JP2003094613A - Printing solder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing solder device capable of suppressing and reducing a shifted amount of a substrate on the whole. SOLUTION: In the printing solder device which print creamy solder 8 on a substrate 4 through a metal mask 1 having opening parts 2 through which the solder 8 passes, positioning marks 2-1 to 2-8 and 5-1 to 5-8 are attached to the positions of eight points which are mutually opposed to each other one the metal mask 1 and the substrate 4 and respective marking positions are recognized with a position recognizing camera 7 to make the position adjustment of the metal mask 1 and the substrate 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention prints solder on a printed wiring board (hereinafter abbreviated as a board) made of ceramic or the like for mounting electronic parts such as chip parts and winding parts. The present invention relates to a solder printing device.

[0002]

2. Description of the Related Art A two-point position recognition printing device has been commercialized as a solder printing device for printing creamy solder on a substrate through a printing screen having an opening through which the solder passes like a metal mask. A four-point position recognition printing device has also been proposed. In this method, the printing screen and the board are aligned at two or four points with marks, and then solder printing is performed.

FIG. 3 is a perspective view showing a first example of a two-point position recognition mechanism. As shown in the figure, two alignment marks 3-1 and 3-2 are provided on the periphery of the metal mask 1, and two alignment marks 6-1 and 6-2 are provided on the periphery of the substrate 4.
Are formed respectively. The metal mask 1 and the substrate 4 are opposed to each other with a predetermined gap, and the alignment marks (3-1, 3-2 and 6-1, 6-2) of the respective position alignment cameras 7-1, 7-. 2 and the position alignment marks 3-1 and 6- based on the recognized position information.
1 and the positions where the positional deviation amounts of the alignment marks 3-2 and 6-2 become smaller are calculated.

Then, the metal mask 1 or the substrate 4 is moved to that position in the vertical direction and / or the horizontal direction in the figure, and thereafter, the metal mask 1 and the substrate 4 are placed in a superposed state, and the solder on the metal mask 1 is placed. (Not shown) is passed through the openings 2 (basically a plurality), and printed on the component land 5 (basically corresponding to the openings 2) on the substrate 4.

When there is only one position recognition camera, the structure is such that it can move to the respective positions 7-1 and 7-2. In the case of a printing apparatus having two position recognition cameras, the position recognition cameras 7-1 and 7 are installed.
-2 can be moved to the position shown in the figure.

FIG. 3 shows the alignment marks 3-1 and 3-.
2, 6-1 and 6-2 show an example in which they are provided at positions other than the component land 5 which is the print target of soldering. In this example, as a result, the position where the registration position shift amount of the alignment marks 3-1 and 6-1 and the alignment marks 3-2 and 6-2 is minimum is the alignment mark 3-1.
And a line segment a-1 that connects the two points 3-2 and a line segment b-1 that connects the two points of the alignment marks 6-1 and 6-2 are overlapped with each other. The position is such that the amount of deviation between 6-1 and the amount of deviation between the alignment marks 3-2 and 6-2 are the same.

FIG. 4 is a perspective view showing a second example of the two-point position recognition mechanism. In this example, as shown in FIG. 3, the special alignment marks 3 and 6 are not provided, and as the alignment marks, the openings 2-1 and 2-2 of the metal mask 1 and the component land 5-1 corresponding to these are formed. 5-2 is used. In this case, a line segment connecting the two points of the openings 2-1 and 2-2 is a-2, and a line segment connecting the two points of the component lands 5-1 and 5-2 is b-2.

In the example shown in FIGS. 3 and 4, the solder printing on the substrate 4 is shown in FIGS. 5 and 6, respectively. The reference numeral 8 indicated by hatching in both figures is the metal mask 1
Represents the solder printed on the substrate 4 through the opening 2 in FIG.
Further, the maximum displacement of the solder 8 with respect to the component land 5 in the X direction (horizontal direction in the drawing) is X-1, X-2,
Set the maximum misalignment part in the Y direction (vertical direction in the figure) to Y-
1 and Y-2, in the two-point position recognition method, the solder 8 is positioned so that the displacement amount in the vicinity of the alignment mark is relatively small.
A portion with a large displacement occurs such as 1, Y-1. This tendency becomes more remarkable as the positional displacement of the component land 5 due to the contraction deformation of the substrate 4 increases.

