JPH0365006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of soldering lead wires to an electronic component element, such as a ceramic capacitor, which has electrodes on both sides.

2. Description of the Related Art Conventional methods of soldering lead wires to electronic component elements are as shown in FIGS. 8 to 11, for example. That is, first, as shown in FIG. 8, both ends 2 and 3 of the U-shaped lead wire 1 are bent so as to cross each other. Then, as shown in FIG. 9, an electronic component element 4 having electrodes on both surfaces is inserted and held between the two intersecting tips 2 and 3. Then, as shown in FIG. 10, in this state, both ends 2 and 3 of the lead wire 1 and the electronic component element 4 are immersed in flux 5 and pulled up, and then, as shown in FIG. Dip it into solder 6 and pull it out. Through these steps, the lead wire 1 is soldered to the electronic component element 4. In addition,
The U-shaped lead wire 1 is finally cut at the chain line portion shown in FIG. 11 to form a pair of independent lead wires.

Problems to be Solved by the Invention However, in the conventional method of soldering lead wires to electronic component elements as described above, since the flux 5 adheres to the entire electronic component element 4, the amount used increases and However, there is a problem in that the cleaning work is time-consuming. Furthermore, since the solder 6 adheres to the entire electrode surface of the electronic component element 4, the amount of solder used increases, and the high temperature molten solder 6
Since the electronic component element 4 is immersed in the liquid, cracks may occur in the element due to sudden heat shock, etc.
There is a problem in that the adhesion of solder slag causes deterioration of electrical characteristics such as insulation resistance.

The present invention has been made in view of these points, and provides cost advantages by reducing the amount of flux and solder used, as well as a method for electronic component elements that does not deteriorate electrical characteristics. The purpose of the present invention is to provide a method for soldering lead wires.

Means for Solving the Problem To this end, the present invention includes a step of bending both ends of a U-shaped lead wire so as to cross each other, dipping the ends of the intersecting lead wires in molten solder, A process of attaching solder to both ends of the lead wire by pulling both ends apart from each other from the molten solder, a process of applying flux to both ends of the lead wire with solder attached, a process of removing the flux. By holding the electronic component element between both ends of the attached intersecting lead wires, and by heating and remelting the solder at both ends of the lead wire holding the electronic component element,
This method includes the step of soldering both ends of the lead wire to the electrode surface of the electronic component element.

Function The present invention allows flux and solder to be applied in advance only to the tips of the lead wires, so the amount of flux and solder used can be significantly reduced, and moreover, it is possible to reduce the amount of flux and solder used in the process, in which a sudden heat shock is applied to the electronic component elements. Since there are no cracks, there is no occurrence of cracks or deterioration of electrical characteristics.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings.

First, as shown in FIG.
2, a U-shaped lead wire 13 is prepared.
Both ends 1 of such a U-shaped lead wire 13
1 and 12, for example, as shown in FIG. 2, a center mold 14 and side molds 15 on both sides thereof,
16 so that they cross each other. Then, as shown in FIG. 3, the tips 11 and 12 of the intersecting lead wires 13 are immersed in the molten solder 17, and after a predetermined period of time have elapsed, they are pulled upward and the fourth
As shown in the figure, solder 17' is applied to the tips 11 and 12.
Attach. Note that if the intersecting tips 11 and 12 of the lead wires 13 are in contact with each other or are very close to each other, if you apply solder as is, the tips 11 and 12 will be pinched, which may cause damage later. This will interfere with the process. Therefore, if there is a risk of such problems occurring, use molten solder 1.
Before immersing it in the molten solder 17, it should be plastically deformed in advance so that the tips 11 and 12 separate from each other, or when it is pulled up from the molten solder 17,
It is necessary to apply an external force so that both tips 11 and 12 are separated from each other. By doing this, solder can be applied independently to each other without causing a solder bridge between the ends 11 and 12. Furthermore, if the lead wire 13 has been treated with solder plating or the like, it may be immersed in the molten solder 17 as it is, but if it has not been subjected to such treatment or the surface is contaminated, Before dipping into the molten solder 17, it is necessary to apply flux in advance. Furthermore, in order to increase the contact area with electronic component elements, for example, both ends 11 and 1 of the lead wire 13 are
2 so as to cross each other, a flat plate is interposed between the tip portions 11 and 12, and pressing is performed from both sides of the plate, thereby forming both tip portions 11 and 1.
2 should be formed into a flat shape.

In this way, after the solder 17' has adhered to both ends 11 and 12 of the lead wire 13 where they intersect, the ends 11 and 12 are immersed in flux 18 and pulled up as shown in FIG. . after that,
As shown in FIG. 6, the two intersecting tips 11,1
An electronic component element 20 having electrodes 19 on both sides between 2
Insert. At this time, if the tips 11 and 12 are in contact with each other or if there is only a slight gap, the electronic component element 20 can be held elastically between the tips 11 and 12, so there is no problem. There isn't. However, if the gap between the two end portions 11 and 12 is large, the electronic component element cannot be held, so it is necessary to narrow the gap. In order to narrow the gap between the two tips 11 and 12, for example,
As disclosed in the publication, the tip portion 11,
After inserting the electronic component element 20 between 12, the electronic component element 20 may be rotated by 180 degrees so that the positions of the intersecting tips 11 and 12 are exchanged with each other. After the electronic component element 20 is held between both ends 11 and 12 of the lead wire 13 in this way, it is heated in a heating furnace or the like, and both ends 11 and 12 are heated.
The solder 17' adhering to the solder 17' is remelted. As a result, the lead wire 13 is soldered to the electrode surface of the electronic component element 20. Thereafter, if necessary, the electronic component element 20 is covered with an exterior material, and the lead wires 13 are cut at the chain line positions shown in FIG. 6 to form independent lead wires. Note that a large number of lead wires 13 are arranged at equal pitches on a long mount 21 as shown in FIG.
If it is fixed at 2, the series of steps described above can be performed continuously, making it extremely suitable for mass production.

Effects of the Invention Since the method of soldering lead wires to electronic component elements of the present invention includes the steps described above, the amount of flux and solder used can be extremely small, reducing costs. Moreover, it has excellent effects in that it does not cause cracks or deteriorate electrical characteristics.

[Brief explanation of drawings]

1 to 7 are diagrams for explaining each step of a method of soldering a lead wire to an electronic component element according to an embodiment of the present invention, and FIGS. 8 to 11 are diagrams for explaining each step of a conventional example. It is a figure for explaining. 11, 12...Tip, 13...Lead wire, 1
4... Center mold, 15, 16... Side mold, 17, 17'... Solder, 18... Flux,
19... Electrode, 20... Electronic component element, 21...
Mounting paper, 22...Adhesive tape.

Claims (1)

[Scope of Claims] 1. A method of soldering a lead wire to an electronic component element having electrodes on both sides, the method comprising: (a) both ends of a U-shaped lead wire; The process of folding parts so that they cross each other. (b) A process of attaching solder to both ends of the lead wires by immersing both ends of the intersecting lead wires in molten solder and pulling them out of the molten solder in a state where they are separated from each other. . (c) The process of applying flux to both ends of the lead wire with solder attached. (d) A step in which an electronic component element is inserted between both ends of the crossed lead wires to which flux is attached, and the electronic component element is held between the two ends. (e) A step of soldering both ends of the lead wire to the electrode surface of the electronic component element by heating and remelting the solder at both ends of the lead wire holding the electronic component element. A method of soldering lead wires to electronic component elements, including.