JPH04305454A - Printing apparatus - Google Patents

Abstract

PURPOSE:To perform highly accurate printing by suppressing the deformation and damage of a plate film such as a screen plate, a lithographic plate, a letterpress plate or an intaglio. CONSTITUTION:A press plate 3 is supported so as to be freely revolvable around a shaft 11 and the shaft 11 is positioned so as to become right-angled to the moving direction 7 of a press body 6 at the center of the press plate 3 in the moving direction and extends in parallel to the surface of an object 5 to be printed at height almost equal to that of the surface of the object 5 to be printed. The press plate 3 revolves around the shaft 11 by the movement of the press body 6 but the quantity of revolution thereof is controlled by the elastic pressure body 22 due to a spring 23 and a plate film 1 and an object 5 to be printed are brought to a pressure contact state while the tension of the plate film 1 is held to an appropriate value and the excessive deformation thereof is suppressed. By this constitution printing can be performed with high accuracy using the plate film 1 from end to end.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a high-precision printing device, which stabilizes and improves the dimensional accuracy and quality of lines printed on a workpiece, which is a printing medium, and extends the lifespan of mechanical parts. Regarding extension.

0002

2. Description of the Related Art A screen printing device and a sheet printing device disclosed in Japanese Patent Application No. 3-53466, which was previously proposed by the inventors of the present invention, are known as stencil plates having patterns that form the drawing lines to be printed, as shown in FIG. (screen), a printing plate 3 consisting of a plate film 1 such as lithography, letterpress or intaglio, and a frame 2 to which this plate film 1 is pasted, and a workpiece 5 set on a table 4 are brought close to each other, and a squeegee The plate film 1 is pressed with a pressing body 6 such as 6 to partially contact the surface of the workpiece 5, and then
Printing is performed by moving the pressing body 6 in the direction of the arrow 7 and sequentially moving the contact points 8.

[0003] In addition, in printing devices that use highly adhesive ink or large-sized printing devices, in order to improve plate separation, the printing plate 3 is moved as the pressing body 5 moves, as shown in FIG. In FIG. 5, on the right side, arrow 9 is centered on point P.
I was printing while moving it in the direction of .

0004

[Problem to be solved by the invention] In FIG.
and workpiece 4, there is generally a gap A0 of 0.5 to 3 mm.
The printing plate 1 is pressed against the workpiece 4 by the pressing body 6, and the more the contact point 8 is located at the end of the printing plate 1 in the moving direction of the pressing body 6, the more the printing plate 1 stretches. As the size and tension increase, the pattern formed on the plate film 1 is greatly deformed during printing at the edges, and the dimensional accuracy of the printed image line deteriorates or the image line becomes distorted. is becoming difficult.

[0005] Therefore, when performing printing that requires precision,
It is necessary to limit the pattern installation area only to the range S where the deformation of the plate film 1 is relatively small, making it unsuitable for large-scale printing. Furthermore, a large tension acts on the edges of the printing plate 1, causing permanent deformation and minute breakage of the printing plate 1, resulting in a short service life of the printing plate 1.

Furthermore, as shown in FIG. 5, when moving one end of the printing plate 3, it is necessary to rotate the printing plate 3 around a point P that is distant from the printing plate 3. The gap A1 at the left end is larger than the gap A0 in FIG. 4, and the above-mentioned problem at the end becomes even greater.

An object of the present invention is to reduce the deformation and damage of the printing plate in the above-mentioned printing apparatus, to easily perform high-precision printing, and to enable printing with stable quality.

[0008]

[Means for Solving the Problems] To achieve the above object, the present invention includes a printing plate in which a plate film having a pattern forming the image line to be printed is pasted flat on a frame, and a printing plate on the surface of a printing material. The printing plate placed in close proximity is partially pressed against the surface and is movable from one end of the printing plate to the other end,
A printing device comprising: a pressing body that transfers ink held in the plate film to the surface; a presser body located at the center of the printing plate in the direction of movement of the pressing body, perpendicular to the direction of movement, and approximately equal to the surface; A support that rotatably supports the printing plate around an axis that is located at a height and extends parallel to the surface, and a rotation amount control that controls the amount of rotation of the printing plate in opposition to the pressing force of the pressing body. The rotation amount control means is configured such that the side of the printing plate on which the pressing body is located approaches the surface, and the rotation amount can be changed according to the distance of the pressing body from the axis.

