JPH0342069A - Device for applying adhesive agent - Google Patents

Abstract

PURPOSE:To apply an adhesive agent in a prescribed amt. to coating surfaces of an extremely small width by disposing two pieces of nozzles each having an elliptical sectional shape apart a prescribed spacing in such a manner that the longitudinal directions of the respective nozzles is linear and discharging the adhesive agent therefrom. CONSTITUTION:Two pieces of the nozzles 15, 16 each having the elliptical sectional shape are disposed apart the prescribed spacing (the spacing at which the distance between the axial centers is, for example, 1.0mm) to the bottom end part of a container 23 housing the adhesive agent 5 in such a manner that the longitudinal directions thereof are linear. An air pressure is applied to the container 23 to discharge the prescribed amt. of the adhesive agent 5 from the two nozzles 15, 16. The adhesive agent 15 is applied at the two points within the spacing between foot prints 11 and 11 so as to build up with the coating surfaces meeting the sectional shapes of the respective nozzles 15, 16. The generation of a soldering defect by the bleeding of the adhesive agent out of the coating regions is prevented.

Description

[Detailed Description of the Invention] [Summary] Regarding an adhesive application device, it is possible to apply a predetermined amount of adhesive to a coating area of minute width, and prevents soldering failure due to adhesive protruding from the application area N. An adhesive applicator configured to discharge a predetermined amount of adhesive from the lower end of a container containing the adhesive. Two nozzles each having an oval cross-sectional shape are arranged at the lower end of the container so as to be separated from each other so that the major diameter direction of each nozzle is in a straight line, and the adhesive is discharged from each nozzle. It is composed of features that are designed to do so.

[Industrial application field]

The present invention relates to an adhesive coating device, and relates to surface mounting technology (S
When manufacturing component mounting boards using MT, it is used to apply adhesive for temporary fixing of electronic components before soldering.

S MT (Surface Mount Techn.
Technology) is widely used because it allows electronic devices to be made lighter, thinner, shorter, smaller, higher in performance, higher in quality, and lower in price.

In recent years, as the size of electronic components mounted on printed circuit boards has progressed through SMT, strict precision has become required in the application conditions such as the amount of application and the application position, even when applying adhesive for temporarily fixing components. It's here.

[Conventional technology]

FIG. 4 is a perspective view showing a conventional coating device 2, and FIG. 5 is a perspective view showing a conventional coating device 2.
FIG. 6 is a partially sectional front view showing an enlarged view of the nozzle 25 shown in the figure, and FIG. 6 is a sectional view taken along the line Vl--Vl in FIG.

In these figures, the coating device 2 is arranged in the direction of arrow M1 (Y
The substrate mounting table 21 is movable in the direction of arrow M2 (
The adhesive 5 has a coating pad 22 that is movable in the vertical direction, and a storage container 23 for the adhesive 5 is attached below the coating pad 22 so as to be movable in the vertical direction.

The storage container 23 includes an inner container 23a made of resin filled with the adhesive 5, and a holder 23b surrounding the inner container 23a. A nozzle unit 24 having one cylindrical nozzle 25 and two stopper pins 26 and 27 is attached to the lower end of the storage container 23. The tips of the stopper pins 26 and 27 protrude downward by a slight length G (for example, 0.2 mm) than the tip of the nozzle 25.

The nozzle 25 communicates with the lower end opening 23C of the inner container 23a, and a predetermined amount of the adhesive 5 is discharged from the nozzle 25 by appropriately applying air pressure to the inside of the inner container 23a.

The coating device 2 having the above configuration is used to apply adhesive for temporary fixing of electronic components, which is necessary for soldering and connecting a large number of electronic components at once when manufacturing a component mounting board using SMT.

Application of the adhesive 5 is performed as follows.

First, the printed circuit board 10 is placed on the board mounting table 21 with the surface to which the adhesive 5 is to be applied facing upward. On the surface of the printed circuit board 10 (both the front and back sides for a double-sided mounting board),
A pair of conductor patterns (footprints) 11, which serve as connection pads for solder connection, are provided at various locations corresponding to the mounting positions of the mounted components.

Next, by appropriately moving the board mounting table 21 and the coating pad 22, the nozzle 25 is placed above the coating position on the printed circuit board 10, that is, in the gap between the pair of footprints 11 and 11 corresponding to one mounted component. (applied area) above the center.

