JPH0417105B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an adhesive applicator, in which a lowering limit of the applicator pin is defined at the center of the lower surface of the applicator pin,
In addition, a protrusion is provided to cause the adhesive to become stringy.

(Prior Art) As a means for attaching electronic components to a board, a method is known in which an adhesive is applied in advance to a predetermined position on the board, and then the electronic component is mounted on the adhesive.
Means for applying adhesive to a substrate are roughly divided into a transfer method in which the adhesive in a container is transferred to the substrate using a coating pin, and a discharge method in which the adhesive is discharged from a dispenser and applied to the substrate.

FIG. 8 shows an adhesive transfer operation using a conventional applicator pin. As shown in Figure a, the applicator pin 12 is lowered and immersed in the adhesive 13 stored in the container 3, and then as shown in Figure b, the applicator pin 12 is raised.
Adhere the adhesive 13 to the bottom surface of 2, and then
The adhesive 13 is transferred to the substrate 5 by landing the applicator pin 12 on the substrate 5 as shown in FIG. Next, as shown in the same figure e, this adhesive 1
Electronic components 6 are mounted on 3.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional means, as shown in FIG. When the liquid surface of the adhesive 13 is suddenly hit, the adhesive 13 is scattered, and as shown in FIG.
As the adhesive 13 has a high viscosity, the surface of the adhesive 13 inside the container 3 and the adhesive 13 attached to the bottom surface of the pin 12 becomes rough and fluffy, causing the bottom surface of the pin 12 to become rough. The adhesion distribution and amount of adhesive 13 adhering to the substrate 5 were not constant, and as a result, the amount of adhesive 13 applied to the substrate 5 was likely to vary.

Furthermore, as shown in FIG. 3c, when transferring the adhesive 13 of the applicator pin 12 onto the substrate 5, the lowering limit of the applicator pin 12 is not determined, so that the downward stroke of the applicator pin 12 becomes excessive and the adhesive 13 is transferred to the substrate 5. The surface of the adhesive 13 tends to bulge out to the sides, and as shown in Figure d, when the applicator pin 12 rises, the surface of the adhesive 13 becomes rough and fluffy due to the same reason as in Figure b. The adhesive 13 was difficult to be sufficiently transferred to the substrate 5.

In addition, as shown in FIG.
Since the surface of the electronic component 6 is rough, there is a problem in that air is easily trapped in the lower surface of the electronic component 6 and air bubbles 10 are easily generated. When the bubbles 10 are generated, the bubbles 10 undergo thermal expansion due to the heat generated when the adhesive 13 is heated and cured, and due to the self-heating of the electronic components 6 when the electronic components 6 are incorporated into electrical equipment and driven. This may cause damage to the electronic components 6.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an adhesive coating device that can solve the problems of the conventional means described above.

(Means for Solving the Problems) For this purpose, in the present invention, a protrusion that lands on the bottom of a container in which adhesive is stored is provided protruding from the center of the lower surface of the applicator pin.

(Function) In the above configuration, when the applicator pin moves toward the adhesive in the container and descends, the protrusion first immerses into the adhesive, then the applicator pin gently immerses into the adhesive,
The protrusion then lands on the bottom of the container. The applicator pin then rises, but in this case, the adhesive is threaded onto the protrusions, so the surface of the adhesive is not roughened, and the adhesive adheres to the lower surface of the applicator pin in a uniform thickness.

Next, the adhesive adhered to the applicator pin is transferred to the substrate, but in this case, the downward limit of the applicator pin is defined by the protrusion landing on the substrate, and almost no adhesive bulges out to the side. Furthermore, when the applicator pin rises, threading occurs on the protrusion, so the adhesive is transferred to the board in a good shape, approximately in the shape of a mountain. Therefore, the electronic components are landed on this adhesive and mounted. When doing so, air will not be drawn in and bubbles will not be created.

(Example) Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an overall perspective view of the die bonder. Reference numeral 1 denotes a transfer device, which has an adhesive application head 2 and a transfer head 7. An adhesive supply device 3a is provided below the coating head 2 and includes a container 3 in which adhesive 13 is stored. 5 is a printed circuit board, which is held and positioned by a board holder 4 on an XY table that moves in the XY directions. 8
is an electronic component positioning device. Transfer head 7
The electronic component 6 on the electronic component positioning device 8 is transferred onto the printed circuit board 5 positioned on the board holder 4. Further, the coating head 2 applies the adhesive in the container 3 to the printed circuit board 5.

The coating head 2 has a coating pin 12a shown in FIG.
have. A protrusion 15 projects from the center of the lower surface of the applicator pin 12a. Depending on the size of the electronic component 6, the size of the applicator pin 12a and the protrusion 15 may vary.
By changing the height 14 of the applicator pin 12a,
The desired amount of adhesive is applied to the printed circuit board 5 by adjusting the amount of adhesive attached to the lower surface of the printed circuit board 5. Next, the operation will be explained.

As shown in FIG. 3a, the applicator pin 12a is lowered and immersed in the adhesive 13 of the container 3. Next, when the applicator pin 12a is raised, the adhesive 13 adheres to the lower surface of the applicator pin 12a (FIG. 3b). Next, this application pin 12a is landed on the substrate 5 (third
c), then by lifting the adhesive 13 is transferred to the substrate 5 (Fig. 3d). Next, the electronic component 6 is lowered onto this adhesive 13 (e in the same figure),
The electronic component 6 is mounted on the adhesive 13 (f in the same figure).

