JP5519482B2 - Screen printing apparatus and screen printing method - Google Patents

Description

  The present invention relates to a screen printing apparatus and a screen printing method for printing paste such as cream solder or conductive paste on a circuit board.

2. Description of the Related Art Conventionally, a squeegee head is provided on a mask plate, and includes a horizontal moving means for moving the squeegee head in a horizontal direction with respect to the mask plate and a lifting means for raising and lowering the squeegee head and a pressing means for pressing the squeegee head against the mask plate A screen printing apparatus and a screen printing method for printing a paste on a substrate through a pattern hole of a mask plate by moving the plate are known (for example, see Patent Document 1).
The screen printing apparatus and the screen printing method described in Patent Document 1 described above can perform stable printing in a sealed squeegee head.

Japanese Patent Laying-Open No. 2006-272584 (FIG. 1, claim 1)

However, in the sealed squeegee head of Patent Document 1, since the paste on the mesh screen is scraped off by the squeegee on the rear side in the printing direction after printing, the paste entering the joint of the mesh screen is exposed to the atmosphere. . As a result, the paste that has entered the joint may dry and become clogged.
Therefore, in the sealed squeegee head disclosed in Patent Document 1, a print defect may occur in the next and subsequent printing.

  SUMMARY An advantage of some aspects of the invention is that it provides a screen printing apparatus and a screen printing method capable of preventing printing defects such as clogging.

  A screen printing apparatus according to the present invention includes a mesh screen disposed substantially parallel to a printing object, and is disposed above the mesh screen, and slides from one end in the surface direction of the mesh screen toward the other end. A sealed head that supplies paste to the printing symmetry through the mesh screen by moving in contact, and is disposed in front of the moving direction of the sealed head above the mesh screen and is synchronized with the sealed head. A paste scraping member that moves, and a paste extending member that is disposed in front of the moving direction of the paste scraping member above the mesh screen and moves synchronously with the sealed head, the sealed head comprising: While moving from the one end side toward the other end side, the paste scraping member is moved to the mesh. The excess paste on the mesh screen is scraped by approaching the lean, the paste extending member is separated from the mesh screen, and the sealed head is moved from the other end side toward the one end side. The paste scraping member is separated from the mesh screen while the paste extending member is close to the mesh screen to extend the excess paste on the mesh screen.

  In the screen printing apparatus according to the present invention, the paste scraping member has a substantially band shape and is close to the surface of the mesh screen substantially perpendicularly.

  In the screen printing method according to the present invention, a mesh screen is arranged substantially in parallel with an object to be printed, and slidably moves from one end side to the other end side in the surface direction of the mesh screen above the mesh screen. Accordingly, a hermetically sealed head for supplying paste to the printing symmetrical object via the mesh screen is disposed, and the paste head that moves synchronously with the hermetic head in the moving direction of the hermetic head above the mesh screen. A paste extending member that moves synchronously with the sealed head in front of the moving direction of the paste scraping member above the mesh screen, and the sealed head is connected to the other from the one end side. While moving toward the end side, the paste scraping member is brought close to the mesh screen. While scraping off excess paste on the mesh screen, the paste extending member is separated from the mesh screen, and while the sealed head is moving from the other end side toward the one end side, The paste scraping member is separated from the mesh screen, and the excess paste on the mesh screen is stretched by bringing the paste stretching member close to the mesh screen.

  According to the screen printing apparatus and the screen printing method of the present invention, it is possible to prevent printing defects such as clogging.

1 is a front view of a screen printing apparatus according to an embodiment of the present invention. 1 is a side view of a screen printing apparatus according to an embodiment of the present invention. The flowchart of the basic operation | movement of the screen printing method of one Embodiment which concerns on this invention. The front view of the 1st step of the screen printing method of one Embodiment concerning this invention The front view of the 2nd step of the screen printing method of one Embodiment concerning this invention The front view of the 3rd step of the screen printing method of one Embodiment concerning this invention The front view of the 4th step of the screen printing method of one Embodiment concerning this invention The principal part front view of the modification of the screen printing apparatus of one Embodiment which concerns on this invention

Hereinafter, a screen printing apparatus and a screen printing method according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2, a screen printing apparatus 10 that executes a screen printing method according to an embodiment of the present invention includes a mesh screen 11, a sealed head 12, and a scraping squeegee that is a paste scraping member. 13 and an ink return 14 which is a paste extending member.

The mesh screen 11 is disposed substantially parallel to the circuit board 15 that is a printing object.
The hermetic head 12 is disposed above the mesh screen 11, and supplies a paste to the circuit board 15 via the mesh screen 11 by slidingly moving from one end side in the surface direction to the other end side of the mesh screen 11. .
The scraping squeegee 13 is disposed in front of the mesh head 11 in the moving direction of the sealed head 12 and moves synchronously with the sealed head 12. The scraping squeegee 13 has a substantially band shape and is close to the surface direction of the mesh screen 11 substantially perpendicularly.
Accordingly, the scraping squeegee 13 is substantially belt-like and close to the mesh screen 11 in a direction substantially perpendicular to the surface direction of the mesh screen 11, thereby preventing printing bleeding without excessively filling the joints of the mesh screen 11 with paste. .
The ink return 14 is disposed in front of the scraping squeegee 13 in the moving direction above the mesh screen 11 and moves in synchronization with the sealed head 12.