Subsequently, the storage container 23 is lowered until the tips of the stopper pins 26 and 27 come into contact with the surface of the printed circuit board IO side, and
A predetermined amount of adhesive 5 is discharged and applied to the surface of the printed circuit board 10.

When the application at one location is completed, the movement of the nozzle 25 and the discharge of the adhesive 5 are repeated to sequentially apply the adhesive 5 to pairs of footprints 11 at various locations on the printed circuit board 10.

As is well known, the printed circuit board 10 that has been coated with the adhesive 5 undergoes an electronic component mounting process, an adhesive curing process, and a wave soldering (dipping) process to become a component mounting board (circuit board). be completed.

[Problem to be solved by the invention]

The cross-sectional shape of the nozzle 25 of the conventional applicator 2 is circular (for example, the inner diameter is 0.5 m and the outer diameter is 0.8 m), and the adhesive is applied to one point (one place) for one electronic component. 5 was to be applied.

For this reason, for example, between a pair of footprints 11.11 provided to accommodate a minute electronic component with a bottom surface dimension of 1.25m*X2.0-, a predetermined amount of space is required to prevent the electronic component from coming off. When the adhesive 5 is applied, the width of the gap between the footprints 11 is narrow (for example, about 0.8 m)
Therefore, the applied adhesive 5 is 11.11
There was a problem in that it protruded from the gap toward the footprint ll side.

FIGS. 7(a) and 7(b) are diagrams showing the mounting state of conventional electronic components. Figure 7(a) is a cross-sectional front view;
Figure (b) is a plan view.

As mentioned above, the applied adhesive 5 is bonded (fundoblin) 11
If it protrudes to the side, the printed base F after soldering has gone through the process.
At i10, as shown in FIG. 7, the adhesive 5 enters between each footprint 11 and the electronic component 3 mounted so as to straddle a pair of footprints 11, and the footprint 11 and The electrical connection with the electronic component 3 becomes defective. Note that solder is not illustrated in FIG. 7(b).

In order to prevent the adhesive 5 from overflowing, if the applied amount of the adhesive 5 is reduced, the adhesive strength decreases as the adhesive area decreases, and the electronic component 3 mounted before soldering may separate from the printed circuit board 10. I end up.

In view of the above-mentioned problems, the present invention makes it possible to apply a predetermined amount of adhesive to an application area with a minute width, and prevents soldering defects caused by adhesive protruding from the application area. The purpose of the present invention is to provide a coating device for a chemical agent.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention has been made as shown in FIGS. 1 and 2.
As shown in the figure, an adhesive applicator 1 is configured to discharge a predetermined amount of the adhesive 5 from the lower end of a container 23 containing the adhesive 5. , two nozzles 15.16 each having an oval cross-sectional shape are arranged so as to be separated from each other so that the long axis direction of each nozzle 15°16 is in a straight line, and the adhesive 5 is discharged from each nozzle 15.16. It is composed of features that are designed to do so.

[For production]

The adhesive 5 stored in the container 23 is passed through two nozzles 15.
16 and is discharged onto the surface to be coated.

The adhesive 5 is distributed and applied to the surface to be applied at two points (2M, 11 places) so as to correspond to the arrangement and cross-sectional shape of each nozzle 15, 16.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing the main parts of a coating device 1 according to the present invention;
FIG. 2 is a sectional view taken along the line ■--■ in FIG. 1. In these figures, the same components as in FIG. 5 are given the same reference numerals.

The basic configuration of the coating device 1 is almost the same as the coating device 2 shown in FIG. However, in the coating device 1, the storage container 23 is attached to the coating rad 22 so as to be movable up and down.
A nozzle unit 14 is attached to the lower end of the nozzle unit 14, which is provided with two nozzles 15.16 and two stopper pins 17.18.

As shown in FIG. 2, each nozzle 15, 16 for discharging the adhesive 5 has, for example, an outer diameter of 0 in the major axis direction.
．． The 7th cabinet is a cylindrical body with an oval cross-sectional shape and an outer diameter of 0.3 mm in the minor axis direction. They are arranged at intervals such that the distance is, for example, 1.0 km.

