JPH0451503A - Laminated transformer - Google Patents

Abstract

PURPOSE:To obtain a high quality laminated transformer having adequate function as an electronic component under severe environments by integral sintering of at least two conductors, through a non-magnetic insulator, enclosed in a magnetic substance and in addition by providing with film sheet form terminals to be connected to conductors on the magnetic surface corners. CONSTITUTION:Conductor 43 is fitted on a lower insulating magnetic sheet 41 with metal paste having a high melting point such as silver paste or silver alloy paste. This is further fitted with a non-magnetic insulator 45 and then with a conductor 44 in that order. An upper insulating magnetic sheet 42 is finally fitted to finish its assembling and laminated body having a closed magnetic path is formed by enclosing all of the substances mentioned above, except for the corner of the conductors 43 and 44. The whole body is sintered and then film sheet form electrode terminals 66A, 66B, 67A and 67B are provided, with printing or plating, on the conductor corners. The non-magnetic insulator 45 is composed of non-magnetic zinc ferrites.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to surface-mounted electronic components used in electronic circuits.
In particular, the present invention relates to a multilayer transformer used in high frequency circuits and mounted on one surface.

[Prior Art] Conventionally, in a laminated transformer as a surface-mounted electronic component, at least two linear or meandering conductors are surrounded by an insulating magnetic material and integrally sintered, as shown in FIG. In addition, film-shaped electrode terminals connected to the conductors were provided on the end faces of the magnetic body.

Note that the insulating magnetic material herein generally refers to a material that exhibits 1 ferromagnetic properties, as typified by NiZn ferrite, etc.
It is possible to sufficiently secure a resistivity of 105Ω or more.

[Problems to be Solved by the Invention] However, the structure of the conductor constituting the conventional multilayer transformer described above is such that its conductor surface is adjacent to the magnetic material surrounding the conductor.

Because they are used in harsh environments with high temperatures and humidity, short circuits may occur between the conductors due to the ingress of moisture, and the direct current resistance of the conductors themselves may increase due to migration or corrosion. There may be a disconnection.

Therefore, there was a drawback that the function as a laminated transformer was stopped.

Furthermore, in terms of characteristics, in the conventional laminated transformer, since the conductors are made of a magnetic material, there is a problem in that the magnetic coupling between the conductors is reduced.

By the way, the technical problem of the present invention is to provide a high-performance multilayer transformer that fully satisfies the function as an electronic part even when used in a harsh environment in view of the above-mentioned drawbacks, and has very advantageous magnetic coupling. That's true.

[Means for Solving the Problems] According to the present invention, there is provided a laminate body including a plurality of conductors spaced apart from each other and facing each other and a non-magnetic insulator interposed between the plurality of conductors; A laminated transformer is obtained, comprising an insulating magnetic material covering a main body, and a plurality of electrode terminals provided on the outer surface of the insulating magnetic material and electrically connected to each of the plurality of conductors. It was done.

Further, according to the present invention, there is provided a laminate body including a plurality of conductors facing each other and separated from each other and a non-magnetic insulator including the plurality of conductors, and an insulating magnetic material covering the laminate body. and a plurality of electrode terminals provided on the outer surface of the insulating magnetic material and electrically connected to each of the plurality of conductors.

Furthermore, according to the present invention, there is obtained the laminated transformer, wherein the nonmagnetic insulator includes zinc-based nonmagnetic ferrite.

That is, according to the present invention, in the first claim, at least two
The above-mentioned linear or meandering conductors are each surrounded by a magnetic material through a non-magnetic insulator, and are sintered together, and film-like electrode terminals are provided on the end faces of the magnetic material to connect with the conductors, respectively. This structure makes it possible to form a laminated transformer exhibiting extremely high magnetic coupling characteristics while ensuring sufficient dielectric strength between the conductors.

Further, in the second claim, the linear or meandering conductor is surrounded by the non-magnetic insulator, further surrounded by the magnetic body, and is sintered integrally with the magnetic body. By providing film-like electrode terminals connected to the conductors on the end faces of the body, even when used in harsh environments, it can sufficiently prevent moisture from entering and prevent short circuits between the conductors. Alternatively, it is possible to form a laminated transformer in which magnetic coupling is very advantageous in terms of characteristics while preventing increases in direct current resistance and disconnection of the conductor itself due to migration, corrosion, etc.

Incidentally, in general, a non-magnetic insulator is one that exhibits ferromagnetic characteristics, as typified by dielectric materials and the like.

It refers to a material that can sufficiently ensure a resistivity of 105Ωσ or more.

