JP4742516B2 - Multilayer coil component and manufacturing method thereof - Google Patents

Description

  The present invention relates to a laminated coil component, and more particularly, to a laminated coil component including a plurality of coils such as a laminated common mode choke coil and a laminated transformer, and a method for manufacturing the same.

  Conventionally, as a common mode choke coil for preventing the passage of noise having the same phase, for example, the one described in Patent Document 1 is known. This laminated common mode choke coil has a structure in which a plurality of ferrite sheets on which coil conductors are formed are stacked to form a spiral coil, and two to three coils are laminated. And the characteristic of a common mode choke coil is acquired because the magnetic field of adjacent coils couple | bonds together.

  However, in the common mode choke coil of Patent Document 1, in order to increase the withstand voltage, it is necessary to increase the number of ferrite sheets inserted between adjacent coils to increase the distance between adjacent coils. There was a problem that the size was increased.

Patent Document 2 describes an array-type noise filter in which a bonding layer made of glass is disposed between coils built in a ferrite laminate to prevent characteristic deterioration due to magnetic interference between the coils. ing. However, in the noise filter of Patent Document 2, since the coils are magnetically completely separated by the glass layer having a small relative permeability, the coupling between the coils becomes extremely weak, and desired characteristics cannot be obtained. was there.
JP 2003-77727 A JP-A-7-37744

  SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated coil component having a structure that can increase the dielectric strength between coils without increasing the height dimension of the component, and that reduces the amount of coupling between the coils, and a method for manufacturing the same. There is.

In order to achieve the above object, a laminated coil component according to the present invention includes:
(A) a laminate formed by stacking a plurality of magnetic layers and a plurality of coil conductors;
(B) at least two or more helical coils configured by electrically connecting coil conductors;
(C) an external electrode provided on the side surface of the laminate and folded back to the surface in the lamination direction;
With
( D ) The spiral coils have substantially the same diameter, and the axes of the respective coil portions are arranged on substantially the same line, and are juxtaposed in the stacking direction of the magnetic layers,
(E) between two adjacent helical coils mutually adjacent coil conductors, and the glass insulating layer of substantially annular formed on the magnetic layer is disposed,
(F) in the stacking direction of the magnetic layer, between the surface and the outermost layer of the coil conductors of the stack, the glass insulating layer of substantially annular formed on the magnetic layer is disposed,
It is characterized by.

With the above configuration, since the substantially annular glass insulating layer formed on the magnetic layer is disposed between the adjacent coil conductors of two adjacent spiral coils, the withstand voltage between the spiral coils is reduced. Goes up. Furthermore, since the magnetic substance exists in the vicinity of the coil center axis and the coil outer peripheral portion of the adjacent coil conductors, there is little decrease in the degree of magnetic field coupling between the coils. Further, by disposing a substantially annular glass insulating layer formed on the magnetic layer between the surface of the laminate and the outermost coil conductor, dielectric breakdown between the external electrode and the coil conductor can be prevented. .

Moreover, the manufacturing method of the laminated coil component according to the present invention is as follows:
( G ) forming a coil conductor on the surface of the magnetic material sheet;
( H ) forming a substantially annular glass insulating layer on the surface of the magnetic sheet;
( I ) Stacking magnetic sheets, electrically connecting coil conductors, the diameters of the respective coil portions being substantially equal, the axes of the respective coil portions being disposed on substantially the same line, and the stacking of magnetic sheets Forming at least two or more spiral coils juxtaposed in the direction, disposing a substantially annular glass insulating layer between adjacent coil conductors of two adjacent spiral coils , and in the stacking direction, a step of disposing a glass insulating layer of substantially annular between the surface and the outermost layer of the coil conductors of the stack,
(J) forming the external electrode on the side surface of the laminate by folding it back to the surface in the lamination direction;
It is characterized by having.

According to the present invention, since the substantially annular glass insulating layer formed on the magnetic layer is disposed between adjacent coil conductors of two adjacent spiral coils, the height dimension of the component can be reduced. The withstand voltage between the spiral coils can be increased without increasing it. Furthermore, since the magnetic substance exists in the vicinity of the coil central axis and the coil outer peripheral portion of the adjacent coil conductors, there is little decrease in the magnetic field coupling between the coils, and characteristic deterioration of the laminated coil component can be reduced. .

