JPS59136990A - Reflow soldering method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a glue flow soldering method for soldering small electronic components and the like.

(bl Prior Art and Its Disadvantages) In general, when soldering electronic components, for example soldering printed wiring boards, when soldering lead wires of CR components to parts, it is more efficient than soldering with a solder gauntlet, and flow soldering The soldering paste is usually applied to the parts to be soldered using a screen printing method or a stamping method.

FIG. 1 shows the procedure for supplying paste solder and performing reflow soldering using the former screen printing method. A mask 2 that masks areas other than the parts to which solder is to be applied is placed on the electronic component board 1, and paste solder 3 is applied along the surface of the mask 2 with a squeegee 4 (see Fig. 1).
A)). By applying the solder paste with the squeegee 4 in this manner, the solder paste 3 is applied only to the portions not masked by the mask 2 (FIG. 1(B)). Next, with the paste solder screen printed, electronic components 5 to be soldered are placed on the paste solder 3 as shown in FIG. 1(C), and the board 1 is placed in a reflow oven to melt the paste solder. As a result, the electronic component 5 is soldered to the board 1 with the solder 6.

On the other hand, FIG. 2 shows the procedure for supplying paste solder using the latter stamping method. Apply paste solder 8 to the surface of the flat base 7, and then attach the stick 9 to the flat base 7.
to adhere the paste solder to the tip of the stick 9 (Fig. 2 (A)), move the stick 9 with the paste solder 8 attached onto the electronic component board 10, and press the tip against the board 10. Paste solder 8 is attached to the substrate 10 (FIGS. 2(B) and 2(C)).

Next, as shown in FIG. 2(C), with the paste solder 8 attached to the desired location on the board 10, the paste solder 8 An electronic component is placed on top and heated in a reflow oven to melt the solder paste 8. As a result, the mounted electronic components and the board 10 are soldered.

However, when supplying paste solder using the screen printing method, it is required that the place where the paste solder is applied is flat, so if the parts to be soldered are arranged three-dimensionally and the place where the paste is applied is uneven, paste solder cannot be used. could not be applied. Further, when supplying paste solder by the stamping method, the amount of paste solder that adheres to the stick 9 is not constant, making it difficult to control the amount of paste solder supplied. In this way, with the conventional glue flow soldering method, there was a problem with the supply of paste solder, so it was difficult to solder electronic components that were arranged in a complicated manner (=
In particular, soldering in a mass production line for electronic components cannot be applied to the process because J-ke cannot be performed accurately and the scope of application is limited.

fc) Purpose of the Invention This invention was made in view of the above-mentioned conventional drawbacks.
It is an object of the present invention to provide a reflow soldering method that can perform soldering reliably and has a wide range of applications.

(d+ Structure and Effect of the Invention This invention performs soldering of electronic components by dropping cream paste solder onto a desired location where electronic components are to be soldered, and then heating and melting the dropped paste solder. This is how it was done.

According to this invention, soldering can be done by dropping creamy paste solder onto the parts, which enables the supply of paste solder to the parts where electronic parts are arranged three-dimensionally, and also by dropping creamy paste solder onto the parts. By adjusting the amount, the amount of solder paste supplied can be accurately controlled, so even if electronic components are arranged in a complex manner, soldering can be performed stably and reliably, and it can be applied to a wide range of components. In particular, there is an advantage that automation of the soldering process in a mass production line for many types of electronic components can be easily realized.

(El Embodiment Figure 3 is a flow soldering method according to the present invention. The soldering method is a soldering procedure explanatory diagram. This example shows a lead wire connected to an electrode 14 formed on a substrate 11 of an electronic component. This is a case where the terminal 15 of the
), the terminal 15 is placed on the electrode 14, and cream paste solder 13 is dropped from above. Best solder 13 stripes, so-called dispenser or port.
A desired amount is dripped from a nozzle 12 of a dripping device called a tuter. The nozzle 12 is fixed in position using an X-Y table or the like. The amount of solder paste 13 dripped from the nozzle 12 is controlled by the internal pressure applied to the nozzle 12 and the pressurization time.

Electrode 14 by said dispenser or potter.
and dropping paste solder 13 onto the surface of the terminal 15,
As shown in FIG. 3(B), paste solder 16 is applied to the entire portion of the terminal 150 to be soldered. After the paste solder is supplied in this manner, it is heated in a reflow oven to melt the paste solder. The paste solder dropped onto the surface of the terminal 15 by heating melts and flows toward the electrode 14, and the third
As shown in Figure (C), the electrode 144 of the terminal 15 is soldered with solder 17 on the side surface.

As mentioned above, the paste solder is supplied to the parts to be soldered by the dispenser or botter, so it is difficult to accurately supply the paste solder to the parts with some unevenness or to the parts with minute soldering. can. Further, the amount of solder paste supplied can be accurately controlled by the amount of dripping.

In this way, when soldering any electronic component, it is possible to supply the appropriate amount of paste solder to the desired location, so this reflow soldering method is less complicated when applying the process to an electronic component production line. Even if there are many types of electronic components with various shapes, and even if the mounting density is high, the soldering work can be easily automated.

Note that a heating device using infrared rays as a heat source may be used as the heating means for melting the solder paste, and the infrared rays may be irradiated only to the part to be soldered to avoid thermal damage to other parts. Alternatively, a heating device using a laser beam, hot air, or the like as a heat source may be used.

[Brief explanation of drawings]

Figures 1 (A) to (D) are step-by-step diagrams for explaining the conventional glue-flow soldering method in which paste solder is supplied by a screen printing method, and Figures 2 (A) to (D)
C) is a stamping procedure explanatory diagram for explaining the conventional glue flow soldering method in which paste solder is supplied by a stamping method, and Figures 3 (A) to (C) are stamping procedure explanatory diagrams for explaining the paste soldering method of the present invention. This is a soldering process step explanatory diagram for explaining the soldering process. 11 - (electronic component) board, 12 - (cream paste solder dropping device) nozzle, 13 - cream paste solder, 14 - electrode, 15 - terminal. Applicant Tateishi Electric Co., Ltd. Agent Patent Attorney Hisao Komori 9 □12 ・N, 3! ″／［ Z co

Claims (1)

[Claims] (1) Reflow soldering is a method in which creamy paste solder is dropped onto the desired location where electronic components are to be soldered, and then heated to melt the dropped paste solder and solder the electronic components.