Furthermore, in the third TFT requirement, since the above-mentioned non-magnetic insulator is made of zinc-based non-magnetic ferrite, it can exhibit almost the same thermal behavior as the magnetic material,
It has become possible to form a stable and highly reliable multilayer transformer by integrally sintering different materials.

[Example] Next, an example of a laminated transformer according to the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of a first embodiment of a laminated transformer according to the present invention. For simplicity, the configuration is shown for one piece instead of a connected one, and a part of the conductor is shown with emphasis. There is.

In Fig. 1, each of the conductors 23 and 24 is configured to be surrounded by a non-magnetic insulator 25 and a magnetic material 21, thereby ensuring sufficient dielectric strength between the conductors while maintaining magnetic properties. It is possible to form a laminated transformer that exhibits extremely high coupling characteristics.

FIG. 2 shows a second embodiment of a laminated transformer according to the present invention.

For simplification, the configuration diagram is for one conductor rather than a connected one, and a portion of the conductor is shown with emphasis.

In Fig. 2, the conductors 33 and 34 are surrounded by a non-magnetic insulator 35, and the non-magnetic material is surrounded by a magnetic material 31, so that even if the conductor is used in a harsh environment, moisture will not be removed. Magnetic coupling is very advantageous in terms of characteristics, while sufficiently preventing the intrusion of the conductors, preventing short circuits between the conductors, or increasing the direct current resistance of the conductors themselves due to migration or corrosion, and preventing disconnection. It is possible to form a laminated transformer.

3 to 5 explain the configuration of FIG. 2 in more detail.

In FIG. 3, a conductor 43 is coated with Ag or Ag alloy paste on the lower magnetic sheet 41 of the upper and lower insulating magnetic sheets 41 and 42, which are produced by mixing ferrite magnetic powder and a suitable binding resin in a raw state. It is formed by printing or coating using a high melting point metal paste such as, and then on top of that, a 45 non-magnetic insulator is first formed, then a 44 conductor is formed using the same method, and finally an upper magnetic body is formed. The sheet 42 is used to cover the conductors 43 and 44 except for their ends to form a closed magnetic circuit laminate as shown in FIG.

Next, after the laminate is integrally sintered at an appropriate temperature, film-shaped electrode terminals 66A, 66B, and 67A are connected to the end surfaces of the conductor, respectively.

67B is provided by baking or plating as shown in FIG. As a result, as shown in FIG.

An equivalent model suitable for surface mounting in electronic circuits that can handle high frequencies and bands has been constructed in a simple and high-performance manner.

Furthermore, in the present invention, by using the non-magnetic insulator between the conductors or around the conductor, even when used in a harsh environment, the function as an electronic part is fully satisfied and magnetic coupling is achieved. It is possible to construct a highly advantageous high-performance laminated transformer, eliminating the drawbacks of conventional technology.

It can be said that the industrial benefits are extremely large in that it provides a surface-mount laminated transformer that can improve industrial economic efficiency and support high frequency bands.

Finally, in the configuration of the present invention, the magnetic material.

The conductor and the non-magnetic insulator are formed by a printing method or a coating method.

Dr.Frede method, extrusion molding method, injection molding method, etc.
I would like to add a note here just to be sure that no matter what manufacturing method is used to form the structure, there is no change in the effect for the purpose of this structure.

An isolated perspective view, FIGS. 4 and 5 are perspective views showing the attachment of electrode terminals in an embodiment according to the present invention, FIG. 6 is a conceptual diagram showing an equivalent model, and FIG. 7 is a sectional view of a conventional laminated transformer. It is.

21... Insulating magnetic material, 23.24... Conductor, 25
...Nonmagnetic insulator, 66A, B, 67A, B... Electrode terminal.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of the first and second embodiments of the present invention, and FIG. 3 shows the third factor of the first embodiment of the present invention. Figure 6 Procedural amendment (method) % formula % Display of the case 1990 Patent Application No. 159840 Name of the invention Multilayer transformer 3, person making the amendment Relationship with the case

Claims (1)

[Scope of Claims] 1) A laminated part main body having a plurality of conductors facing each other and separated from each other and a non-magnetic insulator interposed between the plurality of conductors, and an insulating magnetic material covering the laminated part main body. and a plurality of electrode terminals provided on the outer surface of the insulating magnetic material and electrically connected to each of the plurality of conductors. 2) A laminate main body including a plurality of conductors spaced apart from each other and facing each other and a non-magnetic insulator containing the plurality of conductors. A multilayer transformer comprising: an insulating magnetic material covering the main body of the multilayer section; and a plurality of electrode ends provided on the outer surface of the insulating magnetic material and electrically connected to each of the plurality of conductors. . 3) The multilayer transformer according to claim 1 or 2, wherein the nonmagnetic insulator includes zinc-based nonmagnetic ferrite.