JPH06196346A - Manufacture of electronic component with lead terminal - Google Patents

Abstract

PURPOSE:To suppress generation of a solder ball at a lead terminal by covering an electronic component body in which the terminal is axially extended with an insulating sheath, heating it at a temperature of a melting point or higher of solder, feeding excess solder of a base end out of the sheath, and then bending the terminal along the sheath. CONSTITUTION:An inductor body 1 is formed by winding a winding 3 on a drum-shaped core 2, binding its end 4 with a base ends of lead terminals 7, 7 fixed in recesses 5, 5 formed on both end faces of the core 2 with adhesive 6 and conductively fixing with solder 8. An insulator of resin including the base end is covered with insulating sheath 9 by molding. Then, excess solder 8 of the base end of the terminal 7 is fed externally between the terminal 7 and the sheath 9, and so covered as to become a thin layer by extending toward the outer end of the terminal 7. Thereafter, the terminal 7 is bent along the sheath 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component such as an inductor in which a main body of the electronic component is covered with an insulating outer casing and lead terminals are led out from the insulating outer casing.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, an inductor body a is covered with an insulating outer package b formed by molding an insulating material such as resin, and lead terminals c attached to both ends of the inductor body a. There is known a chip-type inductor in which is derived from the insulating outer package b and bent along the surface of the insulating outer package b (Japanese Utility Model Laid-Open No. 2-101524). The chip inductor is mounted on a circuit board d, and the lead terminals c are conductively fixed to the conductive lands e on the circuit board d by solder f.

[0003]

When soldering the conventional chip-type inductor, for example, to the conductive land e of the circuit board d, the reflow soldering method is generally adopted. According to this method, the solder h applied to the connection portion between the winding terminal g and the lead terminal c inside the insulating outer package b.
May be re-melted by the heat at the time of reflow soldering and may flow out of the insulating sheath b through the gap between the insulating sheath b and the lead terminal c.
If the surface tension is high, the solder h that has flowed out becomes spherical and solidifies there (hereinafter referred to as solder ball j). Since this solder ball j is weakly fixed to the bent portion i of the lead terminal c,
If it peeled off easily and entered between the lead terminals of an electronic component such as an IC chip on the circuit board d, there was a risk of causing an electrical short circuit.

The present invention has been made in order to solve such a conventional problem, and is an electronic component which can suppress the generation of solder balls at the lead terminals when the lead terminals are soldered to the conductive portions of the circuit board. It is an object of the invention to provide a manufacturing method.

[0005]

In order to achieve the above-mentioned object, the present invention is attached to an electronic component body covered with an insulating exterior body, is led out from the insulating exterior body, and extends along the insulating exterior body. In the method of manufacturing an electronic component, which has a lead terminal bent as described above, the electronic component body is electrically connected to the base end portion of the lead terminal in the insulating outer package by soldering,
The electronic component body, in which the lead terminals were led out in the axial direction, was covered with an insulating exterior body, and then the electronic component body was heated at a temperature equal to or higher than the melting point of the solder to allow excess solder at the base end to flow out of the insulating exterior body. After that, the lead terminal is bent along the insulating exterior body.

[0006]

The electronic component body electrically connected to the lead terminal at its base end by soldering is insulated with the lead terminal extending in the axial direction of the electronic component body, including the base end portion. After coating with the body, heating the electronic component body,
Excessive solder at the base end flows out from between the insulating outer package and the lead terminal and spreads toward the end of the linear lead terminal. After the solder is solidified, the lead terminals are bent along the insulating exterior body and formed into a final shape, for example, a chip-shaped electronic component.

For example, when the chip-shaped electronic component is soldered to the conductive land of the circuit board by the reflow soldering method, the solder at the base end in the insulating outer package is remelted, but the excess solder has already flowed out. Therefore, the solder does not flow out to the outside, and a solder ball is not formed in the bent portion of the lead terminal.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention applied to an inductor will be described below with reference to the drawings.

FIG. 1 shows the inductor before molding the lead terminals.

In FIG. 1, reference numeral 1 denotes an inductor body, which has a winding 3 wound around a drum-shaped magnetic core 2 and ends 4 of which are recesses 5 formed on both end surfaces of the magnetic core 2.
5, lead terminals 7, 7 fixed by an adhesive 6
It is formed by being entangled with the base end portion of the above and electrically conductively fixed by the solder 8, and is covered with an insulating outer casing 9 formed by molding with an insulating material such as resin including the base end portion.

The lead terminals 7, 7 are flattened outside the base end portion and extend linearly in the axial direction of the magnetic core 2 when the insulating sheath 9 is covered.

The inductor 10 shown in FIG. 1 is placed on a hot plate 11 as shown in FIG. 2, or is placed in hot air 12 as shown in FIG.
Alternatively, as shown in FIG. 4, when heated near the far infrared heater 13, as shown in FIG. 5, the excess solder 8 at the base end of the lead terminal 7 is between the lead terminal 7 and the insulating outer package 9. Flows out to the outside, spreads toward the outer end portion of the lead terminal 7, and is applied as a thin layer.

Thereafter, as shown in FIG. 6, the lead terminal 7 is bent along the insulating outer package 9, and the end portion thereof is further bent toward the insulating outer package 9, and the bent portion is used as the electrode 14. .
Then, place the inductor 10 on the circuit board 15,
The electrode 14 is heated after being aligned with the conductive land 16 of the circuit board 15, and the electrode 14 is conductively fixed to the conductive land 16 by the cream solder 17. At this time, no solder ball is formed on the lead terminal 7.

The present invention can be applied not only to inductors, but also to capacitors and other electronic parts, and can be applied to radial lead type electronic parts as well as the surface mount chip type electronic parts as in the above-mentioned embodiment.

[0015]

Since the present invention is configured as described above, when the electronic component is mounted on the circuit board and the lead terminal is conductively fixed to the conductive land of the circuit board by the reflow soldering method, the lead terminal This has an effect that a solder ball is not generated due to the outflow solder in the bent portion.

[Brief description of drawings]

FIG. 1 is a sectional view of an inductor before molding a lead terminal.

2 is an illustration of a first method of heating the inductor of FIG.

3 is an illustration of a second method of heating the inductor of FIG.

4 is an illustration of a third method of heating the inductor of FIG.

5 is a cross-sectional view of a portion of the inductor after heating the inductor of FIG.

FIG. 6 is a perspective view showing a state in which an inductor manufactured according to the present invention is mounted on a circuit board and conductively fixed.

FIG. 7 is a sectional view showing the same state as in FIG.

FIG. 8 is a partial cross-sectional view of a conventional electronic component for explaining the problem.

[Explanation of symbols]

 1 Inductor Main Body 7 Lead Terminal 8 Solder 9 Insulation Body 10 Inductor 11 Hot Plate 12 Hot Air 13 Far Infrared Heater 14 Electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Ogawa 6-16-20 Ueno, Taito-ku, Tokyo Taiyo Induction Co., Ltd.

Claims (1)

[Claims] 1. A lead terminal attached to an electronic component body covered with an insulating exterior body, led out from the insulating exterior body, and bent along the insulating exterior body, wherein the electronic component body is an insulating exterior body. In a method of manufacturing an electronic component electrically connected to a base end portion of a lead terminal in a body by soldering, an electronic component body in which a lead terminal is axially led out is covered with an insulating exterior body, and then the electronic component body is An electronic component having a lead terminal, characterized in that the lead terminal is bent along the insulating exterior body after being heated at a temperature equal to or higher than the melting point of the solder to cause excess solder at the base end portion to flow out of the insulating exterior body. Manufacturing method.