  The screen printing apparatus 10 is configured by disposing a screen printing mechanism above the substrate positioning unit 16. The substrate positioning unit 16 includes a Y-axis table 17, an X-axis table 18, and a θ-axis table 19 that are stacked, and a first Z-axis table 20 and a second Z-axis table 21 are combined on these. The circuit board 15 is held by the circuit board receiving part 22 on the second Z-axis table 21.

In the screen printing mechanism, a lead screw 23 is arranged in the Y-axis direction and connected to a prime mover 24, and a nut member 26 included in the head drive mechanism unit 25 is meshed with the lead screw 23. The hermetic head 12 is moved in the vertical direction by the head drive mechanism 25 and is moved in the Y-axis direction via the lead screw 23.
The lead screw 23 has a squeegee drive mechanism 27 for moving the scraping squeegee 13 in the vertical direction and the Y-axis direction with respect to the mesh screen 11 on the side of the head drive mechanism 25, and the ink return 14 on the mesh. An ink return drive mechanism 28 for moving the screen 11 in the vertical direction and the Y-axis direction is engaged. The head drive mechanism 25, the squeegee drive mechanism 27, and the ink return drive mechanism 28 are supported by the base member 29.

  In the screen printing apparatus 10, the scraping squeegee 13 approaches the mesh screen 11 while the sealed head 12 moves from one end side to the other end side of the mesh screen 11 disposed in the screen frame 30. As a result, the excess paste on the mesh screen 11 is scraped off, and the ink return 14 is separated from the mesh screen 11, and the scraping squeegee 13 is moved while the sealed head 12 moves back from the other end side toward the one end side. Is separated from the mesh screen 11 and the ink return 14 comes close to the mesh screen 11 to stretch the excess paste on the mesh screen 11.

Next, the screen printing method will be described.
As shown in FIG. 3, the screen printing method has a basic operation as follows:
Pressurization operation by the sealed head (sealed head) 12 and lowering operation of the scraping squeegee (scraping squeegee) 13 (S101),
Printing operation by paste (S102);
Pressurization stop operation of the sealed head 12, lifting operation of the scraping squeegee 13 and lowering operation of the ink return (ink return) 14 (S103),
It consists of paste coating operation (S104).

Next, the screen printing method will be described in detail.
As shown in FIG. 4, in the first stage, the mesh screen 11 is disposed substantially parallel to the circuit board 15, and the hermetic head 12 is disposed at the position A <b> 1 above the mesh screen 11 to The paste P1 is supplied to the circuit board 15 via the mesh screen 11 by sliding and moving from one end side to the other end side in the surface direction.
At this time, the scraping squeegee 13 moved together with the sealed head 12 is lowered, and the ink return 14 is raised.

  As shown in FIG. 5, in the second stage, the sealed head 12 is moved toward the position A <b> 2, and the scraping squeegee 13 is placed above the mesh screen 11 in the moving direction of the sealed head 12. 12 is moved synchronously. Therefore, the paste P1 on the mesh screen 11 is scraped off by the movement of the scraping squeegee 13 in the Y-axis direction.

As shown in FIG. 6, in the third stage, the ink return 14 is moved synchronously with the sealed head 12 in the moving direction of the scraping squeegee 13 above the mesh screen 11.
At this time, the surplus paste P2 on the mesh screen 11 is scraped off by the scraping squeegee 13 being brought close to the mesh screen 11 while the sealed head 12 is moving from one end side toward the other end side. The scraping squeegee 13 is separated from the mesh screen 11 at the position A <b> 2 of the sealed head 12, and the ink return 14 is brought close to the mesh screen 11.

As shown in FIG. 7, in the fourth stage, the sealed head 12 is moved back from the other end side toward the one end side, and during this time, the excess paste P <b> 2 on the mesh screen 11 is stretched by the ink return 14. At this time, the paste P1 scraped by the scraping squeegee 13 becomes a paste for covering the mesh screen 11. As a result, a paste layer P3 is formed on the mesh screen 11.
Therefore, the scraping squeegee 13 does not fill the paste P1 on the mesh screen 11 in one stroke in which the sealed head 12 moves from one end side to the other end side and then moves back from the other end side to the one end side. Only the scraping operation is performed, and the ink return 14 stretches the excess paste P2 on the mesh screen 11 to form the paste layer P3 on the mesh screen 11, so that the paste surface on the mesh screen 11 is dried. Since the paste P1 in the mesh screen 11 is not dried, the mesh screen 11 can be prevented from being clogged.

As shown in FIG. 8, a modification of the screen printing apparatus 10 according to the embodiment of the present invention includes a pair of scraping squeegees 13 on the mesh screen 11 on both sides of the head drive mechanism 25 on the lead screw 23. A pair of squeegee drive mechanisms 27 for moving in the vertical direction and the Y-axis direction are disposed, and a pair of ink return 14 for moving in the vertical direction and the Y-axis direction with respect to the mesh screen 11 An ink return drive mechanism 28 is disposed.
Therefore, the screen printing apparatus 10 according to the modified example can perform printing both on the forward path from one end side to the other end side of the sealed head 12 and on the return path from the other end side to the one end side of the sealed head 12.

  As described above, according to the screen printing apparatus 10 of the embodiment, after the sealed head 12 is moved from one end side to the other end side, it is scraped in one stroke in which it moves back from the other end side to the one end side. The take-up squeegee 13 performs only a scraping operation without filling the paste P1 on the mesh screen 11, and the ink return 14 extends the excess paste P2 on the mesh screen 11, whereby the paste layer P3 is formed on the mesh screen 11. Since the paste P1 in the mesh screen 11 does not dry even when the paste surface on the mesh screen 11 is dried, printing defects such as clogging of the mesh screen 11 can be prevented.

  In addition, according to the screen printing apparatus 10 of one embodiment, the scraping squeegee 13 is substantially band-shaped and is close to the mesh screen 11 in a direction substantially perpendicular to the surface direction of the mesh screen 11. Printing bleeding can be prevented without excessive filling.

  According to the screen printing method of the embodiment, the scraping squeegee 13 is meshed in one stroke in which the sealed head 12 moves from one end side to the other end side and then moves back from the other end side to the one end side. In order to perform only the scraping operation without filling the paste P1 on the screen 11 and to form the paste layer P3 on the mesh screen 11 by the ink return 14 extending the excess paste P2 on the mesh screen 11, Even if the paste surface on the mesh screen 11 is dried, the paste P1 in the mesh screen 11 is not dried, so that printing defects such as clogging of the mesh screen 11 can be prevented.

  In the screen printing apparatus and the screen printing method of the present invention, the substrate positioning unit, the Y axis table, the X axis table, the θ axis table, the first Z axis table, the second Z axis table, and the like are limited to the above-described embodiment. Appropriate modifications and improvements are possible.

  As described above, according to the screen printing apparatus and the screen printing method of the present invention, the scraping squeegee performs only the scraping operation without filling the paste on the mesh screen. Even if dried, the paste in the mesh screen does not dry, so printing defects such as clogging of the mesh screen can be prevented. As a result, high-quality screen printing can be performed, and the industrial applicability of the present invention can be said to be great.

10 Screen Printer 11 Mesh Screen 12 Sealed Head (Sealed Head)
13 Scraping squeegee (paste scraping member)
14 Ink return (paste stretching member)
15 Circuit board (printed object)

Claims (3)

A mesh screen arranged substantially parallel to the print object;
A sealed head that is disposed above the mesh screen and supplies paste to the printing symmetry through the mesh screen by slidingly moving from one side of the mesh screen toward the other end in the surface direction;
A paste scraping member disposed in front of the moving direction of the sealed head above the mesh screen and moving synchronously with the sealed head;
A paste extending member disposed in front of the moving direction of the paste scraping member above the mesh screen and moving synchronously with the sealed head;
While the sealed head is moving from the one end side toward the other end side, the paste scraping member approaches the mesh screen to scrape excess paste on the mesh screen, and the paste The drawing member is separated from the mesh screen;
While the sealed head is moving from the other end side toward the one end side, the paste scraping member is separated from the mesh screen, and the paste extending member is close to the mesh screen. A screen printing apparatus for stretching the excess paste on the mesh screen. The screen printing apparatus according to claim 1,
A screen printing apparatus in which the paste scraping member is substantially band-shaped and is close to being substantially perpendicular to the surface direction of the mesh screen. The mesh screen is arranged almost parallel to the print object,
Above the mesh screen, arrange a sealed head that supplies paste to the printing symmetry through the mesh screen by slidingly moving from one end side to the other end side in the surface direction of the mesh screen,
A paste scraping member that moves synchronously with the sealed head in front of the moving direction of the sealed head above the mesh screen;
A paste extending member that moves synchronously with the hermetic head in front of the moving direction of the paste scraping member above the mesh screen;
While the sealed head moves from the one end side toward the other end side, the paste scraping member is brought close to the mesh screen to scrape excess paste on the mesh screen, and the paste Separating the stretching member from the mesh screen;
While the sealed head is moving from the other end side toward the one end side, the paste scraping member is separated from the mesh screen, and the paste extending member is brought close to the mesh screen. A screen printing method for stretching the surplus paste on the mesh screen.

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