JPH09148133A - Laminated inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the productivity by forming a pair of coil conductors having symmetric property in a step of making even in the directions of a laminated inductor. SOLUTION: Within a laminated inductor 11, an inner conductor 12 is formed in coil form further forming respective ends of this inner conductor 12 to make the first pair of leading-out conductors 13, 14, furthermore, within the laminated inductor 11 wherein these leading-out conductors 13, 14 are mutually extending in the opposite directions, the second leading-out conductors 22 and the second pair of leading-out conductors 23, 24 are likewise formed to make the central axial lines 1, 2 of this pair of coils in parallel with each other. Furthermore, the laminated inductor is formed so that this leading-out conductors extending in the opposite directions may be made in parallel with one another and these two pairs of inner conductors 12, 22 and these two pairs of leading-out conductors may have the symmetric property to the axial lines in parallel with said coil type central axial lines.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductor utilizing an electromagnetic induction effect, and more particularly to a laminated inductor in which coil conductors are laminated. The present invention more specifically relates to a chip-type multilayer inductor, and more specifically, the present invention relates to a structure in consideration of the arrangement attitude of the multilayer chip inductor.

[0002]

2. Description of the Related Art In recent years, a very small laminated inductor, in which a coil-shaped conductor is formed by laminating, a so-called laminated chip inductor is widely known. This multilayer chip inductor has, for example, a chip size of 2.0 ×
It is 1.25 (mm) and the number of turns of the coil is 5 turns.

Among the types of multilayer chip inductors, those having a low inductance value, which are mainly used in high frequency circuits, use a material having a magnetic permeability close to 1 as the material of the chip body. Therefore, in the low-inductance multilayer chip inductor, as shown in FIG. 5B, the magnetic flux 53 generated by the coil conductor 52 inside the chip main body 5 is generated.
1 has an open magnetic circuit type structure that leaks out from the outside.

To add a description here, the inductor used in the high frequency circuit has a small inductance value. Therefore, the number of windings of the coil conductor 52 is reduced, and the chip body 51 is made of a non-magnetic material instead of a magnetic material to obtain a smaller inductance value. Therefore, the chip body 5
Since a material having a low magnetic permeability is used for No. 1, the magnetic flux 53 leaks to the outside of the chip body 51 as shown in FIG.

Incidentally, what is shown in FIG.
It is a closed magnetic circuit type multilayer chip inductor and has a structure in which a magnetic flux 55 generated by an internal coil conductor 54 does not leak out of the chip body 56.

As described above, in the open magnetic circuit type multilayer chip inductor, since the magnetic flux 53 leaks out of the chip body 51, the influence of an object around the chip body 51 is reduced.
You will inevitably receive it.

From this, for example, as shown in FIG. 6, when the chip main body 51 is mounted on a circuit board, the winding direction of the coil conductor 52 inside the circuit board 61 is horizontal or vertical. The influence of the circuit board 61 on the magnetic flux 53 differs depending on whether or not. In addition, if there are other parts 62 around, the magnetic flux 53 is further affected differently.

That is, depending on the arrangement posture of the chip body 51, the influence of the circuit board 61 or other parts 62 around it differs with respect to the magnetic flux 53, and as a result, the influence of these magnetic fluxes 53 becomes different, and the chip body 51 becomes different. There was a problem that the predetermined inductance value of was changed.

Further, the coil conductor 52 inside the chip is
As shown in FIGS. 7A and 7B, the conductor 71 at the beginning of the winding and the conductor 72 at the end of the winding have asymmetry, so that the magnetic flux 53 is generated in the longitudinal direction or the width direction of the chip body 51. The leakage is asymmetrical, and as a result, due to the difference in the effects of the circuit board and other surrounding components,
Further, there is a problem that a difference occurs in the inductance value.