As shown in FIG. 3a, when the applicator pin 12a is immersed in the adhesive 13, the protrusion 15 is immersed first, so the lower surface of the applicator pin 12a suddenly hits the liquid surface of the adhesive 13 strongly, causing the adhesive 13 to immerse. The applicator pin 12a can be quietly immersed into the adhesive 13 without being scattered laterally. Moreover, since the lowering limit of the applicator pin 12a is determined by the projection 15 landing on the bottom surface 19 of the container 3, the applicator pin 12a can be immersed into the adhesive 13 to a desired depth. Incidentally, in Figure 3 a,
The adhesive 13 in the container 3 adheres to the applicator pin 12a at a hatched portion A directly below the applicator pin 12a. Therefore, by changing the height of the protrusion 15 and adjusting the immersion depth of the applicator pin 12a, the amount of adhesive 13 deposited can be adjusted.

Further, as shown in FIG. 3b, when the applicator pin 12a is raised, strings of the adhesive 13 are generated on the protrusion 15. Therefore, as shown in the conventional means shown in FIG.
The surface of the adhesive 13 does not become fluffy or rough, and an approximately predetermined amount of the adhesive 13 can be applied to the lower surface of the applicator pin 12a with an approximately uniform thickness.

Also, when the adhesive 13 is transferred to the substrate 5, as shown in FIG. 3c, the downward limit of the applicator pin 12a is defined by the protrusion 15 landing on the substrate 5, and as shown in FIG. , the applicator pin 12a
When the adhesive 13 rises, strings A are generated from the protrusions 15, so that the surface a of the adhesive 13 transferred to the substrate 5 has a protruding residue of the strings A protruding in the center, as shown in Figure e. The surface a has a substantially mountain-like shape, and the surface a is smooth with no fluff.

Therefore, as shown in figure e, this adhesive 1
When mounting the electronic component 6 on the electronic component 3, the bottom surface of the electronic component 6 first lands on the residue A, and then crushes this residue A and spreads it around while the entire bottom surface lands on the adhesive 13. The electronic component 6 can be satisfactorily adhered to the adhesive 13 without causing air bubbles to be generated under the electronic component 6.

By changing the size of the applicator pin 12a and the height of the protrusion 15, the amount of adhesive 13 that adheres to the applicator pin 12a can be changed, and as shown in FIG. It is also possible to prevent the adhesive 13a from protruding slightly from the corners, or to prevent the adhesive 13b from protruding from the electronic component 6, as shown in FIG.

By the way, when the dimensions of the electronic component 6 are large, as shown in FIG. It may not be possible. Therefore, in such a case, if a protrusion 15 and a groove 16 are formed on the applicator pin 12b as shown in FIG. 6, so that the adhesive adheres to the X-shaped adhesion surface 18, as shown in FIG. The adhesive 13d is applied to almost the entire lower surface of the electronic component 6 including the corners, so that the electronic component 6 can be reliably bonded.

(Effects of the Invention) As explained above, in the present invention, the protrusion that lands on the bottom surface of the container is provided in a protruding manner at the center of the lower surface of the applicator pin, so that the following effects can be obtained.

(1) The protrusion will be immersed into the surface of the adhesive in the container, and then the applicator pin will be immersed into the adhesive, so carefully immerse the applicator pin into the adhesive without suddenly hitting the liquid surface with the applicator pin. can be done.

(2) When the applicator pin rises, strings are generated from the protrusions, so the surface of the adhesive does not become fluffy and rough, and the desired amount of adhesive can be deposited on the underside of the applicator pin. .

(3) The descent limit of the applicator pin is determined by the projection landing on the board, which eliminates the sideward bulge of adhesive that occurs when the applicator pin descends excessively and is pressed against the printed circuit board. can.

(4) When the applicator pin rises from the board, threading occurs from the protrusion, so the surface of the adhesive transferred to the board does not fluff and is transferred well, reducing the amount of adhesive applied to the printed board. becomes stable.

(5) The central part of the adhesive transferred to the board will be slightly higher due to the residue of stringing, and there will be no fuzz on the surface of the adhesive, so when mounting electronic components, there is no need to entrain air. , electronic components can be well bonded to the adhesive without generating bubbles.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention.
The figure is an overall perspective view of the die bonder, Figure 2 A and B are side and bottom views of the applicator pin, and Figure 3 a, b, c,
d, e, f are side views in the order of operation, Figure 4 A and B are plan views of the adhesive and electronic components, Figure 5 is the same plan view, and Figure 6 A and B are applicator pins of other embodiments. 7 is a plan view of the adhesive and electronic components, and FIGS. 8a, b, c, d, and e are side views of the conventional means in the order of operation. 3...Container, 5...Substrate, 12a...Applying pin, 13...Adhesive, 15...Protrusion.

Claims (1)

[Claims] 1. Equipped with a container in which adhesive is stored and an adhesive applicator pin, the applicator pin is immersed in the adhesive to adhere the adhesive to the lower surface of the adhesive, and the applicator pin is allowed to land on the substrate. An adhesive applicator for transferring the adhesive onto a substrate, characterized in that a protrusion that lands on the bottom surface of the container is provided in a protruding central portion of the lower surface of the applicator pin.