JPH1052911A - Method and device for printing on material web - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the printing with a stereotype or a printing cylinder, on which no character frame is provided, by a method wherein dots of printing ink are produced on a printing cylinder so as to form a raster image to be printed on a material web out of the dots. SOLUTION: A microcomputer 11 having an image memory arranged on a printing cylinder 1 records the rotary position of the printing cylinder by means of an angular pulse oscillator 12, which co-operates with a machine frame and the signal of which is sent through a line 13 to a microcomputer 11. The microcomputer 11 actuates micro-actuators 7, which are provided on one or a plurality of generating lines passing through a roller gap. At the same time, a shift register 10, which receives the signal read out of the image memory, prints in an instant and actuates the micro-actuators 7 of nozzle opening parts 6 lying on one generating line. Printing ink enters the chamber 8 of the printing cylinder through a rotary transmission lead-through 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for printing a web of material extending between a printing cylinder and a pressure cylinder, and to a printing device for performing this method.

[0002]

2. Description of the Related Art In a conventional printing apparatus, a printing cylinder is provided on a printing cylinder with a printing plate, such as a stencil plate or a frame, which is inked by an inking device or an application roller for transferring a print image. . Printing with print cylinders that support a stele or a frame is relatively expensive because the print cylinders have to be set anew for each new printing sequence.

[0003]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method and a printing apparatus of the above kind which can be printed on a printing cylinder without a printing plate or a frame.

[0004]

According to a first aspect of the present invention,
In a method of printing a web of material passing between a printing cylinder and a pressure cylinder, dots of printing ink are printed along successive generatrix lines according to the raster of the desired print image in the zone of the roller gap formed by the pressure cylinder. A method is provided for printing a material web, wherein said dots are produced in a printing cylinder and draw a raster image to be printed on the material web. The invention relates to a printing zone, i.e. in the zone of the roller gap with the pressure cylinder through which the web of material to be printed runs along the generatrix of the printing cylinder, where the ink dots to be transferred correspond to the raster printed image on the printing cylinder. If provided at a distance from one another, it starts with generating a raster print image from the distribution of raster dots in the raster field of the print image, so that a print image can be generated. Microelectronics provides small elements which, by means of these elements, can provide for each row of dots located on the generatrix a dot of printing ink to be transferred, these dots being the raster printed image to be transferred. Is formed. Based on computer or computer control operations, dots of printing ink can be formed one after the other on the generatrix to produce the desired raster print image on the material web as these dots pass through the roller gap.

According to a second aspect of the present invention, in a printing apparatus having a printing cylinder and a pressure cylinder, the printing cylinder is provided with holes along its generatrix, and the hole of each generatrix is used to print a printed image. Having a mutual spacing corresponding to the raster, the holes communicating with one or more supply lines for printing ink, or a chamber containing printing ink,
A microactuator consisting of a micropump or microvalve is arranged in or on the hole, and a control unit for the microactuator is provided, which controls the angular position of the bus bar during rotation of the printing cylinder. To actuate and open the holes in each case in the zone of the roller gap formed by the pressure cylinder,
Alternatively, a printing device is provided, which is effective for supplying printing ink to the opening of the hole with the desired image to be printed.

When the microactuator comprises a pump, each of these pumps, when activated, delivers a drop of printing ink which is effective at the opening of the corresponding hole and prints when passing through the roller gap. The material web to be sucked up. If the microactuator comprises microvalves, opening each microvalve causes a drop of pressurized printing ink to be pumped from the reservoir to the opening of the aperture, which is sucked up by the web of material.
Since the microactuator can be actuated linearly, for example by means of a shift register, it is possible to produce a printed image by means of a control operation without using a plate or a master such as a stero plate. It is not necessary to arrange the individual holes for setting the raster image of the printed image on a common generating line.
These holes can also be arranged in each case offset from the generatrix. The only prerequisite is that the opening of the hole in the outer cylinder of the printing cylinder has essentially the same raster as the raster print image to be printed.

These holes preferably lead to small cups formed in the outer cylinder of the printing cylinder. Advantageously, these small cups are already covered by the passing material web in the zone of the roller gap,
Only the printing ink is filled by the microactuator. The micropump or microvalve preferably consists of a microactuator manufactured by chip technology (planarization technology). These microactuators may be integrated into the chip layer or aligned with the holes. The chip layer may form the printing cylinder outer cylinder itself or an intermediate layer. A microactuator composed of a micropump and a microvalve is, for example, 19
"Physik in unserer Zelt" in 1993 [Physics in our T
ime]. Zengere and A. Published by Riccia, Franhofagel Shaft 111-92 "Electrostatically actuated micro-membrane pump""Elektrostatisch betriebene mi
kro-Membranpumpen "[Electrostatically operated mic
romembrane pumps], pages 86-90 of the in-house gazette, and in the publication of the Association of Solid State Technology Franchoffers, a contribution to Actuator '94, "Microdiaphragm Pumps in Microfluidic Systems".
In these publications, the microactuators described clearly have dimensions that do not correspond to the raster of the printed image, but the microelectronics or chip technology has to employ small microactuators that will fit the printed image raster in the foreseeable future. It is expected to provide.

