JPH05237987A - Screen printing machine - Google Patents

Abstract

PURPOSE:To enable accurate printing even when a screen having a seamless pattern formed thereon is used while easily enabling the alignment of a substrate 5 with the screen. CONSTITUTION:A substrate 5 and the central part 2b and outer peripheral part 2c of a screen 2 are simultaneously positioned by the positioning pins 26, 27 vertically provided on a base stand 7, and the central part 2b is held by an upper electromagnet 28 and the screen 2 after positioning is attracted by a lower electromagnet 24 to perform screen printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen printing machine for printing a paste such as cream solder on a member to be printed such as a substrate, and particularly screen printing capable of printing using a screen having a seamless pattern. Regarding the machine.

[0002]

2. Description of the Related Art FIG. 5 shows the configuration of an example of a conventional screen printing machine. In FIG. 5, a screen 2 is mounted on the screen mounting base 1, and both ends of the screen 2 are positioned by a stopper 3 and a positioning screw 4 provided on the screen mounting base 1, respectively. A rectangular opening 1a is formed in the center of the screen mount 1, and a pair of substrate guides 6 on which a substrate 5 as a member to be printed is mounted are provided in the opening 1a. A base 7 is provided below the substrate 5 mounted on the substrate guide 6 so as to be able to move up and down. By raising the base 7, the substrate 5 is brought into close contact with the screen 2. Then, the squeegee 9 fixed to the holder 8 is moved in the direction of arrow A, and the paste 10 on the screen 2 is printed on the substrate 5 via the screen 2.

[0003]

However, in the conventional screen printer constructed as described above, a pair of alignment holes 11 are provided in the screen 2 and the substrate 5 as shown in FIG. Therefore, when the screen 2 and the substrate 5 are mounted on the screen mounting base 1 and the base 7, respectively, it is necessary to insert positioning pins (not shown) into the holes 11 to perform accurate alignment.

When an annular pattern 2a as shown in FIG. 7 is formed on the screen 2, there is no seam connecting the inside and outside of the pattern 2a, so that the central portion 2b cannot be supported. However, it was impossible to perform positioning and accurate printing.

The present invention has been made in view of the above circumstances, and it is possible to easily align the member to be printed and the screen with each other, and to use a screen having a seamless pattern formed thereon, which is accurate. An object of the present invention is to provide a screen printing machine capable of excellent printing.

[0006]

A screen printing machine according to the present invention has a substrate 5 mounted on a base 7 as a member to be printed.
In a screen printing machine that prints the paste 10 on the screen 2 through the screen 2, positioning pins 26 and 27 as positioning means that stand upright on the base 7 and position the substrate 5 and the screen 2 at the same time, and move up and down on the base 7. It is characterized by having a pair of upper and lower electromagnets 24 and 28 that are freely supported and adsorb the screen 2.

[0007]

In the screen printing machine having the above structure, the screen 2a and the substrate 5 are simultaneously positioned relative to each other by the positioning pins 26 and 27 provided upright on the base 7. Precise alignment is not required when the is first installed in the screen printing machine.

Even if the screen 2 is formed with, for example, a ring-shaped pattern 2 and there is no seam connecting the inside and the outside of the pattern 2a, the central portion 2b and the outer peripheral portion 2c are positioned independently of each other. Highly accurate printing can be performed. In this case, since the central portion 2b of the screen 2 is held by the upper electromagnet 28 before printing and is held by the lower electromagnet 24 during printing, the positioning pins 26 and 27 can be separated from the screen 2 and the substrate 5 during printing. Yes, printing is possible.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the screen printing machine of the present invention will be described below with reference to the drawings.

1 to 3 show the configuration of an embodiment of the present invention. In these figures, parts corresponding to those of the conventional example shown in FIGS. 5 to 7 are designated by the same reference numerals, and the description thereof will be omitted as appropriate. An annular pattern 2a is formed on the metallic screen 2 used in this embodiment as shown in FIG. 2, and three positioning holes 21 are formed in the central portion 2b.
However, the outer peripheral portion 2c is provided with four positioning holes 22. The substrate 5 described below is also provided with positioning holes 5a and 5b at positions aligned with the holes 21 and 22, respectively.

As shown in FIG. 1, the base 7 has a drive shaft 23.
The lower electromagnet 24 is attached via a drive source (not shown) so as to be vertically movable. The base 7 is the drive shaft 2
It is driven up and down via a drive source (not shown) via 5. Positioning pins 26 and 27 are erected on the upper surface of the base 7 at positions aligned with the positioning holes 21 and 22 shown in FIG. 2, respectively, so that they can penetrate through the lower electromagnet 24 and project upward. There is. Further, the positioning pins 26 and 27 are tapered at their tips as shown in FIG. Further, an upper electromagnet 28 is provided on the upper part of the base 7 so as to face the positioning pin 26, and can be moved vertically by a drive source (not shown) via a drive shaft 29. Also, the upper electromagnet 28
Pin escape holes 28a are formed at positions on the lower surface facing the positioning pins 26, respectively.

