JPH08306571A - Manufacture of chip-like inductor and inductor array - Google Patents

Abstract

PURPOSE: To provide a high impedance and compact chip-like inductor by forming a connection electrode for connecting a plurality of linear lead wires in series in a circumference of a magnetic core of a base and forming an external electrode to be connected to both linear terminals of a plurality of linear lead wires in both edge faces of a magnetic core. CONSTITUTION: A plurality of parallel linear lead wires 6 form a rod-like molded item 9 enclosed with a kneading material 8 by an extruder 5. After an inductor base aggregate is prepared by burning the molded item 9, it is cut to a specified length in a length direction of a linear lead wire for preparing an induct base 10. Lead wires 21 to 24 are buried in a magnetic core 1 of the induct base 10 and both ends of each are exposed in a front and a rear of the magnetic core 1. Then, silver paste is applied to a front, a rear and both edge faces of the magnetic core 1 and burned for forming connection electrodes 31 , 32 , 33 and external electrodes 41 , 42 . The lead wires 21 to 24 of the base 10 are connected in series and connected to the external electrodes 41 , 42 .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact and high-impedance chip-shaped inductor and a method for manufacturing an inductor chip.

[0002]

2. Description of the Related Art Conventionally, small-sized high impedance chip-shaped inductors and inductor arrays are known.

[0003]

The chip-shaped inductor and inductor array described above are widely used in electronic equipment, and it is desired to reduce the cost thereof as much as possible.

The present invention has been made in view of such circumstances.

[0005]

In order to achieve the above object, the present invention provides a plurality of linear conductors arranged in parallel at a predetermined interval in an extruder as described in claim 1. The kneading material obtained by kneading the magnetic raw material powder and the binder together with the kneading material is fed into the kneading material, and the extruder is used to form a rod-shaped molding in which the plurality of parallel linear wires are surrounded by the kneading material. After forming a green body aggregate by firing the molded body to cut a predetermined length in the length direction of the plurality of conductors to create a plurality of bases, on the peripheral surface of the magnetic core of the base, the A chip-shaped inductor is formed by forming connection electrodes for connecting a plurality of linear conductors in series and forming external electrodes on both end faces of the magnetic core for connecting to both terminals of the plurality of linear conductors connected in series. It is characterized in that it is manufactured, and the element as described in claim 2. Of the outer surface of the magnetic core, characterized by manufacturing a plurality of forming external electrodes inductor arrays respectively connected to both terminals of the plurality of linear conductors.

[0006]

According to the present invention, a plurality of linear conductors are arranged in parallel at a predetermined interval and fed into an extruder, and a kneading material obtained by kneading a raw material powder of a magnetic material and a binder is fed and extrusion molding is performed. Forming a rod-shaped molded body in which the plurality of linear conductors arranged in parallel by a machine is surrounded by a kneading material, and firing the molded body to form an inductor body assembly or an inductor array body assembly. A plurality of inductor bodies or inductor array bodies are formed at one time by cutting the linear conductor wire into a predetermined length in the length direction. Thus, on the peripheral surface of the magnetic core of this individual inductor body,
A plurality of chip-shaped inductors are created by forming connection electrodes that connect a plurality of conductive wires in series, on both end surfaces of the magnetic core, and forming external electrodes that connect to both ends of the plurality of conductive wires that are connected in series, Further, a plurality of chip-shaped inductor arrays are formed by forming a plurality of external electrodes respectively connected to both ends of the plurality of linear conductive wires on the outer surface of the magnetic core of each individual inductor array base.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a chip-shaped inductor manufactured by the manufacturing method according to the present invention. In the figure, 1
It is a magnetic core made of ferrite having a rectangular parallelepiped shape, including, for example, four conductors 2 _1, 2 _2, 2 _3, 2 ₄ is embedded is arranged in parallel at predetermined intervals, conductor lines 2 ₁ and 2 ₂
Due to the connection electrode 3 ₁ formed on the rear surface of the magnetic core 1,
The conductors 2 ₂ and 2 ₃ are connected by a connecting electrode 3 ₂ formed on the front surface of the magnetic core 1, and the conductors 2 ₃ and 2 ₄ are connected by a connecting electrode 3 ₃ formed on the rear surface of the magnetic core 1 and connected in series. The ends of the conductive wires 2 ₁ and 2 ₄ are connected to the external electrodes 4 ₁ and 4 ₂ formed on both end surfaces of the magnetic core 1. According to the configuration of this inductor, the conductive wires 2 ₁ , 2 ₂ ,
All of 2 ₃ and 2 ₄ are embedded in the magnetic core 1, and the magnetic flux generated by the long conducting wire does not flow into the magnetic core 1 and leaks to the outside, so that a small inductor having a large impedance can be obtained.

Next, a method of manufacturing this chip-shaped inductor will be described.

