JP2882303B2 - Screen printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing apparatus for printing (supplying) a printing material such as a solder paste or an adhesive on a printed circuit board. The present invention relates to a screen printing apparatus capable of performing good screen printing anywhere on a printed circuit board without any restrictions even when there is a thick protrusion.

[0002]

2. Description of the Related Art In printed circuit boards for electronic circuits, connector parts, ICs,
After mounting thick electronic components such as LSI chips,
Connections between these electronic components and electrodes (hereinafter referred to as “patterns”
Screen printing of a printing material such as a solder paste or an adhesive.

[0003] In screen printing, a screen formed by a mesh or a metal mask is superimposed on a printed circuit board, a printing material is placed on the screen, and then a squeegee is pressed and slid on the screen to make a screen. It refers to a method in which the printing material is extruded from through holes formed at positions corresponding to the pattern, and the printing material is printed on the pattern.

Here, when screen printing is performed on a fine pattern formed on a high-density printed circuit board, a metal mask is exclusively used, and conventionally, electronic components and the like mounted on the printed circuit board have been conventionally used. Various screen printing means have been proposed which can perform good printing while avoiding the projections.

For example, as a first conventional example, Japanese Utility Model Application Laid-open No.
No. 106664 proposes a metal mask for a printed circuit board on which a thin projection is formed. As shown in FIG. 6, the metal mask 110 has a cover 1 having a shape corresponding to the protrusion 121 on the printed circuit board 120.
11 is integrally formed, and the projection 121 is covered with such a cover 111 so that the projection 121 is not pressed against the squeegee 130 during screen printing.
Was protected.

As a second conventional example, Japanese Patent Application Laid-Open No. 3-53
No. 120 proposes a screen printing apparatus for performing screen printing on a printed circuit board on which thick projections are formed.

[0007] As shown in FIG.
Several thick protrusions 211 were mounted on the top 10 in several rows. On the other hand, as shown in FIG.
The metal mask 220 had a rectangular opening 221 corresponding to the row of projections 211. And
As shown in FIGS. 7B and 8, the opening 221 has a bar-shaped cover 230 covering the projection 211 for each row.
Was attached. Further, the squeegee 240 has a comb shape in which a portion corresponding to the cover 230 is cut out.

[0008] Japanese Patent Application Laid-Open No. 3-531 having such a configuration
In the screen printing device of No. 20, the bar-shaped cover portion 23 is used.
0 can prevent the printing material from flowing from the opening 221, and the comb-shaped squeegee 240
The screen printing was able to be performed without the cover unit 230 becoming an obstacle.

[0009]

However, in the above-described conventional screen printing method disclosed in Japanese Utility Model Application Laid-Open No. 63-106664, only the projection 121 having a small thickness is targeted. Therefore, only an improvement of the metal mask 110 is proposed. However, no improvement has been proposed for the squeegee 130, and a conventional squeegee having a flat contact surface with the metal mask 110 is used as it is.

For this reason, the cover portion 111 of the metal mask 110 is formed into a shape corresponding to the thick projection, and screen printing is performed on a printed board having the thick projection. The squeegee 130 that is pressed and slid by cannot get over the protrusion,
There is a problem that screen printing cannot be performed on a printed circuit board having a thick projection.

Further, the above-mentioned conventional Japanese Patent Application Laid-Open No. 3-5312
In the screen printing apparatus of No. 0, the thick projection 21
Since the configuration using the comb-shaped squeegee 240 in which the portion corresponding to No. 1 was cut out was used, the printing material could not be conveyed in the notched portion of the squeegee 240. For this reason, the printing material cannot be supplied to a portion on the straight line where the protrusion 211 of the printed circuit board 210 is provided, and there is a problem that the printable range is limited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. Even when there are thick projections such as electronic components on the surface of a printed circuit board, these projections are not restricted at all. An object of the present invention is to provide a screen printing apparatus capable of performing good screen printing anywhere on a printed circuit board.

[0013]

To achieve the above object, according to an aspect of the screen printing apparatus of the present invention, the printed circuit board having projections on the surface, the solder paste, a screen for a printing material by screen printing, such as an adhesive In the printing apparatus, a metal plate member, which has a cover portion corresponding to the position and shape of the protrusion, and a through hole for transmitting the printing material, and a metal mask formed with guide rails on both sides. A guide portion that moves along a guide rail of the metal mask, and a flexible spatula member having an upper end fixed to the guide portion, and the movable portion smoothly moves in a portion facing the cover portion. Can pass
And the movable part is excessively warped during the passage.
And a squeegee having a movable portion formed with a notch of a high height , wherein the squeegee is higher than the guide rail so that a pressing force is applied to the metal mask during screen printing.

[0014] The screen printing apparatus according to claim 2, there a structure in which the movable part is a large number in the widthwise direction of the squeegee, also, the screen printing apparatus according to the third aspect, the rear surface of the squeegee, the cover In this configuration, a supporter for reinforcing the movable portion at a position not opposed to the portion is attached.