The tip of each stopper pin emitter, 18, connects each nozzle 15.
It protrudes downward by a slight length (for example, 0°2 mm) than the tip of the tip.

When applying the adhesive 5 to the printed circuit board 10 using the application device 1, while keeping the storage container 23 at a predetermined height,
The substrate mounting table 21 on which the printed circuit board 10 is placed or the coating head 22 is moved as appropriate, so that both nozzles 15.16 face the gap between the pair of footprints 11.11, as shown in FIG.

That is, the longitudinal direction of the gap between the matte prints 11 and 11 and the longitudinal direction of both nozzles 15 and 16 are made to collapse. In this state, the storage container 23 is lowered until the tips of the stopper bins 17 and 18 come into contact with the surface of the printed circuit board 10, and air pressure is applied to the storage container 23 to dispense a predetermined amount of adhesive 5 from both nozzles 15 and 16. Let it spit out.

As a result, the adhesive 5 is applied to two locations within the gap of the footprint 11.11 so as to swell with the application surface corresponding to the cross-sectional shape of each nozzle 15.16.

After the adhesive 5 has been applied to various application positions, the printed circuit board 10 is sent to a component mounting process.

FIGS. 3(a) and 3(b) are diagrams showing the mounting state of the electronic component 3 according to the present invention. FIG. 3(a) is a cross-sectional front view, and FIG. 3(b) is a plan view, each showing the state after the soldering process using a dip or the like after the component mounting process.

In the component mounting process, the electronic component 3 is mounted on a printed board Fj,1
0 and placed so as to straddle the pair of footprints 11.11. At this time, the applied adhesive 5 is pushed and spread, but the adhesive 5 is applied in two dispersed locations, and as shown in FIG. 3(b), two lumps of adhesive 5 are formed. Since it spreads as if merging, a sufficient adhesive area is obtained on the bottom surface of the electronic component 3 to prevent #I from falling off the electronic component 3, and the footprint of the adhesive 5 is 11.11
No more protruding from the gap.

According to the above-mentioned embodiment, in the production of a component mounting board by SMT, the footprint 1 provided for a microcomponent is
1. It is possible to apply the adhesive 5 in an amount that provides a predetermined adhesive strength to a small width area such as the gap in 11, and soldering caused by the adhesive 5 protruding to the footprint 11 side can result in poor soldering. Occurrence can be prevented. This results in
Soldering can reduce the labor required to inspect for defects and repair work, leading to cost reductions.

In the embodiments described above, the storage container 23 can be made rotatable in a horizontal plane. According to this, it becomes possible to apply the adhesive 5 regardless of the direction in which the fundoblins 11 are arranged.

In the embodiment described above, the dimensions and spacing of the two nozzles 15, 16 can be selected depending on the gap size of the footprints 11, 11.

〔Effect of the invention〕

According to the present invention, it is possible to apply a predetermined amount of adhesive to an application area with a very small width, and it is possible to prevent soldering defects due to the adhesive protruding from the application area.

[Brief explanation of drawings]

Fig. 1 is a front view showing the main parts of the coating device according to the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 (a) and (b) are according to the present invention. FIG. 4 is a perspective view showing a conventional coating device; FIG. 5 is a partially sectional front view showing an enlarged view of the nozzle in FIG. 4; FIG. -Vl line arrow sectional view, Figure 7 (a
) and (b) are diagrams showing the mounting state of conventional electronic components. In the figure, 1 is a coating device, 5 is an adhesive, 15 and 16 are nozzles, and 23 is a storage container. Front views 15 and 16 showing main parts of the coating device according to the present invention.
...Nozzle 5 A cross-sectional view taken along the line nn in FIG. 1. A partial cross-sectional view showing an enlarged view of the nozzle in FIG. 4. A cross-sectional view taken along the line VI-Vl in FIG. 5. Diagram showing the mounting state of parts

Claims (1)

[Claims] (1) In an adhesive applicator (1) configured to discharge a predetermined amount of the adhesive (5) from the lower end of a container (23) containing the adhesive (5), the container (23) ), two nozzles (15) and (16) each having an oval cross-sectional shape are arranged at a distance from each other so that the major diameter direction of each nozzle (15) and (16) is in a straight line; Each nozzle (15), (16
). An adhesive application device characterized in that the adhesive (5) is discharged from a source.