In FIG. 2, reference numeral 5 denotes an extrusion molding machine, into which four long linear conductors 6 are fed from four conductor feeding portions 5a and kneading machines are fed from a kneading material feeding portion 5b. When the kneading material 8 obtained by uniformly kneading the binder S and the magnetic material raw material powder B at a proper mixing ratio in 7 is supplied under pressure, four linear conductor wires are output from the die 5c which is the outlet of the molding machine 5. A molded body 9 made of a kneaded material having a desired sectional shape, for example, a rectangular shape, containing 6 is extruded at a speed of 30 m / min, for example. This molded body 9
For example, after being dried by a dryer (not shown), it is cut according to the size of a firing furnace (not shown) or the shape of a setter (not shown) laid thereunder. And this is 60
After firing at 0 to 1000 ° C., for example 900 ° C., to prepare an inductor base material assembly, this is cut by a cutter in the lengthwise direction of the linear conductor wire 6 according to the dimensions of each inductor. Reference numeral 10 is an inductor body cut by a cutter. The inductor green body 10, conductors ₂₁ to ₂₄ is embedded in the magnetic core 1, as described above, both ends are exposed to the front and rear surfaces of the magnetic core 1. Then, a silver paste composed of silver powder and a solvent is applied to the front surface, rear surface and both end surfaces of the magnetic core 1 of the inductor base 10 and baked to form connection electrodes 3 ₁ , 3 ₂ , 3 ₃ and external electrodes 4 ₁ , 4
Form ₂ . Thus, the four conductors 2 ₁ to 2 ₄ of the inductor body 10 are connected in series to form the external electrodes 4 ₁ and 4 _2.
Connected to. Nickel plating and solder plating are applied on the silver layers of the external electrodes 4 ₁ , 4 ₂ .

FIG. 3 shows an inductor array manufactured by the manufacturing method according to the present invention. In the figure, 1
Is a magnetic core made of rectangular parallelepiped ferrite, for example, four linear conductors 2 ₁ , 2 ₂ , 2 ₃ , 2 ₄
Are arranged in parallel at predetermined intervals and embedded, and the magnetic core 1
On the front and back surfaces of the four linear conductors 2 _{1 to} 2 ₄
Four external electrodes 4 ₁ , 4 ₂ , 4 ₃ , which are connected to the terminals of
4 ₄ are formed respectively. According to the configuration of this inductor array, the conductors 2 ₁ , 2 ₂ , 2 ₃ , 2 ₄ are all embedded in the magnetic core 1, and the conductors 2 ₁ , 2 ₂ ,
The magnetic flux generated by 2 ₃ and 2 ₄ flows in the magnetic core 1,
Since there is no leakage to the outside, the impedance of each of the conductors 2 _{1 to} 2 ₄ is large, and a small inductor array can be obtained.

This inductor array is formed in the magnetic core 1 on the front and rear surfaces of the magnetic core 1 of the inductor array base manufactured by the same manufacturing method as the manufacturing method of the chip-shaped inductor base 10 described with reference to FIG. buried conductors ₂₁ to ₂₄ of the front and silver paste made of silver powder and solvent to be connected respectively to the exposed ends to the rear of the applied baking, nickel plating and solder plating on the silver layer And a plurality of external electrodes 4 ₁ , 4 ₂ ,
Manufactured by forming 4 ₃ and 4 ₄ .

[0013]

According to the present invention, according to the above-mentioned structure, a high-impedance and small-sized chip-shaped inductor and inductor array can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a perspective view of a chip-shaped inductor manufactured by a manufacturing method according to the present invention.

FIG. 2 is a diagram for explaining an embodiment of the present invention.

FIG. 3 is a perspective view of an inductor array manufactured by a manufacturing method according to the present invention.

[Explanation of symbols]

1 magnetic core 2 _{1 to} 2 ₄ conducting wire 3 ₁ 3 ₂ 3 ₃ connection electrode 4 ₁ to _{4 4}
External electrode 5 Extrusion molding machine 6 Long straight conductor wire 7 Kneading machine 8 Kneading material 9 Molded body 10 Inductor base (inductor array base)

Claims (2)

[Claims] 1. A plurality of linear conductors are arranged in parallel at a predetermined interval and fed into an extrusion molding machine, and a kneading material obtained by kneading a magnetic material raw material powder and a binder is fed into the extrusion molding machine. , Forming a rod-shaped molded body in which the plurality of linear conductors arranged in parallel are surrounded by a kneading material, and firing the molded body to form an inductor base assembly, which is arranged in the longitudinal direction of the linear conductors. A plurality of inductor bodies are created by cutting into a predetermined length, and connecting electrodes for connecting the plurality of linear conductor wires in series are formed on the peripheral surface of the magnetic core of the inductor body, and both end surfaces of the magnetic core are formed. A method of manufacturing a chip-shaped inductor, wherein external electrodes connected to both ends of a plurality of linear conductors connected in series are formed on the. 2. A plurality of linear conductors are arranged in parallel at a predetermined interval and fed into an extrusion molding machine, and at the same time, a kneading material obtained by kneading a magnetic material powder and a binder is fed into the extrusion molding machine. Forming a rod-shaped molded body in which the plurality of parallel linear conductors are surrounded by a kneading material and firing the molded body to form an inductor array base assembly, and then forming this into the length of the linear conductive wire. A plurality of inductor array bases are created by cutting into a predetermined length in the direction, and a plurality of external electrodes respectively connected to both ends of the plurality of linear conductors are formed on the outer surface of the magnetic core of the inductor array bases. A method for manufacturing an inductor array, which is characterized by being formed.