FIG. 7 is a perspective view showing an example of a four-point position recognition mechanism. The openings 2-1 to 2-4 of the metal mask 1 and the component lands 5-1 to 5-4 of the substrate 4 are used as alignment marks. The position recognition camera 7-1,
7-2, and based on the recognized position information, the position where the amount of positional deviation of the alignment marks 2-1 to 2-4 and the alignment marks 5-1 to 5-4 becomes small is calculated.

Then, the metal mask 1 or the substrate 4 is moved to that position in the vertical direction and / or the horizontal direction in the figure, and after that, the metal mask 1 and the substrate 4 are placed in a superposed state, and the solder on the metal mask 1 is placed. (Not shown) is passed through the openings 2 (basically a plurality), and printed on the component land 5 (basically corresponding to the openings 2) on the substrate 4.

When there is only one position recognition camera, the structure is such that it can be moved to the positions indicated by reference numerals 7-1 and 7-2. In the case of a printing apparatus having two position recognition cameras, the position recognition cameras 7-1 and 7-
2 is movable to the position shown in the figure.

FIG. 8 shows a state in which solder printing is performed on the substrate 4 in the example shown in FIG. Reference numeral 8 shown by hatching in FIG. 8 indicates solder printed on the substrate 4 through the opening 2 of the metal mask 1. Further, the maximum displacement of the solder 8 with respect to the component land 5 in the X direction (horizontal direction in the drawing) is defined as X-3, and the Y direction (vertical direction in the drawing).
If the maximum position deviation part of the above is set to Y-3, even in the four-point position recognition method, the amount of deviation of the solder 8 in the vicinity of the alignment mark is positioned so as to be relatively small. 3 and Y-3, a portion with a large displacement occurs. This tendency becomes more remarkable as the positional displacement of the component land 5 due to the contraction deformation of the substrate 4 increases.

[0013]

As described above, although the conventional two-point alignment mechanism and four-point alignment mechanism can reduce the amount of positional deviation in the vicinity of the alignment mark, when viewed from the entire substrate, The amount of displacement is not necessarily small. Depending on the degree of deformation of the substrate and the like, it is possible that the amount of misalignment is sufficiently increased at the portion deviated from the alignment mark. In particular, since the ceramic substrate has a large variation in shrinkage deformation amount due to sintering, the above-mentioned tendency is remarkable.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a solder printing apparatus having high printing reliability, which can suppress and reduce the amount of misalignment of the entire substrate. .

[0015]

In order to achieve the above-mentioned object, the first means of the present invention is to print creamy solder on a printed wiring board through a printing screen having openings through which the solder passes. In the solder printing apparatus, the printing screen and the printed wiring board are opposed to each other.
Positions above the point are used as alignment marks, and the mark recognition means recognizes each mark position to align the print screen and the printed wiring board.

According to a second aspect of the present invention, in the first means, the printing screen is a metal mask and the mark recognizing means is a camera.

In a third means of the present invention according to the second means, one or a plurality of the cameras can be moved to respective mark positions between the printing screen and the printed wiring board during alignment. It is characterized by that.

As described above, according to the present invention, when aligning the substrate with respect to the printing screen, five or more arbitrary positions corresponding to the printing screen and the substrate are recognized by a camera or the like, and the printing screen is determined based on the positional information. The position of the printing screen or the substrate is determined and alignment is performed so as to reduce the positional deviation from the substrate.

In other words, the number of position recognition points between the printing screen and the substrate is increased so that the tendency of the positional deviation of the entire substrate can be seen, and the correction amount for reducing the positional deviation between the printing screen and the substrate from the positional deviation amount. By determining (X, Y, θ directions; up, down, left and right, rotation direction), the position of the printing screen or the substrate is corrected and controlled for alignment.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of an 8-point position recognition mechanism in a solder printing apparatus according to an embodiment.
The openings 2-1 to 2-8 of the metal mask 1 and the component lands 5-1 to 5-8 of the substrate 4 are used as alignment marks. Then, this is recognized by the position recognition cameras 7-1 to 7-8, and based on the recognized position information, the alignment marks 2-1 to 2-8 and the alignment marks 5-1 to 5-1.
The position where the amount of positional deviation of 5-8 becomes small is calculated.