[0009] The rotation amount control means may be a resilient means such as a spring or a fluid pressure device, or a mechanical or electrical interlocking means for rotating the printing plate in accordance with the position of the pressing body. Also,
The printing film may be a screen printing stencil, a sheet printing lithography, a letterpress, or an intaglio.

0010

[Operation] The printing plate rotates around the center of the printing plate as the pressing body moves, and the side on which the pressing body is located, with the center of the printing plate as a boundary, approaches the surface of the printing material. This amount of approach is determined by the rotation amount control means, and does not generate excessive tension on the plate film, but generates appropriate tension. Therefore, highly accurate printing with little deformation is performed over a wide range from one end of the printing plate to the other, and permanent deformation and breakage of the printing plate are suppressed.

[0011]

[Example] The following is an example of the present invention shown in Figs. 1 and 2.
Explain with reference to. Note that the same parts as those shown in FIGS. 4 and 5 are designated by the same reference numerals, and the description thereof will be omitted. Frame 2
In FIG. 1, there is a bracket 10 (see FIG. 2) at the center of the portion extending in the left-right direction (the moving direction of the pressing body 6).
is installed. As shown in Figure 2, bracket 1
A shaft 11 is attached to each of the tables 0 and 4, and each shaft 11 is rotatably attached to mounting bases 13 located on both sides of the table 4 by means of bearings 12.

The center line of the shaft 11, that is, the axis Q, is located at the center of the printing plate 3 in the direction of movement of the pressing member 6 as shown by the arrow 7, and extends at right angles to the direction of movement. Furthermore, the axis Q is located at approximately the same height as the surface of the workpiece 4 and extends parallel to the surface.

As shown in FIG. 1, rotation amount control means 2 for controlling the amount of rotation of the printing plate 3 are provided at the front and rear ends of the table 4.
0 is attached. The rotation amount control means 20 is connected to a guide 21 attached to the table 4, as shown in FIG.
It consists of a resilient body 22 that is engaged to be able to move vertically, and a spring 23 that applies an upward resilient force to the resilient body 22 in FIG. A stopper 24 is provided at the lower end of the pressing body 22, and when the printing plate 3 is in a state parallel to the surface of the workpiece 5 as shown in FIG. The abutting position or a position slightly above the abutting position is set as the upper limit position of the elastic body 22.

Next, the operation of this device will be explained. Application of ink to the printing film 1 is carried out by placing a predetermined amount of ink on the printing film 1 as is well known when the printing film 1 is a stencil for printing, and when the printing film 1 is used for so-called sheet printing. In the case of planographic printing, letterpress printing, or intaglio printing, the printing plate 3 is separated from the workpiece 5 by moving the mount 13, and ink is applied to a pattern provided on the surface of the plate film 1 (lower surface in FIG. 1) using an ink supply device (not shown). Supply and do it. It is preferable that the gap A0 between the surface of the printing plate 1 and the surface of the workpiece 5 is set relatively large, such as about 1 to 6 mm, depending on the length of the printing plate 1, in order to improve mold separation.

As shown in FIG. 1(b), the pressing member 6 is pressed against the right end side in FIG. 1 of the printing film 1 to which the ink has been applied as described above, as indicated by the arrow 25. The pressing force from the pressing body 6 is transmitted to the frame 2 via the printing plate 1, and the frame 2 is moved to the shaft 11.
The pressing body 22 on the right side is pressed down against the spring 23, and the plate film 1 is pressed against the surface of the workpiece 5 by the pressing body 6. At this time, the tension acting on the printing plate 1 is set to an appropriate value depending on the strength of the spring 23, and the frame 2 is rotated to an angle that keeps the printing plate 1 at a relatively small and appropriate amount of elongation.

Next, the pressing body 6 is moved to the left in FIG. 1(b) as shown by the arrow 7, and the ink held in the plate film 1 is transferred to the surface of the workpiece 5 for printing.
As the pressing body 6 moves to the left, the distance from the shaft 11 to the pressing body 6 decreases, so even if the pressing force is constant, the pressing force 22
The pressing force of frame 2 against this decreases. For this reason, the pressing body 2
2 rises as the pressing body 6 moves to the left, reducing the amount of rotation of the frame 2. The amount of rotation of the frame 2 relative to the distance from the shaft 11 of the pressing body 6, that is, the position in the moving direction of the pressing body 6, is determined by the spring 23.
The tension is controlled by appropriately setting the spring constant of , and decreasing the spring force appropriately with respect to the amount of rise of the elastic body 22, whereby the tension of the plate film 1 is also maintained at an appropriate value.

