JPS6316846B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides lead wires connected to electrodes of electronic components;
and a method for connecting lead wires and electrodes.

Conventionally, in electronic components where lead wires and electrodes are connected by soldering, such as ceramic capacitors, the lead wire 1 is cut to a certain length as shown in Figure 1, and the center part is approximately " It was bent into a "U" shape, with both ends 2 bent into a "dog" shape. The lead wire 1 thus formed is attached to the lower part with tape 3 from both sides and used for attaching leads to a ceramic capacitor. In other words, lead wires used in conventional ceramic capacitors have been processed by cutting, bending, etc., and then attached to tape before being attached to the ceramic capacitor. Moreover, in the conventional model, the part bent into a "U" shape in the center and the part attached to the tape are completely unnecessary for actually mounting on the printed circuit board, so they are soldered and the soldered parts are painted with paint. The material was also wasteful as it was discarded after being coated. For example, the lead wire used to connect a ceramic capacitor with a thickness of 0.2 mm and a diameter of 8 mm has a total length of 90 mm, but the length required to actually attach it to a printed circuit board is approximately 20 mm for one electrode, and for both electrodes. 40
Only about mm was needed, and more than half of the total length was cut off.

In addition, as shown on the right side of Fig. 1, conventional ceramic capacitor lead wire connections are made by sandwiching the electrode 5 of the ceramic capacitor 4 at the intersection of both ends 2 of the lead wire 1, applying flux, and then applying a suitable reserve. It was heated and then immersed in molten solder for soldering. In this conventional connection method, no matter how much preheating is done before dipping into the molten solder, the ceramic, which is susceptible to heat shock, can break or crack due to sudden changes in temperature as it is immersed in the molten solder at a high temperature. There were many items that were defective. Furthermore, since conventional connection methods use metals such as silver and copper for the electrodes, during soldering, these electrode metals diffuse and dissolve into the molten solder, reducing the electrode area and worsening the electrical characteristics. Otherwise, an undesirable phenomenon may occur in which the adhesive strength with the lead wire is weakened.

The present invention provides a lead wire that can obtain only the length necessary for mounting on a printed circuit board, and a lead wire connection method that does not cause any defects due to heat shock or diffusion of metal on the electrode surface during soldering. There is a particular thing.

The present invention will be explained below based on the drawings. FIGS. 2a to 2e show examples of lead wires of the present invention. The lead wire of the present invention is a long lead wire in which a fixed amount of solder is placed at regular intervals, and this interval is a length necessary for mounting electronic components on a printed circuit board.

Figure 2 a shows a long lead wire 10 wound with thin resin-cored solder 11a several times, b shows a long lead wire 10 pressed with a ring-shaped thick resin-cored solder 11b to make it flat, and c shows a long lead wire. Two disk solder 11c are made into a sandwich shape with adhesive flux with lead wire 10 in between, d is a long lead wire 10 with granular solder 11d attached,
e is a long lead wire 10 wound with tape-shaped solder 11e.

The lead wire of the present invention is used for connecting electrodes of electronic components, which will be described later. Since a certain amount of solder is installed in advance on the lead wire, the amount of solder that adheres to the electrode is constant, making it a reliable product. can be obtained.

Next, a method for connecting an electronic component and a lead wire, which is another invention using the above-mentioned lead wire of the present invention, will be explained. The connection method of the present invention involves placing two lead wires with a certain amount of solder installed at regular intervals so that the respective solders face each other, sandwiching the electronic component between the solder and melting the solder. This connects electronic components and lead wires.

The above connection method of the present invention will be explained in more detail based on the drawings. FIG. 3 (plan view) and FIG. 4 (perspective view) illustrate the connection method of the present invention for connecting lead wires to ceramic capacitors. 2
The lead wires 10 and 10' of the book are soldered with resin 11a, 11a, ..., 11a', 11a', respectively.
... are wound at a constant interval, and the two lead wires 10, 10' are mounted on the jig 12 so that the respective wound resin-cored solders 11a and 11a' face each other and intersect. It is hung on a shelf. A ceramic capacitor 4 having a metal electrode 5 is inserted between the resin-cored solders 11a and 11a' which are crossed opposite each other, and heated through an electric furnace (not shown) to connect lead wires 10, 10'. and the electrode 5 of the ceramic capacitor 4 are connected by soldering.
At this time, the solder containing resin installed on the lead wire is filled with resin that has a flux effect, so the resin flows out before the solder melts, cleaning the soldered area and improving wetting of the solder. It is something to do.

After soldering, the lead wires and ceramic capacitor taken out from the electric furnace are connected in a daisy chain, so cut the lead wires at each end of the ceramic capacitor to create a ceramic capacitor with leads as shown in Figure 5. There are things you can get.

The above-mentioned connection method of the present invention can heat and melt the solder that has been placed on the lead wire in advance using a gentle heating device such as an electric furnace, making it possible to connect the lead wire to electronic components such as ceramic capacitors that are susceptible to heat shock. It is very suitable for making connections, and since the solder is not large in capacity like a molten solder tank, but only a small amount is used for soldering, there is no need to diffuse and melt the metal on the electrodes. It's something that doesn't exist.

As explained above, the lead wire for electronic components of the present invention is easier to mold than conventional lead wires,
Furthermore, the method for connecting lead wires and electronic components has an excellent effect in that not only does it not cause defects, but it also eliminates the waste of cutting off excess lead wires as in the conventional method.

[Brief explanation of the drawing]

Figure 1 is a conventional lead wire, Figures 2 a to e are examples of the lead wire of the present invention, Figure 3 is a plan view illustrating a method of connecting the lead wire of the present invention and electronic components, and Figure 4 is a perspective view of the same. 5 shows a ceramic capacitor obtained by the present invention. 4... Ceramic capacitor, 10... Lead wire, 11a, 11b, 11c, 11d, 11e...
solder.

Claims (1)

[Claims] 1. A lead wire for electronic components, characterized in that a certain amount of solder is placed at certain intervals. 2. A lead wire for an electronic component according to claim 1, wherein the certain amount of solder installed on the lead wire is wound with resin-cored wire solder. 3. A lead wire for an electronic component according to claim 1, wherein the certain amount of solder installed on the lead wire is a ring-shaped resin-cored solder that is pressed and flattened. 4. The lead wire for electronic components according to claim 1, wherein the certain amount of solder installed on the lead wire is disc solder. 5. The lead wire for electronic components according to claim 1, wherein the certain amount of solder installed on the lead wire is granular solder. 6. The lead wire for electronic components according to claim 1, wherein the certain amount of solder installed on the lead wire is formed by winding tape solder. 7. Two lead wires with a certain amount of solder installed at a certain interval are placed in positions such that the respective solders face each other, an electronic component is sandwiched between the solder, and the electronic component is melted by melting the solder. A method for connecting an electronic component and a lead wire, the method comprising connecting the lead wire and the electronic component.