[0015]

According to the screen printing apparatus of the above configuration, when the screen printing is performed by pressing and sliding the squeegee on the metal mask, the movable portion formed on the squeegee becomes the printed board. It comes into contact with the cover that covers the upper protrusion. Thereafter, when the squeegee is further pressed and slid, the movable portion bends and passes over the cover portion while transporting the printing material.

This makes it possible to supply the printing material to the pattern on the straight line of the projections of the printed circuit board. Even if the printed circuit board has thick projections, there is no restriction on these projections. Good screen printing can be performed anywhere on the printed circuit board without receiving.

Further , the height of the squeegee is adjusted by a guide rail.
Height along the guide rails.
When the squeegee is pressed and slid, the
Make screen printing reliably and smoothly with pressure
I can.

According to the screen printing apparatus according to claim 2, wherein, among the plurality of movable portions which is formed in the squeegee, since either of the movable portion corresponding to the cover portion of the metal mask, a single squeegee, Screen printing of various printed circuit boards having different positions of the projections can be performed.

According to the screen printing apparatus of the third aspect, the supporter attached to the back surface of the squeegee reinforces the movable portion at a position not opposed to the cover to reduce the warpage. Thereby, more printing material can be conveyed without leakage at the movable portion at a position not opposed to the cover portion, and screen printing can be performed smoothly.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a screen printing apparatus according to an embodiment of the present invention will be described with reference to the drawings. First, a screen printing apparatus according to a first embodiment will be described. FIG. 1 is a perspective view illustrating a screen printing apparatus according to the present embodiment.

In FIG. 1, reference numeral 1 denotes a printed circuit board,
On its surface, two thick (high) projections 2a and 2b such as connector parts, ICs, LSI chips and the like are provided. In addition, a plurality of patterns 3a, 3b, 3 that are connection portions with the electrodes of the electronic component are provided on the surface of the printed board.
c is formed.

Reference numeral 10 denotes a metal mask, which is formed by a metal plate member. On the surface of the metal mask, two cover portions 11a and 11b having a shape corresponding to the protrusions 2a and 2b of the printed board 1 are formed.
Through holes 12a, 12 respectively corresponding to the plurality of patterns 3.
b, 12c are perforated. Further, a metal mask 10
Guide rails 13, 13 facing each other are attached to both ends.

Reference numeral 20 denotes a squeegee, which is a flexible rectangular spatula member. A cut 21 is made in the height direction in a portion of the squeegee 20 facing the cover portions 11a and 11b, so that the two movable portions 22a and
22b are formed. These movable parts 22a, 22b
Has a width capable of smoothly passing through the cover portions 11a and 11b, and the movable portion 22
It is assumed that the heights a and 22b are not excessively curved.

At the upper end of the squeegee 20, a plate-like guide portion 23 corresponding to the guide rail 13 of the metal mask 10 is attached. The height of the squeegee 20 is slightly higher than the height of the guide rail 13. When the guide portion 23 is pressed against the guide rail 13, the squeegee 20 bends and an appropriate pressing force is applied to the metal mask 10. It is like that.

Next, the printing operation of the screen printing apparatus of the first embodiment having the above configuration will be described with reference to FIGS.
Description will be made with reference to (a), (b), and (c). FIG.
(A)-(b) is an explanatory view showing a series of printing operation of this screen printing device.

In FIG. 1, when performing screen printing, first, a metal mask 10 is superimposed on the printed circuit board 1 such that each cover portion 11 corresponds to each projection portion 2. Then, a printing material 30 such as a solder paste or an adhesive is placed near one end of the metal mask 10, and the guide portion 23 is pressed against the guide rail 13, and the one end of the metal mask 10 is pressed. The squeegee 20 is arranged at the position.

Next, the squeegee 20 is placed on the metal mask 10.
When pressed and slid in the direction of arrow A in FIG.
The printing material 30 is conveyed in the direction A by 0, and the printing material 30 is printed on the pattern 3a of the printed board 1 by the entire squeegee 20 passing over the through holes 12a of the metal mask 10.

When the squeegee 20 is further pressed and slid in the direction A, as shown in FIG.
0 is close to each of the cover portions 11a and 11b.
As shown in (b), each movable part 22a,
22b is in contact with each cover 11a, 11b. Then, each of the movable portions 22a and 22b bends in the direction opposite to the direction A, and while the printing material 30 is conveyed, each of the cover portions 11
Get over a, 11b.

At this time, portions other than the movable portions 22a and 22b of the squeegee 20 pass over the through holes 12b, and the printing material 30 is printed on the pattern 3b (see FIG. 1).

Thereafter, as shown in FIG. 2 (c), each movable part 22a, 22 which has passed over each cover part 11a, 11b
b returns to the original state, and the printing material 30 is imprinted on the pattern 3c by the entire squeegee 20 passing over the through hole 12c.

According to the screen printing apparatus of the first embodiment having such a configuration, each cover 1 of the squeegee 20
Movable parts 22a, 22b are provided at portions facing 1a, 11b.
Is formed, the printing material 30 can be supplied to the pattern 3c which is on the straight line of the projections 2a and 2b, and is not restricted by these projections 2a and 2b at any place on the printed circuit board 1. Good screen printing can be performed.