In order to solve the above-mentioned problems, in the conventional open magnetic circuit type multilayer chip inductor, as shown in FIG.
As shown in (A) of FIG. 7, a marker 82 is provided at a predetermined position of the laminated chip inductor 81 which is a product. More specifically, the lead conductor 7 at the beginning of winding the coil conductor 52.
In order to make 1 clear, one marker 82 indicating the winding start position of the coil conductor 52, the multilayer chip inductor 8
It was attached to the surface of 1.

In other words, when the multilayer chip inductor 81 is mounted on the circuit board, the influence of the magnetic flux leaking from the multilayer chip inductor and the influence on the circuit board or other peripheral parts is always constant. Marker 8
The above problems were solved by keeping 2 always in the same position.

External terminals 83 and 84 are formed on both outer sides of the laminated inductor 81, respectively. The external terminal 83 is connected to the lead conductor 71, and the external terminal 84
Is connected to the lead conductor 72.

[0013]

As described above, in the conventional open magnetic circuit type multilayer chip inductor, one marker is formed in order to define the arrangement posture at the time of mounting.

On the other hand, when measuring the electrical characteristics of the multilayer chip inductor itself, or when packaging the multilayer chip inductor for packaging, it is necessary to arrange the multilayer chip inductors in a certain direction. In other words, when examining the electrical characteristics of the multilayer chip inductor itself, a step of aligning the above markers in a certain direction is required, and in order to align the above markers in a certain direction and tape them, A process of aligning the directions in a uniform manner was necessary.

Conventionally, the direction regulating step for aligning the direction of one marker in a fixed manner is a very troublesome step.
Even when automated, the number of chip parts processed per hour was small, and there was a problem that productivity was extremely low.

For example, as is apparent from FIG. 8B, even when the laminated chip inductor 81 has the same orientation direction, as shown by a to h depending on the position of the marker, there are eight types. There will be an arrangement posture of. Therefore, in the step of aligning the direction of one marker in a constant manner, it is necessary to align at least eight kinds of arrangement postures a, b, c, ...

Here, the process of aligning the markers in a fixed direction will be schematically described. In this case, generally, a device called a parts feeder (not shown) is used as a device for arranging the chip parts in a line. The parts feeder puts parts such as chip parts in a dish-shaped container and gives vibration to the dish-shaped container. The plate-shaped container has a path around which the parts can pass from the bottom of the plate-shaped container along the peripheral wall of the plate-shaped container. The road has a wall on the outer peripheral side but no wall on the inner side. When vibration is applied to the dish, the chip component moves and follows the path along the dish. At first, it starts moving in various postures, but since the road is narrow and there is no wall on one side, chip components in an unstable posture fall from the road and fall to the bottom of the dish-shaped container. Only chip components with a stable posture continue to progress.

The stable posture described here means that when the chip component is the multilayer chip inductor 81 shown in FIG.
Of the eight types shown in FIG. 8 (B), only the eight types of arrangement postures that move in the longitudinal direction will continue to the final stage. In the final stage, the marker is image-recognized by the CCD camera, and the inappropriate one is thrown off the road by the information from the CCD camera. The only objects that pass through here are those with the markers aligned in a certain direction.

As described above, the step of aligning the direction of one marker in a constant manner is a very laborious process,
Even when automated, the number of chip parts processed per hour was small, and there was a problem that productivity was extremely low.
The present invention was developed for the purpose of solving this problem.

[0020]

The laminated inductor of the present invention is an open magnetic circuit type laminated chip inductor in which a pair or a plurality of pairs of internal conductor coils are internally provided, and each pair of internal conductor coils is the center of the chip. A laminated inductor characterized by being arranged in line symmetry with the axis (1) as the axis of symmetry, and the most preferable representative one is that the inner conductor is formed in a coil shape by lamination and each of the inner conductors is formed. In a laminated inductor in which the ends are a pair of lead conductors and these lead conductors are connected to both external terminals, a second inner conductor and a second pair of lead conductors are formed in the same manner as described above. Then, the central axes of these two coil types are made parallel to each other, the lead conductors extending in opposite directions are made parallel to each other, and the lead conductors pass through the center of the chip. Respect yl shaped two central axes parallel to the axis line, the two inner conductor and the two pairs of lead conductors, characterized in that were formed with a symmetry.