Advantageously, the microprocessor is arranged on the printing cylinder and, during rotation of the cylinder, activates a microactuator constituted by a micropump or microvalve of each line depending on the angular position of each line, and thus the image memory. Control the microactuator according to the data read from the. Also, another computer may be provided for communicating with the microprocessor of the printing cylinder by means of the contact created by the at least one slip ring and for supplying the image to be printed to the microprocessor of the printing cylinder. The printing cylinder may be configured as a hollow cylinder and may contain an inking chamber communicating with the holes, and the printing ink is sent to said chamber via a rotary transfer lead-through.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A printing cylinder 1 and a pressure cylinder 2 are mounted in a conventional manner on a machine frame (not shown). Intermeshing gears 3, 4 are keyed to the shafts of the printing cylinder 1 and the pressure cylinder 2, one of these gears meshing with a drive gear so that both cylinders are driven at the same peripheral speed. The printing cylinder 1 is designed as a hollow cylinder,
An array of radial holes 5 with openings 6 in the cylindrical surface of the printing cylinder 1 is provided along the generatrix. In each row, the holes 5 or their openings 6 have a mutual spacing corresponding to the raster of the print image. Moreover, in the circumferential direction, the rows of holes or openings also have a mutual spacing corresponding to the raster of the print image.

In the hole 5, there is arranged a microactuator 7, which may consist of a micropump or microvalve. The radial bore 5 starts from a central cylindrical chamber 8, which is filled with printing ink which is subjected to an excessive pressure (relative to atmospheric pressure).
As shown in FIG. 1, the microactuator 7 is provided with actuating devices 9, which are controlled by an electronic control unit for actuating the microactuator 7, preferably a microprocessor of a microcomputer. You. In the example of the embodiment shown in FIG. 2, the microcomputer having the image memory is the printing cylinder 1.
The computer records the rotational position of the printing cylinder 1 by means of an angular pulse oscillator 12 cooperating with the machine frame. The signal of the angular pulse oscillator 12 is sent to the microcomputer 11 via the line 13. The microcomputer 11 operates a microactuator arranged on one or more buses passing through the roller gap. At the same time, the signal read from the image memory is conveniently sent to a shift register 10 which prints instantaneously and activates the microactuator 7 of the nozzle opening 6 on one bus line. .

The printed image is processed by a microcomputer 16 connected to the microcomputer 11 by lines 17 and 18 and a slip ring 19.
Sent to The printing ink is sent to the chamber 8 of the printing cylinder 1 via the rotation transmission lead-through 20. In the drawing, only one printing unit is shown schematically. If multi-color printing has to be carried out, it is possible to arrange some of the printing units according to the invention, which print with different printing ink colors, in an alternative manner in the usual way. The printing cylinder preferably has a circumference smaller than the length of the image to be printed. In such a printing apparatus, just before passing through the roller gap in accordance with the raster dots to be printed instantaneously, the nozzle opening 6 on the bus line of the printing cylinder is not used.
Can be operated by a microcomputer, so that the printing cylinder can be designed to have a small diameter as desired. This is advantageous only from the manufacturing cost.

If the printing ink is provided by the microactuator in small cups on the cylindrical surface of the printing cylinder through which the microholes pass, the printing ink is sucked out of these small cups by the web passing through the printing gap due to the adhesion. .

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a printing cylinder and a pressure cylinder through which a material web to be printed passes.

FIG. 2 is a schematic front view of a printing cylinder and a pressure cylinder showing the printing cylinder in a schematic sectional view.

FIG. 3 is a sectional view of the printing cylinder along the line III-III in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing cylinder 2 Pressure cylinder 5 Hole 6 Opening 7 Microactuator 8 Cylindrical chamber 9 Actuator 11 Microcomputer 12 Oscillator

Claims (9)

[Claims] 1. A method for printing a web of material passing between a printing cylinder and a pressure cylinder, comprising the steps of:
In the zone of the roller gap formed by the printing cylinder (1) along the successive generating lines according to the raster of the desired print image, said dots being the raster to be printed on the material web. A method for printing a material web, characterized by drawing an image. 2. The method according to claim 1, wherein the peripheral speed of the printing cylinder is shorter than the length of the image to be printed. 3. A printing apparatus having a printing cylinder (1) and a pressure cylinder (2), comprising: a printing cylinder (1);
Are provided with holes (5) along their generatrix, the holes (5) of each generatrix having a mutual spacing corresponding to the raster of the print image, and the holes (5) for the printing ink. A microactuator (7) comprising a micropump or microvalve is in communication with one or more supply lines or chambers (8) containing printing ink and in or on the holes (5). ) Are provided, and a control unit (11) for the microactuator is provided, which controls the pressure cylinder (2) according to the angular position of the bus bar during rotation of the printing cylinder. In the zone of the roller gap formed by (1) and (2), the printing ink is supplied to the opening (6) of the hole for actuating and opening the holes (5, 6) in each case or with the desired image to be printed. That is effective for Printing apparatus according to claim. 4. The printing device according to claim 3, wherein the holes (5) lead to small cups formed in the cylindrical surface of the printing cylinder (1). 5. The printing apparatus according to claim 3, wherein the micropump or the microvalve comprises a microactuator manufactured by chip technology. 6. The printing device according to claim 3, wherein the micropump or the microvalve is integrated in a chip layer in which the microactuator is aligned with the hole. . 7. A microprocessor (11) is arranged in the printing cylinder (1), said microprocessor (11) actuating a micro-actuator formed by a micro-pump or micro-valve in each line depending on the angle. 7. The printing apparatus according to claim 3, wherein the micro actuator is controlled by data read from the image memory. 8. The microcomputer (1) of the printing cylinder (1) by means of a contact produced by a slip ring.
8. A printing device according to claim 3, further comprising a computer in communication with 1) and for sending an image to be printed to a microcomputer. 9. The printing cylinder (1) is designed as a hollow cylinder, has an inking chamber (8) communicating with the hole (5) and has a lead-through (20) for rotary transfer of printing ink. The printing device according to any one of claims 3 to 7, wherein the printing device is sent to the room (8) via a second device.