JPH02205308A - Impedance element and production device thereof - Google Patents

Abstract

PURPOSE:To form an impedance element economically by a method wherein an electrode terminal for external leading-out is formed to a cut edge surface while being connected to a conductor in a laminate in a green laminate in which the conductor is held between two magnetic substance layers, the layers are overlapped continuously, and the overlapped layers are cut in desired size and shaped. CONSTITUTION:One conductor 2 is laminated at the central section of a slightly thick magnetic substance layer 1 formed by extrusion molding magnetic paste through extrusion molding from conductor paste, in which a bonding resin and a solvent are mixed and kneaded with a high melting-point metal such as Ag or the powder of an alloy, while both ends are exposed to edges. A magnetic substance layer 1' is overlapped and laminated to the upper layer of the layer 1, and a green laminate 3 in which the end faces of the conductor 2 are exposed to both edges is shaped. The green laminate 3 is sintered integrally at a fixed temperature, and electrode terminals 4, 4', in which both edge surfaces of the green laminate 3 are covered with a conductive material while being connected to the conductor 2 exposed to both end faces, are shaped, thus forming an impedance element. Accordingly, laminating processes are decreased, and the economical impedance element is easily obtained.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to printed wiring boards formed by alternately laminating magnetic layers made of magnetic materials and conductors, etc. In order to prevent disturbances due to electromagnetic induction emitted or received from the outside, surface-mounted impedance elements are used that are attached to substrates such as printed wiring boards. Conventionally, in this type of impedance element, a magnetic sheet is formed by a printing method or a doctor blade method from a magnetic paste made by mixing ferrite or other ferromagnetic powder with a binding resin and a solvent and kneading the mixture. A raw laminate is formed by printing a conductor with both ends protruding from a portion of the magnetic layer formed by laminating a plurality of these magnetic sheets, and then laminating the magnetic layer thereon again. An impedance element is formed by integrally sintering the green laminate and providing electrode terminals connected to both ends of the conductor and having both edges covered with a conductive material. Therefore, the laminated magnetic layers form a closed magnetic path in response to the magnetic field generated by passing a current through the conductor, and the electrode terminals are directly attached to the substrate.

<Problems to be solved by the invention> However, in conventional impedance elements of this type, in order to increase the impedance value or DC superposition characteristics in a desired frequency band, a sufficient magnetic path must be secured.
The thickness of the magnetic layer is typically 1111Il, at least 0.5
About mm is necessary.

Therefore, in the case of a printing method using a magnetic paste, the number of printing and drying steps or the time required are very large, and impedance elements cannot be formed economically. Further, even when using the doctor blade method, the thickness of the magnetic material sheet is several microns, and it requires an enormous amount of lamination man-hours to laminate layers up to about 1 txx, making it impossible to form them economically.

Furthermore, even if a large number of conventional impedance elements are manufactured in a process, there is a drawback that the process from forming to cutting individual impedance elements from a magnetic sheet cannot be consistently achieved.

Means for Solving the Problems> The present invention solves the above drawbacks of the conventional method and creates a magnetic paste by mixing and kneading ferrite magnetic powder and high melting point metal such as Ag or alloy powder with a binding resin and a solvent. and produce conductor paste. Here, the conductive paste is extruded between two pieces of magnetic paste.
A conductor is sandwiched between two magnetic layers and stacked one on top of the other, and this is cut into desired dimensions to form a green laminate.The conductor is connected to the conductor in the carcass, and an electrode terminal for external extraction is formed on the cut edge. It is an impedance element provided with.

Furthermore, these raw laminates have two magnetic material extrusion mechanisms, upper and lower, in which magnetic paste is filled and a slightly thick magnetic layer is extruded by a magnetic head, and a conductor paste is filled in between and a conductor is extruded by a conductor head. Extrusion mechanism, extruded magnetic sheet and conductor action> The magnetic layer extruded from the upper and lower magnetic extrusion mechanisms and the conductor extruded from the conductor extrusion mechanism between them form a continuous band-like body. An impedance element is obtained by cutting, integrally sintering, and providing electrode terminals.

<Example> Examples of the impedance element of the present invention are shown in FIGS. 1, 2, and 3.

As shown in Figure 1, a magnetic paste made by mixing and kneading magnetic powder such as ferrite with a binding resin and a solvent is extruded into a somewhat thick magnetic material layer 1 in the center, with both ends exposed at the edges. One conductor 2 is laminated by extrusion molding from a conductor paste made by mixing metal or alloy powder with a binding resin and a solvent. Furthermore, a magnetic layer 1 is superimposed on this upper layer to form a green laminate 3 in which the end faces of the conductor 2 are exposed on both edges as shown in FIG. The raw laminate 3 is integrally sintered at a predetermined temperature and connected to the conductor 2 exposed on both end faces as shown in FIG. ' is provided to form an impedance element.