In one embodiment, the laminated inductor of the present invention is characterized in that a marker is formed on the surface of the laminated inductor through which the axis passes.

In another aspect, the laminated inductor of the present invention is characterized in that two markers are formed, that is, one marker is formed on each of the upper and lower surfaces of the laminated inductor.

In one embodiment of the method for manufacturing a laminated inductor according to the present invention, a step of arranging a green sheet having the marker so that the marker is arranged outside the surface of the laminated inductor. It is characterized by having.

In another aspect of the method for manufacturing a laminated inductor of the present invention, there is provided a step of arranging a green sheet having the marker so that the marker is arranged inside a surface of the laminated inductor. Is characterized by.

Furthermore, in another aspect, the method for manufacturing a laminated inductor according to the present invention is characterized by including a step of forming the marker on a green sheet that disappears by firing.

[0026]

Thus, according to the invention, one or more pairs of, for example, two coil-shaped inner conductors are provided.
Since it will be arranged so as to have symmetry with respect to the axis parallel to the central axis of these coil shapes passing through the center of the chip, on the surface of the laminated inductor on this axis,
When one marker is formed, the arrangement attitude in the longitudinal direction of this laminated inductor is halved from eight types to four types, and as a result, the process of aligning the direction of the markers to a certain extent is significantly improved. As a result, the number of treatments per hour is greatly improved, and the productivity is extremely high.

Further, according to the present invention, in the case where two markers are formed on the opposite surfaces of the laminated inductor on the axis parallel to the central axis of the coil, a total of two markers,
The arrangement attitude of this laminated inductor in the longitudinal direction is 8
The number of types will be drastically reduced from two to two, and the process of aligning the orientations of the markers in a fixed manner will be significantly improved, and the number of treatments per time will be significantly increased.

[0028]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example with reference to the accompanying drawings, in which: FIG.

1A and 1B are drawings showing an embodiment of a laminated inductor according to the present invention. FIG. 1A is a perspective view of the laminated inductor, and FIG. 1B is a perspective view showing various arrangement postures of the laminated inductor. is there. 2A and 2B are views showing a second embodiment of the laminated inductor according to the present invention, respectively.
FIG. 3B is a perspective view of the multilayer inductor, and FIG. 6B is a perspective view showing an arrangement posture of the multilayer inductor. FIG. 3 is an explanatory view showing one embodiment of the laminated inductor manufacturing method according to the present invention, and FIG. 4 is an explanatory view showing a second embodiment of the laminated inductor manufacturing method according to the present invention.

FIG. 1A is a perspective view showing the whole laminated inductor 11 according to one embodiment of the present invention. As shown, the laminated inductor 11 is formed in a rectangular parallelepiped shape. Reference numeral 12 is a coil-shaped inner conductor.
Is formed near the center inside the laminated inductor 11. 13 and 14 are lead conductors, and lead conductor 1
3, 14 are connected to the respective ends of the inner conductor 12. In other words, the lead conductors 13 and 14 are the winding start and winding end of the coil-shaped inner conductor 12, and extend in opposite directions.

Reference numeral 22 is also a similar coil-shaped internal conductor, and this internal conductor 22 is also formed in the laminated inductor 11 near the center thereof. In other words, the coil-shaped inner conductor 22 is formed in the vicinity of the first coil-shaped inner conductor 12 described above. Reference numerals 23 and 24 denote lead conductors, and the lead conductors 23 and 24 are connected to respective ends of the internal conductor 22 and extend in opposite directions.

As a result, the first coil-shaped inner conductor 12
And the second coil-shaped inner conductor 22 are the inner conductor 12,
22 has a symmetry with respect to the vertical axis 1 passing through the center of the chip, which is parallel to the central axis of each coil shape, and is rotated by 180 ° around the axis 1 to form the coil 12. The coil 22 is replaced, but the state before rotation is the same.

