JPS6025875Y2 - inductance circuit components - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a leadless inductance circuit component.

Conventionally, lead wires 2 made of copper or the like are passed through a cylindrical magnetic body 1 made of ferrite or the like as shown in FIG.
An inductance circuit component 4 is known which is formed by bonding.

Such inductance circuit components 4. is lead wire 2
For example, as shown in FIG. 2, the impedance Z changes depending on the frequency f of the current flowing through the electrode.

On the other hand, leadless circuit components have recently been increasingly used in place of conventional leaded circuit components.

When mounting leadless circuit components on a printed circuit board, it can all be done automatically using an automatic mounting device.

Therefore, it would be extremely convenient if the inductance circuit component described above could be made leadless so that it could be mounted simultaneously with other circuit components.

The present invention was developed in view of these demands, and embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows a first embodiment of the manufacturing process of a leadless injectance circuit component according to the present invention.

First, a cylindrical magnetic body 5 having a coaxial through hole 6 as shown in FIG. 3A is prepared.

Next, as shown in FIGS. 3B and 3C, silver paste 7a is applied to both ends of the circumferential surface of the magnetic body 5, both end surfaces, and the inner circumferential surface of the through hole 6, and then baked and hardened.

Next, as shown in the third diagram E, electrode caps 8 and 9 are fitted to both ends of the magnetic body 5.

This cap is made of a conductive metal made of non-ferrous metal such as copper or brass, and its surface is thinly plated with solder.

The caps 8 and 9 cover the silver layer 7 formed by solidifying the silver paste 7a formed on both ends of the magnetic body 5.
It is fitted in close contact with this silver layer 7.

Note that after fitting the caps 8 and 9, heat treatment is performed as necessary.

Thereby, the caps 8 and 9 are electrically connected through the silver layer 7 formed on both ends of the circumferential surface of the magnetic body 5, both end surfaces, and the inner circumferential surface of the through hole 6.

Next, as shown in FIG. 3F, an insulating resin coating 10 is formed on the entire surface except for the caps 8 and 9, and the leadless injectance circuit component 11 is completed.

FIG. 4 shows a second embodiment of the manufacturing process.

First, the same magnetic material 5 as in FIG. 3A is prepared.

Next, as shown in FIG. 4A, an insulating resin coating 12 is coated on the circumferential surface of the magnetic body 5 except for both ends by printing or the like.

Next, when this magnetic body 5 is plated, as shown in FIG. A plating layer 13 is formed on the surface.

Note 1. The plating layer 13 is formed, for example, as follows.

First, nonconductor plating of copper is applied to both ends and end surfaces of the circumferential surface of the magnetic body 5 in the state shown in FIG. give

Next, solder plating is applied to this copper plating layer, or after 1° of nickel plating is applied, solder plating is applied thereon.

In the solder plating, a solder layer containing, for example, 95% lead and 5% tin is formed with a thickness of, for example, 3 to 4 μm.

Next, caps 8 and 9 are fitted to both ends of the magnetic body 5 shown in FIGS. 4B and 4C in the same manner as in the third drawing, and an insulating resin coating 10 is applied in the same manner as in FIG. 3F to form the leads. The responsivity circuit component 11 is completed.

As described above, in the present invention, a conductive layer (for example, a silver layer) is formed on both ends of the circumferential surface of a cylindrical magnetic body in which a through hole is provided in the axial direction, on both end surfaces, and on the inner surface of the through hole. This is a circuit component in which metal electrode caps are fitted into both ends of the body, and a resin sleeve film is formed on substantially the entire surface except for the caps.

Therefore, according to the present invention, a completely new leadless injectance circuit component can be provided, and by configuring a circuit on a printed circuit board together with other leadless circuit components, a circuit design with new performance can be achieved. be able to.

Furthermore, since magnetic materials are relatively sensitive to heat, if the conventional type shown in Figure 1 were simply made leadless, the magnetic material would be likely to crack due to the high heat generated when soldering it to a printed circuit board. Since it has an insulating resin coating, heat will not be transferred directly to the magnetic material, so there is no risk of it breaking.

Furthermore, since the cap is fitted over the silver layer, it is easy to fit the cap.

Furthermore, since there is an insulating resin coating, the insulation can be sufficiently improved even if there is a wiring pattern of a printed circuit board underneath.

In addition, the cost is low due to high productivity.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional inductance circuit component, Figure 2 is a perspective view of a conventional inductance circuit component.
The figure is a characteristic diagram of an inductance circuit component, FIG. 3 is a perspective view and a cross-sectional side view showing a first embodiment of the manufacturing process of the circuit component according to the present invention, and FIG. 4 is a second embodiment of the manufacturing process. FIG. 2 is a perspective view and a cross-sectional side view. In addition, in the symbols used in the drawings, 5...
・Magnetic material, 6... Through hole, 7... Silver layer, 8, 9... Electrode cap, 11...
It is an inductance circuit component.

Claims (1)

[Scope of utility model registration request] A conductive layer is formed on both ends of the circumferential surface of a cylindrical magnetic body in which a through hole is provided in the axial direction, on both end surfaces, and on the inner surface of the through hole,
A circuit component in which metal electrode caps are fitted into both ends of the magnetic body, and an insulating resin coating is formed on substantially the entire surface except for the electrode caps.