the same silver paste and the same printing machine as described above.
That is, the extraction electrode 5 was formed on the end face layer 3. Further, the end surface layer 3 and the inner insulator 1b, the outer insulator 1a on which the conductor 2 and the like are formed were laminated.

Further, the end face electrodes 7 as shown in FIG.
8 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 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.

(Embodiment 2) As in Embodiment 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, as in Example 1, the inner surface of the hollow outer insulator 1a consists 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 different. After drying by using a coater on a sheet-shaped polyimide having a shape for forming a predetermined inner surface on which a conductor 2 can be formed so that each turn part has a plurality of turns Create a ferrite green sheet with a thickness of 0.6 mm,
The outer insulator 1a was formed.

Next, as in Example 1, the conductor 2 was formed on the inner surface of the outer insulator 1a. Further, as shown in FIGS. 4 to 10, the end face layer 4, the inner insulator 1b, the end face layer 3, the extraction electrode 5, the end face electrodes 7, 8 and the like are formed by the same method as in Example 1, and the temperature is set to 900 ° C. Firing was performed under the condition of holding 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, 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. Further, this method is more advantageous in terms of man-hours because the outer insulator 1a is formed in one step than the method shown in the first embodiment.

[0068]

As is apparent from the above description, the coil component of the present invention is not a laminated structure and thus is excellent in productivity, and moreover, it is a virtual conical or pyramidal stepped surface or the inside of an insulator. Since the conductor is located on the existing stepped surface, the height can be suppressed to a low level, and the stray capacitance between the turn portions of the conductor hardly occurs, and the electrical characteristics can be excellent. It is of great industrial value.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically 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 of an outer insulator showing a method for manufacturing a coil component according to the present invention.

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

FIG. 6 is a cross-sectional view of the completed conductor.

FIG. 7 is a sectional view showing a state where one end surface layer is formed.

FIG. 8 is a sectional view showing a state in which an inner insulator is formed.

FIG. 9 is a sectional view showing a state in which the other end surface layer is formed.

FIG. 10 is a cross-sectional view showing a state where an end face electrode is formed.

FIG. 11 is a schematic perspective view showing a conventional coil component.

FIG. 12 is an exploded perspective view of the same.

[Explanation of symbols]

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

Claims (4)

[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 and is in the same plane. Each turn part located is a coil component composed of a conductor consisting of multiple turns. 2. A non-magnetic material is provided between conductors of a plurality of turns of each turn portion located in the same plane.
Described coil parts. 3. One or both of 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. And the inner surface of a hollow insulator or the surface of a cone-shaped or pyramid-shaped insulator, 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. And a step of forming a conductor so that each turn portion located on the same plane is composed of a plurality of turns. 4. One or both of a step of forming a hollow body-shaped insulator having a conical or pyramidal hollow portion provided in the center and a step of forming a conical or pyramidal insulator. And the inner surface of a hollow insulator or the surface of a cone-shaped or pyramid-shaped insulator, 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. Located in the same plane, and each of the turns has a plurality of turns and a conductor is formed, and at least one of the upper and lower end faces of the hollow insulator or the conical or pyramidal insulator. And a step of forming an end surface layer on the coil.