External terminals 15 and 16 are formed outside both ends of the laminated inductor 11, respectively. The external terminals 15 are connected to the lead conductors 13 and 24, and the external terminal 16 is connected to the lead conductors 14 and 23. Has been done.

A marker 17 is formed on the outer upper portion of the laminated inductor 11. The marker 17 is, for example, for indicating the position of the pair of lead conductors 13 and 24. However, since the laminated inductor 11 has the above-mentioned symmetry with respect to the axis line 1, the other conductors of other pairs are provided. The positions of the lead conductors 14 and 23 will also be shown. In other words,
Since the two inner conductors 12 and 22 are formed in the laminated inductor 11 so as to have symmetry with respect to the axis line 1 as shown in the figure, the laminated inductor 11 is distinguished in the longitudinal direction, that is, There is no need to distinguish between the left and right directions.

As described above, when the laminated inductor has two internal conductors, the two internal conductors 12 and 22 have symmetry with respect to the axis 1, and as a result, the overall symmetry is maintained. It is possible to reduce the direction while keeping it.

That is, even if the position of the marker 17 is one, by utilizing the symmetry of the inner conductors 12 and 22, as shown in the arrangement postures a, b, c and d of FIG. 1 (B). In addition, the coiled inner conductors 12 and 22 have four types, two types of vertical or horizontal and two types of front or back, and the directionality can be reduced to four. Productivity can be increased.

FIG. 2A is a perspective view showing a second embodiment according to the present invention. Briefly, it is a laminated inductor 21 in which a marker 18 is formed on the outer lower portion of the laminated inductor of FIG.

In the second embodiment as described above, the two inner conductors 12 and 22 of the laminated inductor 21 seem to have no symmetry at first glance, but the inner conductors 12 and 22 are not symmetrical.
It can be seen that there is symmetry with respect to the second axis 2 that passes through the center point of the coil pattern. In consideration of this, if the positions of the markers 17 and 18 are set to two places which show the upper and lower sides of the first axis 1 of the inner conductors 12 and 22, two markers 17,
18 has symmetry with respect to the second axis 2, and as a result, it is possible to reduce the directionality while maintaining the overall symmetry of the laminated inductor 21.

That is, by utilizing the symmetry of the internal conductors 12 and 22 and the lead conductors 13, 14, 23 and 24, the markers 17 and 18 are provided at the upper and lower portions of the chip, respectively. As shown in the arrangement postures a and b, the coiled inner conductors 12 and 22 can be reduced to two types, that is, vertical or horizontal, in other words, the directionality can be reduced to two, and Productivity can be greatly increased.

The manufacturing process of the laminated inductor 11 described with reference to FIG. 1 will be described with reference to FIG. The chip size of the laminated inductor 11 is, for example,
It is 2.0 × 1.25 (mm), and the number of turns of the coil is 5 turns.

In FIG. 3, first, two unprinted green sheets 31 are placed on top of each other, then a green sheet 32 with lead conductors 14 and 24 is laminated on the green sheet 31, and an internal conductor is placed on the green sheet 32. A raw sheet 33 having a part of 12, 22 is laminated, and another raw sheet 34 having a part of the internal conductors 12, 22 is further laminated on the raw sheet 33, and as shown in the drawing, The sheets 33 and 34 are repeatedly laminated, the raw sheet 35 with the lead conductors 13 and 23 is laminated on the final raw sheet 34, and the unprinted raw sheet 36 is laminated on the raw sheet 35. The green sheets 37 on which the markers 17 are printed are stacked, and then pressure-bonded and fired to manufacture the multilayer inductor 11.

In the case of FIG. 3, for example, the marker 1
The thickness of the green sheet 37 printed with No. 7 and the green sheets 31 and 36 without printing is 200 μm, the other green sheets are 150 μm, and the number of laminated layers is 12.