Embodiments of other impedance elements according to the present invention are shown in FIGS. 4, 5, and 6.

As shown in Fig. 4, a plurality of parallel conductors 2゜2/, 2// extruded from conductive paste are placed on top of the magnetic layer 1 extruded from magnetic paste, with both ends exposed at both edges. A raw laminate 3 as shown in FIG. 5 is obtained by superimposing the magnetic material layer 1' on top of the magnetic material layer 1'.

The main body layer 3 is integrally sintered at a predetermined temperature and connected to the conductors 2.2', 2'', respectively, as shown in FIG. A common-mode impedance element that can be surface-mounted is formed.

In these impedance elements or in-phase impedance elements according to the present invention, the magnetic layer 1 is molded by one extrusion, and the number of layers is reduced compared to the conventional method in which a magnetic layer is obtained by laminating and drying a plurality of thin magnetic sheets. do.

FIG. 7 shows an impedance element and an in-phase impedance element manufacturing apparatus according to the present invention.

As shown in the drawing, there is a magnetic material extrusion mechanism 7.7' consisting of two sets of upper and lower magnetic material heads 5.5' and a magnetic paste storage box 6.6' filled with magnetic paste, and a conductive head in the middle of each. 8 and a conductor paste storage box 9 filled with conductor paste, a conveyance mechanism II for feeding them, and pressure rollers 12 and 12' that press and laminate the magnetic layer l and the conductor 2 from above and below. A manufacturing device is formed.

The magnetic paste now extruded from the magnetic head 5 of the magnetic extrusion mechanism 6 becomes the magnetic layer 1 and is transferred to the transport mechanism 11.
Sent by Next, the conductor paste is extruded by the conductor head 8 onto the magnetic layer 1 in the conductor extrusion mechanism 10, and a plurality of conductors 2.2', 2'' are superimposed on the magnetic layer 1.
It is also sent by the transport mechanism 11. Furthermore, the magnetic layer 1' extruded by the magnetic head 5' of the magnetic extrusion mechanism 7' provided at the top is superimposed on the conductors 2.2' and 2'', and finally the pressure roller is applied from above and below. 12.1
2' are laminated and pressed together to form a continuous green laminate 3 in a band shape.

<Effects of the Invention> As described above, according to the present invention, the magnetic layer 1 and the conductor 2 are extruded from the magnetic paste and the conductor paste, respectively, by the manufacturing device, and a consistent and continuous green laminate 3 is manufactured. Therefore, compared to the conventional method of laminating multiple magnetic sheets to obtain a magnetic layer, the lamination process is simpler and more economical. Conductor paste storage box, 10: Conductor extrusion mechanism.

An element is formed. 1
1: Conveyance mechanism, 12.12': Pressure roller.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a green laminate in an embodiment of the impedance element of the present invention, and FIG. 2 is an assembled perspective view of the assembled green laminate in FIG. 1. FIG. 3 is an external perspective view of an impedance element provided with electrode terminals as shown in FIG. An external perspective view of the assembled green laminate in Figure 4,
FIG. 6 is an external perspective view of an in-phase impedance element provided with electrode terminals as shown in FIG. 5, and FIG. 7 is an external configuration diagram showing the configuration of a manufacturing apparatus according to the present invention. Note that 1, I': magnetic layer 2.2', 2//: conductor,
3: Raw laminate, 4.4', 4": Electrode terminal, 5.5':
Magnetic head 1616'*Magnetic paste storage box, 7.7
'Figure 1 Figure 4 Figure 2

Claims (2)

[Claims] 1. Two magnetic layers 1 extruded from a magnetic paste made by mixing and kneading ferromagnetic powder, binding resin, and solvent;
Between 1' and 1', a parallel conductor 2 is extruded from a conductor paste made by mixing and kneading alloy powder, binding resin, and solvent.
, 2', 2'' are stacked together and sintered together, and connected to each of the conductors 2, 2', 2'', and electrode terminals 4, 4', 4'' are connected with conductive material. Impedance element provided. 2. A conductive paste storage box 9 filled with the conductive paste and a conductor are placed between two upper and lower magnetic material extrusion mechanisms 7 and 7' consisting of a magnetic paste storage box 6 filled with the magnetic paste and a magnetic head 5. The impedance element is equipped with a conductor extrusion mechanism 10 consisting of a head 8, a conveyance mechanism 11 for sending out a continuous green laminate 3 extruded from each side, and pressure rollers 12 and 12' for laminating layers under pressure from above and below. Manufacturing equipment.