The notch 21 allows the movable portion 22
a, 22b, each movable part 22a, 22b
When b moves over the cover portions 11a and 11b, the printing material 30 does not leak from the sides of the movable portions 22a and 22b, and sufficient printing material 30 to be supplied to the pattern 3c is supplied to the movable portions 22a and 11b. , 22b.

Furthermore, according to the screen printing apparatus of the first embodiment, the squeegee 20 is moved with a constant height and a constant force by pressing and sliding the squeegee 20 along the guide rail 13. Screen printing can be performed more smoothly.

Next, a screen printing apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 7 is a perspective view illustrating a squeegee of the screen printing apparatus according to the second embodiment.

The screen printing apparatus according to the present embodiment has a configuration in which a number of movable parts 41 are formed in the width direction of the squeegee 40. According to such a configuration, a large number of movable portions 41
Of these, any one of the movable portions 41 corresponds to the cover portion of the metal mask, so that a single squeegee 40 can perform screen printing on various printed circuit boards having different projection positions.

Next, a screen printing apparatus according to a third embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 8 is a rear perspective view showing a squeegee of the screen printing apparatus according to the fourth embodiment.

The screen printing apparatus according to this embodiment includes movable portions 41a, 41b, 41 facing the cover portion of the metal mask on the back surface of the squeegee 40 in the second embodiment.
The supporter 42 for reinforcing the movable parts 41d, 41e, 41f, 41g other than c is attached.

According to such a configuration, the supporter 52
Are movable portions 41d to 4d at positions not opposed to the cover portion.
Since 1 g is reinforced to reduce the warpage, these movable portions 41 d to 41 g can be brought into strong contact with the metal screen 10. Thereby, the movable parts 41d to 41d
With g, more printing material can be conveyed without leakage, and screen printing can be performed more smoothly.

The screen printing apparatus according to the present invention is not limited to the first to third embodiments. In the above embodiment, as shown in FIG.
b is formed integrally with the metal mask 10, but this is not particularly limited, and each cover portion 11a,
11b may be configured to be independent and independent of the metal mask 10.

Further, in the above embodiment, as shown in FIG. 2, the outer shape of each of the cover portions 11a and 11b is a rectangular parallelepiped formed of a plane, but this is not particularly limited. It may be a curved surface as shown in FIG.
In the case of such a configuration, each of the movable parts 22a, 22b
However, it is possible to get over each cover part more smoothly.

[0041]

As described above, according to the screen printing apparatus of the present invention, since the movable portion is formed by making a cut in the squeegee, a thick projection such as an electronic component is formed on the surface of the printed circuit board. Even if there is an object, good screen printing can be performed anywhere on the printed circuit board without any restrictions on these projections.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a screen printing apparatus according to an embodiment of the present invention.

FIGS. 2A to 2C are explanatory diagrams showing a series of printing operations of the screen printing apparatus.

FIG. 3 is a perspective view showing a squeegee of a screen printing apparatus according to a second embodiment of the present invention.

FIG. 4 is a rear perspective view showing a squeegee of the screen printing apparatus according to the third embodiment of the present invention.

FIG. 5 is a side view showing a modified example of the screen printing apparatus according to the embodiment.

FIG. 6 is a partial sectional side view showing a screen printing apparatus according to a first conventional example.

7A and 7B show a screen printing apparatus according to a second conventional example, wherein FIG. 7A is a perspective view showing a printed circuit board to be subjected to screen printing, and FIG. 7B is a partial cross-sectional side view. .

FIG. 8 is a perspective view showing a screen printing apparatus according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2a, 2b Projection part 3a, 3b, 3c Pattern 10 Metal mask 11a, 11b Cover part 12a, 12b, 12c Through hole 13 Guide rail 20, 40 Squeegee 21 Cut 22a, 22b, 41 41a-41g Movable part 23 Guide Part 30 Printing materials 52 Supporters

Claims (3)

(57) [Claims] 1. A screen printing apparatus for screen-printing a printing material such as a solder paste or an adhesive on a printed circuit board having projections on its surface, the screen printing apparatus comprising: a metal plate member; And a metal mask having a guide hole formed on both sides while having a through-hole for transmitting the printing material, a guide portion moving along the guide rail of the metal mask, and the guide portion Is a flexible spatula member having an upper end fixed thereto, and a portion facing the cover portion.
The width is such that the movable part can pass smoothly and
And a squeegee in which the movable portion is formed with a notch having a height that does not warp excessively so as to form a movable portion.The squeegee is higher than the guide rail so that a pressing force is applied to the metal mask during screen printing. A screen printing apparatus characterized by the above-mentioned. 2. The screen printing apparatus according to claim 1, wherein a number of said movable portions are formed in a width direction of said squeegee. 3. The screen printing apparatus according to claim 1, wherein a support for reinforcing a movable portion at a position not opposed to the cover is attached to a back surface of the squeegee.