Then, the metal mask 1 or the substrate 4 is moved to that position in the vertical direction or (and) the horizontal direction or (and) the rotating direction of the figure, and thereafter, the metal mask 1 and the substrate 4 are placed in a superposed state. Printing solder (not shown) on the metal mask 1 through the openings 2 (basically a plurality) and on the component land 5 on the substrate 4 (basically corresponding to the openings 2) To do.

When there is only one position recognition camera, the structure is such that it can move to each of the positions 7-1 to 7-8. Further, in the case of a printing apparatus in which eight position recognition cameras are installed, each position recognition camera 7-1 to 7-
8 is movable to the position shown in the figure.

FIG. 2 shows a state in which solder printing is performed on the substrate 4 in the example shown in FIG. Reference numeral 8 indicated by hatching in FIG. 2 represents solder printed on the substrate 4 through the opening 2 of the metal mask 1. Further, the maximum displacement of the solder 8 with respect to the component land 5 in the X direction (horizontal direction in the drawing) is defined as X-4, and the Y direction (vertical direction in the drawing).
The maximum displacement amount of the portion is Y-4, and the maximum displacement amount in that portion is the maximum displacement portion X- shown in FIGS.
It can be seen that the amount of positional deviation in the present invention is small when compared with the amount of positional deviation in 1, Y-1, X-2, and Y-2. Therefore, when viewed from the entire substrate 4, the maximum displacement amount is reduced as compared with the conventional example.

[0024]

The present invention is constructed as described above, and increases the number of position recognition points between the printing screen and the substrate,
A correction amount (X, Y, θ directions; up and down, so as to reduce the positional deviation between the printing screen and the substrate from the positional deviation amounts).
The position of the printing screen or the board is corrected and controlled to determine the position, and the position of the printing screen or the board is adjusted, so that the amount of solder printing deviation with respect to the board can be reduced. This has the following effects. (1) Component mounting defects after solder printing are reduced. (2) Floating parts, standing parts in reflow after mounting parts,
Defects such as solder flow to adjacent component lands are reduced. (3) Rework work associated with the above defects is reduced. (4) Due to the above (1) to (3), the efficiency of the assembly work is improved and the productivity is improved. (5) Since the amount of positional deviation is small, the distance between component lands can be shortened as compared with the conventional case. As a result, when considering the mounting of the same component, it is possible to further reduce the board size compared to the conventional one, and the product value as a board component increases.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an 8-point printing recognition mechanism in a solder printing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view for explaining a solder printing condition on a substrate according to the present embodiment of FIG.

FIG. 3 is a perspective view showing a first example of a two-point position recognition mechanism.

FIG. 4 is a perspective view showing a second example of a two-point position recognition mechanism.

5 is a plan view for explaining a solder printing condition on a substrate according to the example of FIG. 3;

6 is a plan view for explaining a solder printing condition on a substrate according to the example of FIG. 4;

FIG. 7 is a perspective view showing an example of a four-point position recognition mechanism.

8 is a plan view for explaining a solder printing condition on a substrate according to the example of FIG. 7. FIG.

[Explanation of symbols]

1 metal mask 2 openings 3 Mask side alignment mark 4 substrates 5 parts land 6 PCB alignment mark 7 Position recognition camera 8 Solder printed on the board

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinya Yoshida             No. 1 Kitano, Majo, Mizushiro City, Iwate Prefecture             Within Hitachi Media Electronics (72) Inventor Inao Abe             Hitachi-te, 5-2 Koyodai, Ryugasaki City, Ibaraki Prefecture             Within Kuno Engineering Co., Ltd. F-term (reference) 2C035 AA06 FB26 FB39                 2C250 EA37 EB25 EB26 EB29                 5E319 AA03 BB05 CD29 GG03 GG15

Claims (3)

[Claims] 1. A solder printing apparatus for printing a cream-like solder on a printed wiring board through a printing screen having an opening through which the solder passes, wherein at least five points of the printing screen and the printed wiring board facing each other are provided. A solder printing apparatus, wherein each position is used as an alignment mark, and the mark recognition means recognizes each mark position to align the print screen and the printed wiring board. 2. The solder printing apparatus according to claim 1,
The solder printing apparatus, wherein the printing screen is a metal mask, and the mark recognition means is a camera. 3. The solder printing apparatus according to claim 2,
A solder printing apparatus comprising one or a plurality of the cameras, which can be moved to respective mark positions between a printing screen and a printed wiring board during alignment.