JPS5834993A - Method of mounting electronic part - 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 The present invention provides wiring boards that cannot be connected by soldering;
For example, it relates to a method of attaching electronic components to a substrate wired with carbon.

Conventionally, as low-cost boards, there are boards with carbon wiring instead of Au plating, and boards with the wiring surface covered, but the drawback of these boards is that electronic components cannot be attached by soldering. There is nothing I can do about it.

For this reason, the conventional method for attaching electronic components to this type of board is to place the terminals 2 of the electronic part on the wiring 4 formed on the board 6, as shown in FIG. Electronic components are attached by covering with a film 5 coated with a hot melt adhesive and curing it by heating.

However, this mounting method has the following major drawbacks. That is, in general, the terminal spacing of electronic components and the wiring spacing on the board are very small, so simply placing the terminals on the corresponding wiring will cause the components to be affected by vibrations, wind, or when the film 5 is overturned. Misalignment is likely to occur and reliability is lacking. Therefore, apart from the case where a small amount is manually attached, the above-described conventional attaching method cannot be adopted in an automated line whose purpose is to attach a large amount in a short time.

Furthermore, since the terminals of electronic components and the wiring on the board are simply crimped together, the electrical connection between the two may be completely unreliable as the terminals may come off or be lifted up due to distortion of the board. be.

In view of these conventional drawbacks, the present invention provides a reliable electronic component mounting method that is suitable for use in automated lines.

Below, the method of the present invention will be explained based on the figures.
A conductive hot-melt adhesive 3 as shown in FIG. 2 is applied to a terminal 2 of an electronic component 1 as shown in FIG. Note that since printing technology is required to apply the adhesive to the wiring side of the board, it is easier to apply it to the terminals 2.

Next, the terminals 2 of this electronic component I are pressed together with the corresponding wiring 4 on the board 6, and the component terminals 2 are pressed using the adhesive.
Temporarily fasten it to wire 4.

After temporarily fixing the electronic component 1 to the board 6 in this way, as shown in FIG. Then, after heating and melting that part, it is left to cool.

According to such a mounting method, the component terminal can be temporarily fixed onto the wiring of the board using the conductive hot-melt adhesive. Therefore, it is possible to prevent the component terminals from being displaced due to contact with the component when covering the hot melt adhesive film 5, vibration, or the like.

In addition, the terminals and wiring are not simply connected by crimping as in the past, but are strongly mechanically and electrically connected using a conductive hot-melt adhesive, so even if the board is distorted, the terminals will lift up and come out. There is no risk of that happening.

Furthermore, since the terminals are coated with the conductive hot-melt adhesive, there is a synergistic effect in that oxidation of the terminals can be prevented. Furthermore, hot-melt adhesives belong to low-heat melting adhesives, and are solid in normal state, become fluid when heated and melted, and exhibit adhesive strength by cooling and hardening. Since it is a heat-melting type 100% solids made of plastic resin and does not contain solvent or water, it actually has the property of being fixed in a few seconds to a fraction of a second simply by heating and melting and then allowing it to cool. Therefore, it is most suitable for high-speed mass production on automated lines.

As described above, according to the mounting method according to the present invention, it is possible to attach component terminals to a board to which component terminals cannot be mounted by soldering.
Electronic components can be reliably mounted without causing defects such as disconnection or poor connection due to external factors such as vibration, shock, and board deformation. Additionally, component terminals can be temporarily fixed onto the wiring by applying conductive hot-melt adhesive, which prevents the terminals from shifting during installation. Therefore, they can be used in automated lines for continuous installation. This is possible, and its reliability is certain.

[Brief explanation of drawings]

Figure 1 is a side view of the electronic component, Figure 2 is a diagram of the same electronic component coated with a conductive hot melt adhesive, Figure 3 is a diagram of the electronic component attached to a board, and Figures 4 and 5. 3 is a longitudinal sectional view of the main part of FIG. 3, and FIG. 6 is a diagram for explaining the conventional mounting method. 1 is an electronic component, 2 is a terminal, 3 is a conductive hot melt adhesive, 4 is a wiring, 5 is a hot melt adhesive film, and 6 is a board. Agent Patent Attorney Aihiko Fukushi

Claims (1)

[Claims] 1. In the first step, a conductive hot-melt adhesive is applied to the electronic component terminal, in the second step, the component terminal is pressed onto the predetermined wiring pattern of the board to temporarily fix it, and in the third step, it is temporarily fixed. Cover the adhesive film with Holatome/l/) on top of the fourth
A method for attaching electronic components, characterized in that the covered portion is heated in the process and then allowed to cool.