  Embodiments of a laminated coil component and a manufacturing method thereof according to the present invention will be described below with reference to the accompanying drawings.

[First embodiment, FIGS. 1 to 3]
As shown in FIG. 1, the laminated transformer 1 includes a magnetic sheet 2 having coil conductors 3 to 11 provided on the surface, a magnetic sheet 2 having glass insulating layers 16 to 19 provided on the surface, and the like. Yes.

The magnetic sheet 2 is made of, for example, Ni—Zn ferrite or Ni—Zn—Cu ferrite, and is manufactured by the following method (coprecipitation method) in the first embodiment. SO ₄ obtained by mixing a predetermined type of metal nitrate was 150 to 250 ppm (S: 33 to 83 ppm), Cl was 50 to 150 ppm, Na was 70 to 100 ppm, and Ca was contained in the range of 50 to 100 ppm. After the coprecipitate was calcined at 650 ° C., 2 wt% Co ₃ O ₄ or 0.35 wt% Mn ₃ O ₄ was added to the coprecipitate. A vinyl acetate binder and a plasticizer were mixed with the pulverized coprecipitate, and this was formed into a sheet having a thickness of about 50 μm by a doctor blade method. Needless to say, the magnetic sheet 2 may be manufactured by a method other than the coprecipitation method.

  The coil conductors 3 to 11 are made of Ag, Pd, Cu, Ni, Au, Ag-Pd or the like, and are formed on the magnetic sheet 2 by a method such as printing, sputtering, vapor deposition, or photolithography.

  The glass insulating layers 16 to 19 are made of Si, Si—B, Si—Al, or Si—Zn glass paste and include at least one of Ca, Sr, Ba, and Mg. The glass insulating layers 16 to 19 are formed on the magnetic sheet 2 by a method such as screen printing. The glass insulating layers 16 to 19 have a pattern width equal to or greater than the conductor width of the coil conductors 3 to 11 and have an annular pattern having a shape substantially similar to that of the coil conductors 3 to 11.

  The coil conductors 3 to 5 are electrically connected in series via via holes 15 provided in the magnetic material sheet 2, respectively, and form a spiral coil 12 having an axis parallel to the stacking direction of the magnetic material sheets 2. . The coil conductors 6 to 8 are electrically connected in series via via holes 15 provided in the magnetic material sheet 2, respectively, and form a spiral coil 14 having an axis parallel to the stacking direction of the magnetic material sheets 2. . The coil conductors 9 to 11 are electrically connected in series via via holes 15 provided in the magnetic material sheet 2, respectively, and form a spiral coil 13 having an axis parallel to the stacking direction of the magnetic material sheets 2. . These coils 12 to 14 are stacked in the order of 12, 14, and 13 from the top in the stacking direction of the magnetic sheets 2.

  The lead portion of the coil conductor 3 is exposed on the right side of the back side of the sheet 2. The lead portion of the coil conductor 5 is exposed on the right side of the front side of the sheet 2. The lead portion of the coil conductor 6 is exposed at the center of the front side of the sheet 2. The lead portion of the coil conductor 8 is exposed at the center of the back side of the sheet 2. The lead portion of the coil conductor 9 is exposed on the left side of the front side of the sheet 2. The lead portion of the coil conductor 11 is exposed on the left side of the back side of the sheet 2.

  The magnetic sheets 2 are stacked, and further, the outer layer magnetic sheets 2 are disposed above and below, and then fired integrally. Thereby, the laminated body 20 shown in FIG. 2 is obtained. Input electrodes 21 a, 23 a, 22 a and output electrodes 21 b, 23 b, 22 b of coils 12, 14, 13 are provided on the back side and the front side of the laminate 20.

  As shown in FIG. 3, the input side lead portion of the coil 12 is electrically connected to the input electrode 21a, and the output side lead portion is electrically connected to the output electrode 21b. The input side lead portion of the coil 14 is electrically connected to the input electrode 23a, and the output side lead portion is electrically connected to the output electrode 23b. The input side lead portion of the coil 13 is electrically connected to the input electrode 22a, and the output side lead portion is electrically connected to the output electrode 22b.

  The thus obtained laminated transformer 1 incorporates spiral coils 12 to 14 having the same coil diameter and coil axes arranged on the same line. The spiral coils 12 to 14 are juxtaposed in the stacking direction of the stacked body 20, and the degree of magnetic coupling between the coils 12 to 14 is increased by aligning the axes of the coils 12 to 14.