When the pressing body 6 passes through the center of the printing plate 3 in its moving direction, that is, above the shaft 11, the left end of the printing plate 3 descends as shown in FIG. acts similarly to maintain the tension and elongation of the printing plate 1 at appropriate values.

Therefore, according to the present apparatus, as shown in FIG. 1(c), highly accurate printing with little distortion is performed over a wide range S1. Note that the displacement in the left-right direction in FIG. 1 caused by rotation of the printing plate 3 around the shaft 11 can be minimized by setting the axis Q close to the surface of the workpiece 5 or the surface of the plate film 1. It can be held down to Moreover, since this amount of deviation can be calculated in advance, by making corrections when forming the pattern on the printing plate 1, it is possible to print accurate drawing lines that are not affected by this deviation.

Furthermore, since the play in the radial direction of the bearing 12 causes positional deviation, the play can be removed by providing a pro-lead, or by using a combination ball bearing, cross spring bearing,
Furthermore, a special bearing that eliminates play by using a flat bearing and a leaf spring may be used. Furthermore, the elastic body 22 has a spring 2
3, it is preferable to press with a fluid pressure whose pressure can be controlled depending on the position of the pressing body 6.

FIG. 3 shows another embodiment of the present invention.
As the rotation amount control means, a rotation amount control means 30 consisting of a linear actuator 32 equipped with a servo motor 31 that operates in accordance with the position of the pressing body 6 is used. The linear actuator 32 is swingably attached to a member (not shown) that is integral with the mounting base 13 shown in FIG. Possibly connected. According to this device, the amount of rotation of the printing plate 3 can be easily and accurately controlled, and the tension and deformation of the plate film 1 can be adjusted more finely.

In the embodiments described above, a squeegee-like presser for screen printing is shown as the presser 6, but if the printing plate 1 is a planographic, letterpress or intaglio plate, a roller may be used.

[0022]

[Effects of the Invention] As described above, according to the present invention, highly accurate drawing lines can be printed while minimizing deformation of the printing plate, and a wide range from one end of the printing plate to the other can be used. Therefore, it is possible to print a large area with a relatively small printing plate, and as excessive tension does not act on the plate membrane, the life of the plate membrane can be extended, especially for lithography, letterpress, or A great effect can be obtained when applied to sheet printing using an intaglio film.

[Brief explanation of drawings]

FIG. 1 is a schematic longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1(a).

FIG. 3 is a schematic vertical sectional view showing another embodiment of the present invention.

FIG. 4 is a schematic vertical cross-sectional view of a conventional printing device.

FIG. 5 is a schematic vertical cross-sectional view of another conventional printing device.

[Explanation of symbols]

1　Print film 2 Frame 3 Printing plate 4 Table 5　Printed material (work) 6 Pressing body 11 axis 12 Bearing 13 Mounting stand 20, 30 Rotation amount control means 21 Guide 22 Oppression body 23 Spring 31 Servo motor 32 Direct acting actuator

Claims (5)

[Claims] Claim 1: A printing plate in which a printing plate having a pattern forming the image line to be printed is pasted flat on a frame; A printing device comprising: a pressing body that is movable from one end side of the plate film to the other end side while pressing the plate film, and transfers ink held in the plate film to the surface,
Rotating the printing plate about an axis that is located at the center of the printing plate in the moving direction of the pressing body, perpendicular to the moving direction, and located at approximately the same height as the surface and extending parallel to the surface. and a rotation amount control means for controlling the rotation amount of the printing plate in opposition to the pressing force of the pressing body, and the rotation amount control means rotates the printing plate against the pressing body. A printing device characterized in that a side on which is located approaches the surface and is configured to be able to change the amount of rotation depending on the distance from the axis of the pressing body. 2. The printing apparatus according to claim 1, wherein the rotation control means is a pressure means. 3. The printing apparatus according to claim 1, wherein the rotation control means is an interlocking means provided between the two to rotate the printing plate in accordance with the position of the pressing body. Device. 4. The printing apparatus according to claim 1, wherein the printing apparatus is a screen printing apparatus using a stencil as the printing film. 5. The printing apparatus according to claim 1, wherein the plate film is one of a lithographic plate, a letterpress plate, and an intaglio plate.