JP2001267127A - Laminated inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated inductor which has no directivity and moreover, can obtain the high value of an inductance. SOLUTION: A laminated inductor is constituted into a structure that spiral conductive layers 7a to 12a are embedded in the plane in an element body 1 and moreover, the winding shaft of the element body 1 intersects electrodes 2 and 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer inductor used for electronic equipment such as communication equipment.
In particular, the present invention relates to a multilayer inductor that performs noise absorption, inductance value matching, and the like.

[0002]

2. Description of the Related Art FIG. 6 is an exploded perspective view showing a conventional inductance element.

In FIG. 6, reference numerals 101 to 104 denote sheets, and sheets 102 and 103 have spiral patterns 10.
5, 106 are provided, the sheets 101 to 104 are stacked, electrodes (not shown) are formed at both ends, and the electrodes and the patterns 105, 106 are joined.

[0004]

However, in the above configuration, since the spiral pattern is formed on one surface of the substrate, the surface on which the pattern is formed is positioned on the mounting surface side of a circuit board or the like. There is a direction in the mounting that the characteristic changes depending on whether the mounting is performed or the device is positioned on the opposite side, so that a problem may occur when the mounting is performed. In addition, in order to increase the inductance or the like, there is a problem that the number of times of spiraling of the pattern must be increased, which results in an increase in the outer shape of the pattern and the size of the component itself.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a multilayer inductor which can be downsized even if the number of turns is increased.

Another object is to provide a multilayer inductor in which characteristics do not vary depending on the mounting direction.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a coil portion embedded in an element body, and a pair of electrodes embedded in the element body and electrically connected to the coil portion. A laminated inductor in which a shaft and the electrode intersect,
The coil portion was formed of a spiral conductor pattern formed in a planar shape.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an element body, a coil part embedded in the element body, and a pair of a coil part embedded in the element body and electrically connected to the coil part. An electrode, wherein the winding axis of the coil portion and the electrode intersect with each other, wherein the coil portion is formed by a spiral conductor pattern formed in a planar shape, so that the mounting direction is improved. Sex can be eliminated.

According to a second aspect of the present invention, a high inductance value can be obtained by forming a coil portion by joining a plurality of spiral conductive patterns in the first aspect, so that a wide inductance value is realized. Can,
The product range can be expanded.

According to a third aspect of the present invention, in the first aspect, a spiral conductor pattern is formed on one main surface of the sheet, and the sheet is provided with a through hole having a conductor to be joined to the conductor pattern. The number of sheets is adjusted by preparing a plurality of the sheets, laminating the plurality of sheets so that the conductive patterns do not directly face each other, and electrically configuring the plurality of conductive patterns to form a coil unit. This makes it possible to easily adjust the inductance value.

According to a fourth aspect of the present invention, in the first aspect, a spiral first conductive pattern is formed on one main surface of the first sheet, and the first conductive pattern is formed on the first sheet. A first sheet body provided with a through-hole having a conductor to be joined to the second sheet, and a second conductor pattern connecting a substantially central portion and an end portion on one main surface of the second sheet; A coil portion is formed by alternately stacking a second sheet body having a through hole having a conductor to be joined to the second conductor pattern on a sheet and the second sheet of the first sheet. Thus, since only one kind of spiral sheet needs to be prepared, workability is improved and productivity is improved.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 is a perspective view showing a laminated inductor according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an element body, in which a coil portion (described later) is embedded. Electrodes 2 and 3 are provided at both ends of the element body 1, respectively. The electrodes 2 and 3 are provided on the end surfaces 1a and 1b and on a part of the side surface 1c, respectively.

It is advantageous for miniaturization, element strength, and the like to satisfy the following conditions in which the length L1, height L2, and width L3 of the element body 1 are set.

0.5 mm ≦ L 1 ≦ 1.7 mm 0.2 mm ≦ L 2 ≦ 0.9 mm 0.2 mm ≦ L 3 ≦ 0.9 mm By defining the size of the element body 1 as described above,
Even when the elements are mounted on a circuit board or the like, the mounting area on the circuit board can be reduced, and the size of the circuit board and the size and thickness of an electronic device on which the circuit board is mounted can be reduced.

Further, by defining the size as described above, the number of turns of the coil portion can be secured to some extent, and the inductance value and the like can be matched to the characteristics of the circuit.

A feature of the multilayer inductor element configured as described above is that the axis of the coil portion embedded in the element body 1 intersects the end faces 1a and 1b of the element body 1 (particularly preferably, the winding shaft). Z and the end faces 1a and 1b intersect substantially perpendicularly). With such a configuration, even if any one of the four side surfaces 1c is brought into contact with or opposed to the circuit board, the change in the characteristics of the multilayer inductor becomes extremely small, and the directionality of the multilayer inductor can be eliminated. The performance is improved.

