Printing machine with hybrid printing technology

11951733 ยท 2024-04-09

Assignee

Inventors

Cpc classification

International classification

Abstract

The invention relates to a printing machine with hybrid printing technology for printing on a continuous material web. In order to create a printing machine with hybrid printing technology which is adaptable and flexible in use in the course of the current trend for digitization, the printing machine with according to the invention, hybrid printing technology for printing a continuous material web, is a printing machine with a rotating central cylinder, on the surface of which the material web is guided from a placement point to a separation point for printing; a plurality of inking units for digital printing of the material web are arranged in the region of an upper half of the central cylinder, and a plurality of inking units for flexographic printing of the material web are arranged in the region of a lower half of the central cylinder; an unwinding station is provided for unwinding the material web to be printed from a roll and a winding station is provided for winding the printed material web onto a roll, the unwinding station and the winding station being arranged on a first side of the central cylinder, with supply guide rollers for feeding the material web unwound from the unwinding station to the central cylinder and with discharge guide rollers for discharging the printed material web from the central cylinder to the winding station; the feed guide rollers and the discharge guide rollers being arranged on a second side of the central cylinder, with a feed guide roller for placing the material web onto the central cylinder at the placement point and a strip guide roller for detaching the material web from the central cylinder, the feed guide roller and the strip guide roller being designed in such a way that the placement point and the separation point are arranged on the lower quadrant of the central cylinder.

Claims

1. Printing machine with hybrid printing technology for printing a continuous material web, comprising: a rotating central cylinder, on the surface of which the material web is guided from a placement point to a separation point for printing, wherein a plurality of inking units for digital printing of the material web are arranged in the region of an upper half of the central cylinder and a plurality of inking units for flexographic printing of the material web are arranged in the region of a lower half of the central cylinder; an unwinding station for unwinding the material web to be printed from a roll and a winding station for winding the printed material web onto a roll, wherein the unwinding station and the winding station are arranged on a first side of the central cylinder; supply guide rollers for feeding the material web unwound from the unwinding station to the central cylinder and discharge guide rollers for discharging the printed material web from the central cylinder to the winding station, wherein the supply guide rollers and the discharge guide rollers are arranged on a second side of the central cylinder, feed guide roller for placing the material web onto the central cylinder at the placement point and a strip guide roller for detaching the material web from the central cylinder, wherein the feed guide roller and the strip guide roller are designed in such a way that the placement point and the separation point are arranged on the lower quadrant of the guide cylinder.

2. Printing machine according to claim 1, wherein the material web is selected from the group consisting of a plastic film, a plastic film substitute, an aluminum web, a paper web, and combinations thereof.

3. Printing machine according to claim 1, wherein four inking units for flexographic printing are arranged in the region of the lower half of the central cylinder and eight inking units for digital printing are arranged in the region of the upper half of the central cylinder.

4. Printing machine according to claim 1, wherein two inking units for flexographic printing are arranged after the placement point and two inking units for flexographic printing are arranged before the separation point.

5. Printing machine according to claim 4, wherein the two inking units for flexographic printing are furnished after the placement point, for applying at least one of a primer, a partial primer, and a full-surface colored primer.

6. Printing machine according to claim 4, wherein the two inking units for flexographic printing are furnished before the separation point, for finishing the printed material web.

7. Printing machine according to claim 1, wherein a drying station for drying the printed material web is arranged on said first side of the central cylinder before the winding station.

8. Printing machine according to claim 1, further comprising a digital printing shutoff device, so that the printing machine may be operated purely as a flexographic printing machine.

9. Printing machine according to claim 1, further comprising a flexographic printing shutoff device, so that the printing machine may be operated purely as a digital printing machine.

10. Printing machine according to claim 1, wherein the inking units for digital printing consist of inking units for inkjet printing.

11. Printing machine according to claim 10, wherein inserts are furnished for the inkjet inking units in such a way that the inking units for inkjet printing are interchangeable in their positions.

12. Printing machine according to claim 11, further comprising a star-shaped ink supply of such a kind that the insert is automatically supplied with the printing ink corresponding to the inking unit for inkjet printing located in the insert.

Description

(1) Additional details and advantages of the invention will be described with reference to the attached drawings.

(2) FIG. 1 shows a schematic representation of the spatial relationships on the central cylinder of the printing machine according to the invention,

(3) FIG. 2 shows a perspective view of the printing machine according to the invention, and

(4) FIG. 3 shows a side view of the printing machine according to the invention.