FIG. 4 is an explanatory view showing another method for manufacturing a laminated inductor, but it goes without saying that it has manufacturing steps almost similar to those in FIG. In FIG. 4, first, the raw sheet 41 on which the markers 18 are printed is placed upside down, a raw sheet 42 without printing is laminated on the raw sheet 41, and then the raw sheet 42 with the lead conductors 14 and 24 is formed. The sheet 43 is laminated, and the inner conductor 1 is attached to the raw sheet 43.
A raw sheet 44 having a part of 2, 22 is laminated, and further,
Another raw sheet 45 having a part of the internal conductors 12 and 22 is laminated on the raw sheet 44, and as shown in the drawing,
The raw sheets 44 and 45 are repeatedly laminated, and the final raw sheet 45 is provided with the lead conductors 13 and 23.
6 is laminated, a raw sheet 47 without printing is laminated on the raw sheet 46, and finally, a raw sheet 48 on which the marker 17 is printed is laminated, and then, pressure bonding and baking are performed, and then, as shown in FIG. The laminated inductor 21 is manufactured.

[0044]

According to the present invention as described above, the number of arranging postures of the laminated conductor is reduced by half by adding a simple structure of forming two symmetrical coil conductors inside the laminated inductor. Can be reduced to a quarter, and as a result, the productivity of the process of arranging the laminated inductors in the same arrangement attitude can be improved.
It is possible to dramatically increase the production cost of the multilayer chip inductor.

[Brief description of the drawings]

FIG. 1 is a drawing showing an embodiment of a laminated inductor according to the present invention, (A) is a perspective view of the laminated inductor, and (B) is a perspective view showing various arrangement postures of the laminated inductor.

2A and 2B are views showing a second embodiment of the multilayer inductor according to the present invention, FIG. 2A is a perspective view of the multilayer inductor, and FIG.
FIG. 3 is a perspective view showing an arrangement posture of the above laminated inductor.

FIG. 3 is an explanatory view showing an example of a method for manufacturing a laminated inductor according to the present invention.

FIG. 4 is an explanatory view showing a second embodiment of the method for manufacturing a laminated inductor according to the present invention.

FIG. 5 is a schematic cross-sectional view for explaining the type of laminated inductor.

FIG. 6 is a schematic cross-sectional view for explaining a mounting example of a laminated inductor.

FIG. 7 is a schematic cross-sectional view for explaining a change in magnetic flux of a laminated inductor.

FIG. 8 is a view showing a conventional laminated inductor, (A).
FIG. 3 is a perspective view showing a conventional laminated inductor, and FIG. 6B is a perspective view showing various arrangement postures of the laminated inductor.

[Explanation of symbols]

 1, 2: axis line 11, 21: laminated inductor 12, 22: internal conductor 13, 14, 23, 24: lead conductor 15, 16: external terminal 17, 18: marker

Claims (4)

[Claims] 1. An open magnetic circuit type multilayer chip inductor having a pair or a plurality of pairs of internal conductor coils provided therein.
A multilayer inductor, wherein each pair of inner conductor coils are arranged in line symmetry with the central axis (1) of the chip as the axis of symmetry. 2. A laminated inductor in which an inner conductor is formed in a coil shape by lamination, and each end portion of the inner conductor forms a pair of lead conductors, and the lead conductors are connected to both external terminals, Further, a second inner conductor and a second pair of lead conductors are formed in the same manner as described above, and the respective central axis lines of these two coil shapes are made parallel to each other, and the lead conductors extending in opposite directions are mutually formed. The two internal conductors and the two pairs of lead conductors are formed so as to be parallel to each other and to the axis parallel to the two center axes of the coil shape and passing through the centers of the chips. Is a laminated inductor. 3. The laminated inductor according to claim 1, wherein a marker is formed on a surface of the laminated inductor through which the axis passes. 4. The multilayer inductor according to claim 3, wherein one of the markers is formed on each of two opposing surfaces of the multilayer inductor.