In this embodiment, since the element body 1 is formed in a prismatic shape and L2 = L3, the mountability is further improved. May be a prism having a regular polygonal cross section.

The corners of the element body (side surface 1c and side surface 1c)
, Etc., or where the side surfaces intersect with the end faces 1a, 1b)
By performing chamfering, chipping and cracking of the element body 1 can be prevented. The specific degree of chamfering is preferably 0.03 mm or more. If the chamfering is smaller than 0.03 mm, burrs and the like are likely to occur at corners, and chipping of the element body 1 and the like occur.

Further, it is preferable that the protruding length L4 of the portion protruding to the side surface 1c of each of the electrodes 2 and 3 is L4 ÷ L1 ≦ 0.25 based on the length L1 of the element body 1. When L4 ÷ L1 is larger than 0.25, when the element body 1 is mounted on a circuit board, a bonding material such as solder largely protrudes to the side of the element body 1, and the mounting density can be improved. Can not. Further, when L4 ÷ L1 is larger than 0.25, the interval between the electrodes 2 and 3 becomes narrow, and the possibility that the electrodes 2 and 3 are short-circuited when mounted on a circuit board or the like increases. Note that L4 ÷ L1 = 0 means that the end faces 1a,
This shows that only electrodes 1b are provided with electrodes 2 and 3, respectively.

Next, the coil section will be described.

FIG. 2 is a sectional view showing a laminated inductor according to an embodiment of the present invention.

In FIG. 2, reference numeral 4 denotes a coil portion, and the coil portion 4 is buried in the element body 1. As described above, the winding axis Z of the coil portion 4 and the end faces 1a and 1b (or the electrodes 2 and 3) of the element body 1 are configured to intersect (particularly preferably to intersect substantially vertically). Further, lead portions 5 and 6 are electrically connected to both ends of the coil portion 4, respectively, and the lead portions 5 and 6 are respectively connected to the electrodes 2 and 3. The coil unit 4 is configured by laminating sheets as shown in FIG.
In FIG. 3, reference numerals 7 to 12 denote laminated sheets, and the laminated sheets 7 to 12 are basically made of a dielectric material, a magnetic material,
Conductive layers 7a to 12a are formed by patterning a conductive material such as a conductive metal such as copper, silver, and gold, or a conductive alloy on a sheet made of an insulating material or the like. The conductor layers 7a to 12a are formed on one main surface of the sheets 7 to 12, and are formed in a spiral shape (flat spiral pattern). In the present embodiment, the outer shape is a rectangular spiral, but the outer shape may be a circular shape. When laminating the sheets 7 to 12, it is preferable that the conductor layers 7a to 12a do not directly contact.

Further, through holes 7b to 12b and bonding patterns 7c to 12c are provided at the ends of the conductor layers 7a to 12a, and a conductor (not shown) is provided inside the through holes 7b to 12b. Have been.

Specifically, the conductor layer 7a of the sheet 7 is electrically connected to the bonding pattern 8c provided on the conductor layer 8a of the sheet 8 through the through hole 7b.

Similarly, the conductor layer 8a is connected to the bonding pattern 9 provided on the conductor layer 9a of the sheet 9 through the through hole 8b.
c, and the conductor layers are electrically connected to each other in the same configuration.

Reference numerals 13 and 14 denote sheets on which the drawing portions 5 and 6 are formed, and the length of the drawing portions 5 and 6 is determined by the thickness of the sheets 13 and 14. Specifically, through holes are provided in the sheets 13 and 14, and lead portions 5 and 6 are formed in the through holes. Further, the drawer 5 is joined to the joining pattern 7c,
The drawer 6 is electrically connected to the through hole 12b.

Then, the coil portion 4 is connected to the
And the electrodes 2 and 3 are electrically joined.

The thickness of each conductor layer is 5 μm to 2 μm.
When the thickness is 5 μm, good conductivity is exhibited, and it is suitable for miniaturization. Further, the thickness of the sheets 7 to 14 is preferably set to a thickness of 20 μm to 200 μm.

Hereinafter, another embodiment will be described.

FIG. 4 differs from FIG. 3 in the structure of the sheets 13 and 14. Other points are the same as those in FIG.

The sheet 13 is not provided with a through hole, and has a cross-shaped conductor layer 13a on one main surface. The sheet 14 has a through hole, and a conductor portion is provided in the through hole. Further sheet 12
A cross-shaped conductor layer 13a is provided on the side opposite to the side on which is provided.