(5) FIG. 1 shows a schematic diagram of the spatial relationships on the central cylinder of the printing press according to the invention. By way of a description of the spatial relationships, it is assumed without loss of generality that the central cylinder 101 rotates clockwise 102 within the stationary coordinate system with a horizontal x-axis and a vertical y-axis, and the origin of the coordinate system is located at the center of rotation of the central cylinder 101. Moreover, the gravity vector 103 is oriented parallel to the y-axis in the negative y-direction.

(6) In this constellation, the upper half 104 of the central cylinder 101 refers to the space above the x-axis, while the lower half 105 of the central cylinder 101 defines the space below the x-axis.

(7) Correspondingly, the left side 106 of the central cylinder 101 refers to the space to the left of the y-axis, while the right side 107 of the central cylinder 101 defines the space to the right of the y-axis.

(8) Finally, the central cylinder 101 is divided into 4 quadrants Q1, Q2, Q3 and Q4, where quadrant Q1 is in the range 45? to 135?, quadrant Q2 is in the range 135? to 225?, quadrant Q3 is in the range 225? to 315? and quadrant Q4 is in the range 315? to 45?. From the preceding definitions, it also follows that quadrant Q1 is the upper quadrant, quadrant Q3 is the lower quadrant, quadrant Q2 is the left quadrant, and quadrant Q4 is the right quadrant.

(9) FIG. 2 shows a perspective view of the printing machine according to the invention. In principle, the printing machine according to the invention consists of a central cylinder 201, in which eight inking units for inkjet printing 202 (which are collectively labeled with one reference number for the sake of simplicity) are arranged in the region of the upper half of the central cylinder and four inking units for flexographic printing 203 (which are collectively labeled with one reference number for the sake of simplicity) are arranged in the region of the lower half of the central cylinder. Arranging the inkjet inking units 202 in the region of the upper half of the central cylinder 201 enables error-free operation of the inking units for inkjet printing without the influence of the gravity vector negatively becoming noticeable in the print image. In contrast, it was found that the quality of the inkjet print deteriorates if the inking units for inkjet printing have to be operated in the region of the lower half of the central cylinder 201. Thus, it is particularly advantageous for the inking units for inkjet printing to be arranged in the region of the upper half of the central cylinder 201.

(10) For printing, the material web 204 is guided from the unwinding station 205 to the central cylinder 201. The finished printed material web is rewound at the winding station 206.

(11) A housing 207 is located on the left side of the central cylinder 201. In the housing 207, there are arranged supply guide rollers for supplying the material web 204 that has been unwound by the unwinding station 205 to the central cylinder 201, and discharge guide rollers for discharging the printed material web from the central cylinder 201 to the winding station 206.

(12) A drying station 208 is located on the right side of the central cylinder 201; the drying station for drying the printed material web is arranged before the winding station 206. FIG. 3 shows a side view of the printing machine according to the invention. The components already described as shown in FIG. 2 are marked with the same reference numbers, so that in that regard reference is made to the description according to FIG. 2. In addition, the web guide of the material web 204 is described in detail below:

(13) From the unwinding station 205, the material web 204 passes to the feed guide rollers 301 (which are labeled jointly with a single reference number for the sake of simplicity) located on the left side of the central cylinder in the housing 207. The supply guide rollers 301 guide the material web further to the feed guide roller 302, and from there the material web reaches the placement point 303 on the surface of the central cylinder 201.

(14) On the surface of the central cylinder 201, the material web is guided with precision past the individual inking units 202 and 203. At the separation point 304, the material web is then detached by the strip guide roller 305 in a defined manner from the surface of the central cylinder 201. The placement point 303 as well as the separation point 304 are located in the region of the lower quadrant Q3 of the central cylinder 201. In this way, the material web can be discharged to the drying station 208 after flexographic printing, without the printed side of the material web coming into any further contact with a guide roller until it reaches a drying station.

(15) From the separation point 304, the material web passes to the discharge guide rollers 306 (which are labeled jointly with a single reference number for the sake of simplicity), which are likewise located on the left side of the central cylinder in the housing 207. The discharge guide rollers 306 guide the material web further to the drying station 208, where the printed side of the material web is dried prior to being wound at the winding station 206.