Next, the operation of this embodiment will be described with reference to FIGS. FIG. 1 shows a state before the substrate 3 is supplied, and the outer peripheral portion 2c of the screen 2 shown in FIG. 2 is placed on the screen mounting base 1 at a substantially predetermined position. Further, the central portion 2b of the screen 2 is turned on and the upper electromagnet 28 is turned on.
Is adsorbed at a substantially predetermined position, and is located above the screen mounting base 1 together with the upper electromagnet 28. At this time, the base 7 is descending together with the lower electromagnet 24,
The lower electromagnet 24 is off.

Next, as shown in FIG. 4A, the substrate 5 is inserted along the substrate guide 6 and placed at a substantially predetermined position. Next, as shown in FIG. 4B, the base 7 is attached to the lower electromagnet 2
4 through the drive shaft 25 and the positioning pin 2
6 and 27 are fitted into positioning holes 5a and 5b respectively formed at predetermined positions of the substrate 5. The substrate 5 thus positioned rises to the lower surface of the outer peripheral portion 2c of the screen 2, and then the lower electromagnet 24 is turned on. Next, the upper electromagnet 28 descends together with the central portion 2b of the screen 2, and the upper electromagnet 28 is turned off immediately before the central portion 2b contacts the upper end of the positioning pin 26. As a result, the central portion 2b of the screen 2 is attracted to the lower electromagnet 24, the positioning pin 26 is fitted and positioned in the positioning hole 21 formed in the central portion 2b, and is brought into close contact with the substrate 5.

Next, as shown in FIG. 4 (c), after raising the upper electromagnet 28 in the OFF state, only the base 7 is lowered while the lower electromagnet 24 is in the ON state. In this state, the screens 2b and 2c are both positioned and fixed to the substrate 5 by the upper electromagnet 24. Then, the squeegee 9 fixed to the holder 8 is moved in the direction of arrow A, and the screen 2
The upper paste 10 is printed on the substrate 5 through the screen 2.

Next, as shown in FIG. 4 (d), when printing is completed, the upper electromagnet 28 descends, contacts the central portion 2b of the screen 2, and then the upper electromagnet 28 is turned on. After that, the lower electromagnet 24 is turned off, and in this state, the lower electromagnet 24 descends onto the base 7. At this time, the substrate 5 is locked by the substrate guide 6 and conveyed to the next step. Then, the upper electromagnet 28 ascends with the central portion 2b adsorbed and returns to the state shown in FIG.

According to this embodiment, the positioning holes 2 formed at predetermined positions on the screen 2 and the substrate 5, respectively.
Common positioning pins 26, 27 for 1, 22, 5a, 5b
Since the insertion is performed for positioning, it is not necessary to perform highly accurate alignment at the stage of initially mounting the screen 2 and the substrate 5 in the printing machine, and the number of steps can be reduced. Further, even when the pattern of the screen 2 has a seamless portion, the central portion 2b can be attracted by the electromagnets 24 and 28, so that it is possible to perform printing with the same accuracy as in normal screen printing.

The numbers and positions of the positioning holes and the positioning pins shown in the above embodiment are merely examples, and the present invention is not limited to these. The member to be printed is the substrate 5
Not limited to.

[0018]

As described above, according to the screen printing machine of the present invention, the member to be printed and the screen are positioned at the same time, so that the member to be printed and the screen are first attached to the printer. High-precision alignment is not required at the stage, and the number of steps can be reduced. Even if there is a seamless part in the screen pattern, the screen can be attracted by an electromagnet,
It is possible to perform highly accurate printing that is the same as normal screen printing.

[Brief description of drawings]

FIG. 1 is a front explanatory view showing a configuration of an embodiment of a screen printing machine of the present invention.

FIG. 2 is a plan view showing an example of the screen shown in FIG.

FIG. 3 is a front view showing the shape of a positioning pin shown in FIG.

FIG. 4 is an explanatory diagram showing a printing procedure by the screen printing machine according to the present embodiment.

FIG. 5 is an explanatory front view showing the configuration of an example of a conventional screen printing machine.

FIG. 6 is a plan view showing an example of the screen of FIG.

FIG. 7 is a plan view showing an example of a screen that cannot be conventionally printed.

[Explanation of symbols]

 2 screen 5 substrate (printed member) 7 base 10 paste 26, 27 positioning pin (positioning means) 24, 28 electromagnet (adsorption means)

Claims (2)

[Claims] 1. A screen printing machine for printing a paste on a member to be printed placed on a base through a screen, and positioning for vertically positioning the member to be printed and the screen at the same time on the base. A screen printing machine comprising: a means and a pair of upper and lower suction means which are supported by the base so as to be vertically movable and suction the screen. 2. The screen printing machine according to claim 1, wherein the adsorption means is an electromagnet.