The conductor layer 13 is in electrical contact with the coil portion 4 through the through hole 7c, and the conductor layer 14a is
4, is connected to the conductor layer 12 a through a through hole provided in the coil 4, and is electrically connected to the coil portion 4.

Reference numerals 15 and 16 denote sheets provided outside the sheets 13 and 14, and the sheets 15 and 16 are provided for protection of elements and protection of conductor patterns.

In the above configuration, preferably, the electrodes 2 and 3 are formed only on the side surface of the element body 1 (the electrodes 2 and 3 are not provided on the end face of the element body 1), so that a so-called filletless Since the structure can be adopted, high-density mounting and deterioration of the Q value can be prevented.

In this embodiment, the conductor layers 13a,
Although 14a has a cross shape, any conductor layer structure that is exposed on the side surface of the element body 1 may be used.

Next, still another embodiment will be described.

As shown in FIG. 5, the point different from that shown in FIG. 3 is that the spiral conductor pattern has the same configuration. Other structures are the same as those shown in FIG.

As shown in FIG. 5, spiral conductive layers 17a to 19a are provided on the sheets 17 to 19, and the sheets 20 to 22 connect the center portions of the sheets 20 to 22 with the ends. Conductive layers 20a to 22a are provided.

With the above-described configuration, only one kind of sheet having a spiral pattern is required, workability is improved, and productivity is improved.

Next, the electrodes 2 and 3 will be described.

The specific structure of the electrodes 2 and 3 is, for example, a structure in which a paste of a conductive material such as silver is baked, or a corrosion-resistant film such as nickel is provided on the baked conductive portion. Alternatively, a bonding film made of solder, lead-free solder, or the like may be provided on the corrosion-resistant film from above the conductive portion.

The electrodes 2 and 3 include: only a conductive portion formed by baking a conductive material or the like; providing a bonding film on the conductive portion; providing a corrosion-resistant film on the conductive portion; and further forming a bonding film thereon. There is a specific structure such as providing.

As described above, the laminated inductor of the present embodiment can extremely reduce the directionality such as a change in characteristics on the mounting surface, and can be suitably used for bulk mounting, etc. By laminating the conductor layers in a shape, a high inductance value can be realized while being a very small element, and an assortment of elements having a wide range of inductance values can be provided.

[0046]

According to the present invention, there is provided a coil part buried in an element body, and a pair of electrodes buried in the element body and electrically connected to the coil part. Are crossed, and the coil portion is formed of a spiral conductor pattern formed in a planar shape, so that the directionality at the time of mounting can be eliminated.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a laminated inductor according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a multilayer inductor according to an embodiment of the present invention.

FIG. 3 is an exploded perspective view showing the multilayer inductor according to one embodiment of the present invention.

FIG. 4 is an exploded perspective view showing a laminated inductor according to another embodiment of the present invention.

FIG. 5 is an exploded perspective view showing a laminated inductor according to another embodiment of the present invention.

FIG. 6 is an exploded perspective view showing a conventional inductance element.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Element body 1a, 1b End surface 1c Side surface 2, 3 Electrode 4 Coil part 5, 6 Lead-out part 7, 8, 9, 10, 11, 12, 13, 14, 17, 1
8, 19, 20, 21, 22 sheets 7a, 8a, 9a, 10a, 11a, 12a, 13a,
14a, 17a, 18a, 19a, 20a, 21a, 2
2a conductive layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Mika Ikeda 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Terms (reference) 5E070 AA01 AB04 BA12 CB02 CB13

Claims (4)

[Claims] An element body, a coil part embedded in the element body, and a pair of electrodes embedded in the element body and electrically connected to the coil part; A laminated inductor in which a shaft and the electrode intersect,
A coil inductor comprising a spiral conductor pattern formed in a planar shape. 2. The multilayer inductor according to claim 1, wherein a coil portion is formed by joining a plurality of spiral conductive patterns. 3. A spiral conductive pattern is formed on one main surface of the sheet, a through hole having a conductor to be joined to the conductive pattern is provided in the sheet, and a plurality of the sheets are prepared.
The multilayer inductor according to claim 1, wherein the plurality of sheets are stacked so that the conductive patterns do not directly face each other, and the plurality of conductive patterns are electrically joined to form a coil portion. 4. A spiral first surface on one main surface of a first sheet.
And forming a first conductive pattern on the first sheet.
A first sheet body provided with a through-hole having a conductor to be joined to the conductor pattern, and a second conductor pattern connecting a substantially central portion and an end portion on one main surface of the second sheet; Second
A second sheet body provided with a through hole having a conductor to be joined to the second conductor pattern on the first sheet, and the first sheet and the second sheet were alternately laminated to form a coil portion. The multilayer inductor according to claim 1, wherein: