JPH0438234B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to paper, synthetic resin, ceramic, glass, metal, etc. The present invention relates to a screen printing machine and a printing method thereof that can easily and appropriately print required characters, figures, etc. on the printing surface of various printing materials.

[Conventional technology]

Conventionally, screen printing in this type of screen printing machine has been carried out by a method as schematically shown in FIGS. 6a and 6b. Here, in the figure, numeral 1 is a plate frame, 2 is a screen, 3 is an ink coat sliding plate called a scraper, 4 is its holder, 5 is a printing sliding plate called a squeegee, and 6 is a sliding plate for printing called a squeegee. In the holder, 7 is ink (or paste), 8 is a printing material illustrated as a sheet-like member, and 9
is its mounting table (stage).

In the above-mentioned configuration, first, as a pre-printing step, as shown in FIG. In this state, the scraper 3 and the squeegee 5 are held by the holders 4 and 6 and move to the left, and after coating the screen 2 with ink, stop at the printing start position and move along the imaginary line in the figure. The printing is started as shown in . At this time, the squeegee 5 side is moved to the left while remaining in the raised position.

Next, the scraper 3 is raised on the left side in the figure, as shown in figure b, while the squeegee 5
The squeegee 5 and the scraper 3 in the raised position are lowered together with the holder 6 until it comes into contact with the printing material 8 via the squeegee 2 and the tip of the squeegee 5 is slightly bent.
When the squeegee 5 moves to the right, printing is performed on the printing material 8, and the squeegee 5 stops as shown by the imaginary line in the figure at the printing end, and one printing cycle is completed by moving the squeegee 5 to the right. It is.

[Problem that the invention seeks to solve]

By the way, according to the conventional printing method in which an ink coat is performed before printing as described above, when UV-curable resist ink or the like is used as the ink, the ink may adhere to the printing surface of the printing material 8. , or "print bleeding", which is a problem in ensuring print quality. Due to the nature of the ink, this "printing bleed" is caused by the time elapsed between ink coating and printing, causing a very small amount of ink to wrap around the back side of the screen 2 before printing, or by the ink. This was caused by air bubbles being mixed into the ink during coating. In consideration of such problems, for example, Japanese Patent Application Laid-Open No. 61-280937 discloses a structure in which excess ink is scooped out at the end of printing using a squeegee and a scraper and moved to the start end of printing without contacting the screen. is widely known.

However, with this configuration, it takes a long time to return the ink scooped at the printing start end onto the screen, and it is difficult to completely return the ink on the scraper onto the screen.

Such problems were particularly noticeable when highly viscous ink was used.

[Means for solving problems]

In order to meet such demands, the screen printing machine and the printing method thereof according to the present invention are designed to print from the print start end where ink is placed to the print end end while in contact with the screen placed on the printing substrate. The ink scooping scraper is equipped with a squeegee that moves up to the screen to perform printing, and is moved without contacting the screen when returning, and an ink scooping scraper that moves along with the squeegee on the screen without contacting the screen. has an ink scraping back means, and scoops up ink on the screen by moving up and down at the end of the printing end of the screen, and moves up and down at the printing start end of the screen, and the ink scraping back means scoops up ink on the screen. It is characterized by being configured to scrape back.

[Effect]

According to the present invention, by using an ink scooping scraper, ink is automatically conveyed from a print end position to a print start position without coating the screen with ink at each print cycle, which eliminates the need for conventional printing mechanisms. In addition to being able to perform continuous, appropriate and reliable printing without damage, the ink scraping device attached to this ink scooping scraper allows the ink that has been moved to the printing start end to be quickly and reliably returned to the screen. It is possible.

〔Example〕

Hereinafter, the present invention will be explained in detail using embodiments shown in the drawings.

Figures 1 to 5 show an embodiment of the screen printing machine according to the present invention, and in these figures, parts that are the same as or correspond to those in Figures 6a and b described above are designated by the same numbers. The explanation thereof will be omitted.