  Then, an annular glass insulating layer 17 is disposed between the adjacent two coil coils 12 and 14 and the adjacent coil conductors 5 and 6, and the adjacent two spiral coils 13 and 14 are adjacent to each other. Since the annular glass insulating layer 18 is disposed between the coil conductors 8 and 9, even if the distances between the spiral coils 12 and 14 and 13 and 14 are reduced, the coil conductors 5 and 6 or Migration between 8 and 9 and a decrease in insulation resistance can be prevented, and the withstand voltage can be increased.

  Further, since the patterns of the glass insulating layers 17 and 18 have substantially the same annular shape as the patterns of the coil conductors 3 to 11, there are magnetic properties in the vicinity of the coil axes of the adjacent coil conductors 5 and 6, and 8 and 9, and the vicinity of the coil outer periphery. There is a body and there is little decrease in the degree of magnetic coupling between the coils 12 and 14 and between the coils 13 and 14. As a result, predetermined electrical characteristics can be obtained, and a small-sized and highly reliable laminated transformer 1 can be obtained.

  Further, annular glass insulating layers 16 and 19 are disposed between the upper surface of the multilayer body 20 and the uppermost coil conductor 3 and between the lower surface of the multilayer body 20 and the lowermost coil conductor 11, respectively. Thus, migration between the external electrodes 21a to 23b and the coil conductors 3 and 11 and a decrease in insulation resistance can be prevented, and insulation breakdown can be prevented.

  In addition, the helical coil 14 does not necessarily need to be arrange | positioned in the center part of the lamination direction, and may be arrange | positioned at the upper part or the lower part. Further, the coil diameters of the spiral coils 12, 13, and 14 may not be the same. Furthermore, the glass insulating layers 16 to 19 do not have to be a complete annular pattern, and may be an intermittent substantially annular pattern cut in the middle.

[Second Embodiment, FIGS. 4 to 6]
As shown in FIG. 4, the laminated transformer 31 is composed of a magnetic sheet 32 having coil conductors 33 to 38 provided on the surface thereof, annular glass insulating layers 46 to 48, and the like. The coil conductors 33 to 35 are electrically connected in series via via holes 45 provided in the magnetic material sheet 32, respectively, and form a spiral coil 42 having an axis parallel to the stacking direction of the magnetic material sheets 32. . The coil conductors 36 to 38 are electrically connected in series via via holes 45 provided in the magnetic material sheet 32, respectively, and form a spiral coil 43 having an axis parallel to the stacking direction of the magnetic material sheets 32. .

  The lead portion of the coil conductor 33 is exposed on the left side of the back side of the sheet 32. The lead portion of the coil conductor 35 is exposed on the left side of the front side of the sheet 32. The lead portion of the coil conductor 36 is exposed on the right side of the front side of the sheet 32. The lead portion of the coil conductor 38 is exposed on the right side of the back side of the sheet 32.

  The glass insulating layers 46 to 48 are formed on the magnetic sheet 32 by a method such as screen printing. The glass insulating layers 46 to 48 have a pattern width equal to or greater than the conductor width of the coil conductors 33 to 38, and have an annular pattern that is substantially the same shape as the coil conductors 33 to 38.

  The magnetic sheets 32 are stacked, and further, the outer layer magnetic sheets 32 are arranged on the upper and lower sides, and then integrally fired. Thereby, the laminated body 50 shown in FIG. 5 is obtained. Input electrodes 51a and 52a and output electrodes 51b and 52b of coils 42 and 43 are provided on the back side and the front side surface of the laminated body 50, respectively.

  As shown in FIG. 6, the input side lead portion of the coil 42 is electrically connected to the input electrode 51a, and the output side lead portion is electrically connected to the output electrode 51b. The input side lead portion of the coil 43 is electrically connected to the input electrode 52a, and the output side lead portion is electrically connected to the output electrode 52b.

  The laminated transformer 31 obtained in this way incorporates helical coils 42 and 43 having the same coil diameter and coil axes arranged on the same line. The spiral coils 42 and 43 are juxtaposed in the stacking direction of the stacked body 50, and the degree of magnetic coupling between the coils 42 and 43 is increased by aligning the axes of the coils 42 and 43.

  Since the annular glass insulating layer 47 is disposed between the adjacent coil conductors 35 and 36 between the two adjacent spiral coils 42 and 43, the distance between the spiral coils 42 and 43 is reduced. In addition, migration between the coil conductors 35 and 36 and a decrease in insulation resistance can be prevented, and the insulation breakdown voltage can be increased.

  Further, since the pattern of the glass insulating layer 47 is substantially the same ring shape as the patterns of the coil conductors 33 to 38, there is a magnetic substance near the coil axis and the coil outer periphery of the adjacent coil conductors 35 and 36. There is little decrease in the magnetic field coupling between 42 and 43. As a result, predetermined electrical characteristics can be obtained, and a small and highly reliable laminated transformer 31 can be obtained.

  Further, annular glass insulating layers 46 and 48 are disposed between the upper surface of the multilayer body 50 and the uppermost coil conductor 33 and between the lower surface of the multilayer body 50 and the lowermost coil conductor 38, respectively. Thus, migration between the external electrodes 51a to 52b and the coil conductors 33 and 38 and a decrease in insulation resistance can be prevented, and insulation breakdown can be prevented.

[Other embodiments]
In addition, this invention is not limited to the said Example, It can change variously within the range of the summary. For example, an annular glass insulating layer provided between the upper surface of the laminate and the uppermost coil conductor and between the lower surface of the laminate and the lowermost coil conductor is not necessarily required. May be omitted.

  Further, in the above embodiment, the magnetic sheets on which the coil conductor and the glass insulating layer are formed are stacked and then fired integrally. However, the present invention is not necessarily limited thereto. A magnetic sheet that has been fired in advance may be used. Moreover, you may manufacture a laminated coil component with the manufacturing method demonstrated below. After forming a magnetic layer with a paste-like magnetic material by a method such as printing, apply a paste-like conductive material or glass insulating material to the surface of the magnetic layer to form a coil conductor or glass insulating layer To do. Next, a paste-like magnetic material is applied from above to form a magnetic layer. Similarly, a coil component having a laminated structure can be obtained by sequentially overcoating.

1 is an exploded perspective view showing the configuration of a first embodiment of a laminated coil component according to the present invention. FIG. 2 is an external perspective view of the multilayer coil component shown in FIG. 1. FIG. 3 is a schematic cross-sectional view of the multilayer coil component shown in FIG. 2. The disassembled perspective view which shows the structure of 2nd Example of the laminated coil component which concerns on this invention. FIG. 5 is an external perspective view of the multilayer coil component shown in FIG. 4. FIG. 6 is a schematic cross-sectional view of the laminated coil component shown in FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,31 ... Laminated transformer 2,32 ... Magnetic material sheet 3-11, 33-38 ... Coil conductor 12, 13, 14, 42, 43 ... Spiral coil 16-19, 46-48 ... Glass insulation layer 20, 50 ... Laminated body

Claims (2)

A laminate formed by stacking a plurality of magnetic layers and a plurality of coil conductors;
At least two or more helical coils configured by electrically connecting the coil conductors;
An external electrode provided on a side surface of the laminate and folded back to the surface in the lamination direction;
With
The spiral coils have substantially the same diameter, and the axes of the coil portions are arranged on substantially the same line, and are juxtaposed in the stacking direction of the magnetic layers.
Between adjacent two of said helical coil mutual adjacent coil conductors, and the glass insulating layer of substantially annular formed on the magnetic layer is disposed,
In the stacking direction of the magnetic layers, a substantially annular glass insulating layer formed on the magnetic layer is disposed between the surface of the laminate and the outermost coil conductor.
A laminated coil component characterized by Forming a coil conductor on the surface of the magnetic sheet;
Forming a substantially annular glass insulating layer on the surface of the magnetic sheet;
The magnetic sheets are stacked, the coil conductors are electrically connected, the diameters of the coil portions are substantially equal, the axes of the coil portions are arranged on substantially the same line, and the magnetic sheets are stacked. Forming at least two or more spiral coils juxtaposed in a direction, and arranging a substantially annular glass insulating layer between adjacent coil conductors of two adjacent spiral coils, and the magnetic body In the stacking direction of the sheets, a step of disposing a substantially annular glass insulating layer between the surface of the laminate and the outermost coil conductor;
Forming the external electrode on the side surface of the laminate by folding it back to the surface in the lamination direction;
A method for manufacturing a laminated coil component, comprising:

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