First, the general structure of this type of screen printing machine will be briefly explained using FIG. A plate frame receiver 11 is attached to the movable side so as to surround the frame.
On the other hand, on the side of the movable block 12 which is swingably supported with respect to the printing press main body 10 described above, the plate frame 1 is fixed to a holder 13 with a clamp screw 13a, and the holder 13 is It is fastened to the plate frame receiver 11 side with a clamp 13b. In addition, 1 in the figure
Reference numeral 1a denotes a horizontal adjustment bolt that adjusts and supports the plate frame receiver 11, and its function maintains the horizontal state with respect to the stage 9 side. Further, the printing material 8 placed on the stage 9 described above is vacuum-suctioned by a vacuum pump (or blower) 14, and is configured not to be affected by the swinging motion of the movable block 12 described above. Furthermore, numeral 15 in the figure is a fluid pressure cylinder for swinging the above-mentioned movable block 12 around the rotation axis 15a within an angular range in which the printing material 8 can be taken out, and the other configurations are generally as well known. , a detailed explanation thereof will be omitted.

Now, according to the present invention, in the screen printing machine having the above-mentioned configuration, as shown in FIG.
A squeegee 5 moves from a printing start end A, on which ink 7 is placed, to a printing end B to print, and is moved in a non-contact state with the screen 2 when returning, and together with this squeegee 5, the screen An ink scooping scraper 20 that moves on the screen 2 in a non-contact manner is provided with an ink scraping plate 30 as an ink scraping means. By raising and lowering the screen at the end B, the screen 2
The ink 7 on the screen 2 is scooped up and moved up and down at the printing start end A of the screen 2, and the ink 7 is scraped back onto the screen 2 by the ink scraping plate 30.

Here, reference numeral 21 in the figure denotes a tie rod shaft 22 attached to the movable block 12 in order to slide the squeegee 5 and the ink scooping scraper 20 from the printing start end A to the end end B.
is a sliding bearing; 23 is a connecting sliding plate fixed to this; the squeegee 5 and the ink scooping scraper 20 are movable up and down with respect to this sliding plate 23 by lifting cylinders 24 and 25; Supported by hanging. Note that 26 is a forward and reverse rotation motor for reciprocating the squeegee 5 and the ink scooping scraper 20 by driving the connecting sliding plate 23 via a pulley 26a, a belt 27, etc.

The ink scooping scraper 20 has a second ink scooping scraper 20.
As is clear from the figure, it has a substantially L-shape and is fastened to the ink scooping scraper holder 4. Further, the ink scraping back plate 30, which characterizes the present invention, is provided so as to be able to slide on the scooping surface 20a of the scraper 20, and also scrapes the ink 7 onto the screen when the screen 2 moves up and down at the printing start end. A guide shaft 30a and a spring 30 for restoring the guide shaft 30a as means for scraping back onto the
It is connected with b. In addition, in the figure, 31 is a bearing of this scraping plate 30, 32, 33, and 34 are fulcrum bearings that rotate the scraper 20 so that the tip is slightly raised when scooping up the ink 7, and a bolt and an inclination that serve as the fulcrum axis. 3 again with the guide plate for
Reference numeral 5 denotes a receiving plate to which the scraper 20 is attached via bolts 33, and this receiving plate 35 is fixed to a cylinder 36 that is operated when scooping up the ink 7 and a slide guide 37. On the other hand, the cylinder 36 is connected to the lifting cylinder 25 side via a fixing fitting 38, and as a result, the ink scooping scraper 20 portion is suspended and supported by the connecting sliding plate 23. It is said that

Further, the holder 40 on the side of the squeegee 5 includes:
As shown in FIG. 1, etc., a stopper 4 locks the ink scraping back plate 30 to the ink scooping scraper 20 so that it does not operate in conjunction with the ink scooping scraper 20 during scooping.
1, and a stopper 42 that engages with the inclination guide plate 34 to swing the ink scooping scraper 20 during scooping.

According to the screen printing machine configured as described above, at the start of printing shown in FIG.
has been lowered to the screen 2 side, while the ink scooping scraper 20 is in the raised position. In this state, printing is performed by moving these two members to the right in the figure, and the printing is stopped at a print end position B shown by an imaginary line in the figure.

When this printing is completed, the squeegee 5 side rises, the ink scooping scraper 20 side descends to the screen 2 side, and moves forward with the action of the cylinder 36, thereby causing the screen 2 to rise.
The upper ink 7 is scooped up and raised by the cylinder 25 as shown in FIG. At this time, the ink scraping back plate 30 movably disposed on the scraper 20 comes into contact with the stopper 41 on the squeegee 5 side.
On the contrary, it is configured so that it retreats against the biasing force of the spring 30b, and the ink can be easily and appropriately scooped into the scraper 20.

And this ink scooping scraper 20
The ink 7 scooped out at the printing end end B of the screen 2 moves with the squeegee 5 to the printing start end A side without contacting the screen 2, as shown by the imaginary line in the figure, and reaches the required amount. The ink scraping back plate 30, which is biased by the spring 30b, is lowered by the cylinder 25 while stopped at the position and moved backward by the action of the cylinder 36.
is removed from the stopper 41 and moves forward, resulting in the ink 7 being forcibly scraped back onto the screen 2 as shown in FIG.

That is, the present invention focuses on the scraper and squeegee 5 that are moved primarily as a pre-printing step in a conventionally known screen printing machine so that no-coat printing can be performed without any damage to the printing mechanism. As a pre-printing step, the ink 7 scraped up by the squeegee 5 after the previous printing is easily and appropriately scooped out from the top of the screen 2 by using the ink scooping scraper 20 having a special shape. It is inserted between the squeegee 5 and carried to the printing start position without being coated, so that continuous printing can be performed without causing "print smearing" or the like.

Further, according to the present invention, by using the scraping plate 30, even if the ink 7 has a low viscosity, it is easy to completely scoop and transport it and scrape it back from the scraper 20 onto the screen 2. And it can be done reliably.

Therefore, according to the present invention, by using the ink scooping scraper 20, the ink 7 can be automatically moved from the print end position B to the print start position A without coating the screen 2 with ink in each print cycle. It is possible to carry out continuous, appropriate and reliable printing without damaging the conventional printing mechanism. Here, as is well known, in this type of screen printing machine, the movable block 12 is configured to swing to take out the printing material 8 after printing, and in this case, the movable block 12 It will be easily understood that the ink 7 may be conveyed in the inclined state.

Further, according to the screen printing machine according to the present embodiment described above, the ink scooping scraper 20
is configured to be attached and fixed to the holder 32 by a detachable locking means such as a bolt 33, and thereby the ink scooping scraper 2
By attaching a conventionally known scraper 3 for ink coating in place of the screen printing machine 0, the versatility of this type of screen printing machine can be demonstrated.

Note that the present invention is not limited to the structure of the embodiment described above, and the shape, structure, etc. of each part of the screen printing machine are as follows.
It can be modified and changed as necessary,
For example, it will be easily understood that various modifications can be made to the shape and structure of the ink scooping scraper 20, its scraping means, and its operating mechanism.

〔Effect of the invention〕

As explained above, according to the screen printing machine according to the present invention, by using the ink scooping scraper, ink is transferred from the print end position to the print start position without coating the screen with ink in each printing cycle. The ink is automatically transported to the printing start end, allowing for continuous, appropriate and reliable printing without damaging the conventional printing mechanism. There are various excellent effects such as being able to quickly and reliably return images to the screen.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the main parts of an embodiment of a screen printing machine according to the present invention, and FIG. 2 is a schematic perspective view of the ink scooping scraper portion, which is a feature of the screen printing machine.
Fig. 3 is a schematic front view of the entire screen printing machine to which the present invention is applied, Figs. 4 and 5 are explanatory diagrams of the operation of the present invention, and Figs. 6 a and b are diagrams for explaining the conventional screen printing method. It is an explanatory diagram. In the figure, 1...print frame, 2...screen, 4, 6
... Holder, 5 ... Squeegee, 7 ... Ink,
8... Printing material, 9... Stage, 10... Printing machine main body, 12... Movable block, 20... Ink scooping scraper, 24, 25; 36... Cylinder, 30... Ink scraping back plate, A...Printing start edge, B...Printing end edge.

Claims (1)

[Scope of Claims] 1. Printing is performed by moving from the print start end where ink is placed to the print end end while in contact with the screen placed on the printing substrate, and does not contact the screen when returning. a squeegee that is moved in a state of Screen printing characterized in that it is configured to scoop ink on the screen by moving up and down, and to move up and down at the printing start end of the screen so that the ink is scraped back onto the screen by the ink scraping back means. Machine. 2. A screen characterized in that an ink scooping scraper scoops ink at the printing end end of the screen, conveys this ink to the printing start end without contacting the screen, and then scrapes the ink back onto the screen. Printing method.