Shaftless color register system of intaglio printing press

Abstract

The invention discloses a shaftless color register system of a gravure press. The shaftless color register system comprises an industrial personal computer, a transmission mechanism and a plurality of printing assemblies. Each printing assembly is used for printing one color, and the multiple printing assemblies form a complete pattern after printing of patterns of multiple colors is completed; each printing assembly comprises a printing mechanism and an ink feeding mechanism, the printing mechanism comprises a printing roller and an impressing roller, and ink of the printing roller is transferred to a printing material through opposite rolling of the impressing roller and the printing roller; the ink feeding mechanism comprises an ink fountain and a doctor blade, the printing roller is partially immersed into the ink fountain filled with printing ink, the printing ink enters a groove of the printing roller, and the doctor blade is used for scraping redundant printing ink on the printing roller; the transmission mechanism comprises a plurality of conveying rollers and is used for driving a printing material to move; tension sensors are arranged on the conveying rollers at the front end and the rear end of each printing assembly; the industrial personal computer can compare a tension value measured by the tension sensor with a preset value and finely adjust the rotating speed of the corresponding conveying roller according to a comparison result.

Description

Technical Field

[0001] The present invention relates to the technical field of intaglio printing machines, and in particular to a shaftless color registration system for an intaglio printing machine. Background Art

[0002] The initial intaglio printing machine adopted a mechanical shaft drive method, where a single motor drove the mechanical main shaft, and each rotating shaft in the printing unit was connected to the main shaft through a worm and worm gear mechanism and a gearbox, and rotated synchronously under the drive of the main shaft. Under such a drive method, the synchronization performance of the unit was good, and the noise of mechanical operation was small. However, manual adjustment was required at the start of printing, and the degree of automation was low. With the rapid development of technologies such as computer technology, network communication technology, motor control, and information automation, shaftless drive technology was introduced into the intaglio printing industry and quickly became the mainstream drive method for modern printing machines.

[0003] In an intaglio printing machine adopting shaftless drive technology, the mechanical main shaft was omitted, and each unit adopted an independent servo system. The servo motors exchanged data with each other through a fieldbus or directly with the controller, and a virtual electronic shaft was formed by the network and program software. The servo drivers of each unit drove the motors to rotate along with the virtual electronic shaft, realizing the synchronous control of the units and meeting the requirements of specific operating speeds, operating accuracies, and printing processes.

[0004] During the transmission of the printing material, its tension is related to the transmission speed, size, moisture content, etc. of the printing material; the tension change and tension transmission during the transmission process are likely to cause color registration errors. In order to reduce color registration errors, the current solution is usually to design a more precise control algorithm to achieve more precise synchronous control of the units. However, such a method cannot fundamentally solve the problem. Summary of the Invention

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A shaftless color registration system for an intaglio printing machine includes an industrial control computer, a transmission mechanism, and a plurality of printing components;

[0007] The industrial control computer is used to realize the comprehensive control of the shaftless color registration system of the intaglio printing machine;

[0008] Each printing component is used to print one color. After a plurality of printing components complete printing patterns of a plurality of colors, a complete pattern is formed;

[0009] Each printing component includes a printing mechanism and an inking mechanism. For any one printing component:

[0010] The printing mechanism includes a printing roller and an impression roller, and the ink on the printing roller is transferred to the printing material through the rolling of the impression roller and the printing roller;

[0011] The ink supply mechanism includes an ink tank and a doctor blade. The printing roller is partially immersed in the ink tank filled with ink, so that the ink enters the grooves of the printing roller. The doctor blade is used to scrape off the excess ink on the printing roller;

[0012] The transmission mechanism includes a plurality of conveyor rollers for driving the printing material to move;

[0013] Moreover, tension sensors are arranged on the conveyor rollers at the front end and the rear end of each printing assembly for detecting the tension of the printing material;

[0014] The industrial control computer can compare the tension value measured by the tension sensor with a preset value and fine-tune the rotation speed of the corresponding conveyor roller according to the comparison result.

[0015] In some embodiments, for each conveyor roller equipped with a tension sensor, its outer surface is provided with an uneven coating layer for increasing the friction between the printing material and the conveyor roller.

[0016] In some embodiments, a color difference detection mechanism is arranged at the rear end of each printing assembly. The color difference detection mechanism is used for detecting the overprint color difference.

[0017] In some embodiments, a drying mechanism is arranged at the rear end of each printing assembly. The drying mechanism is used for drying the ink on the printing material.

[0018] In some embodiments, the color difference detection mechanism adopts a photoelectric sensor, and the drying mechanism adopts a drying oven.

[0019] In some embodiments, a unwind mechanism and a rewind mechanism are further included;

[0020] The unwind mechanism is used for unwinding the coil material of the printing material and stably and continuously conveying the printing material to the first conveyor roller of the transmission mechanism;

[0021] The rewind mechanism is used for rewinding and recycling the printing material after printing.

[0022] In some embodiments, each printing assembly is further equipped with a color registration control box as the slave computer of the industrial control computer, and the industrial control computer centrally controls all color registration control boxes.

[0023] In some embodiments, a communication gateway is further included. The communication gateway realizes master-slave communication with each color registration control box through a CAN bus, and the communication gateway is wirelessly connected to the industrial control computer through an Ethernet.

[0024] Compared with the prior art, the beneficial effects of the shaftless color registration system of the gravure printing machine provided by the present invention are as follows: Each printing unit is driven by a servo motor, and the position information is fed back by an optoelectronic encoder, with high positioning accuracy, thus improving the registration accuracy. In addition, each printing unit can be controlled independently, and the instructions of the host computer act directly on the servo motor through a high-speed fieldbus, making the system respond faster, thus improving the printing speed; moreover, tension sensors are arranged on the conveying rollers at the front end and the rear end of each printing component, so as to be able to finely adjust the rotation speed of the corresponding conveying roller in real time to adjust the tension of the printing material during the transmission process and reduce the color registration error. Brief Description of the Drawings

[0025] Figure 1 It is a partial structural schematic diagram of the shaftless color registration system of the gravure printing machine provided by the present invention;

[0026] Figure 2 It is a connection schematic diagram among the color registration control box, the communication gateway and the industrial control computer.

[0027] Explanation of the Reference Numerals in the Drawings:

[0028] 1. Printing roller; 2. Impression roller; 3. Ink tank; 4. Doctor blade; 5. Conveying roller; 6. Color difference detection mechanism; 7. Drying mechanism; 8. Color registration control box; 9. Communication gateway; 10. Industrial control computer. Detailed Embodiments

[0029] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments on how it is implemented.

[0030] Referring to Figure 1 As shown, in a specific embodiment, the present invention provides a shaftless color registration system for a gravure printing machine, including an industrial control computer 10, a transmission mechanism and a plurality of printing components; the industrial control computer 10 is used to realize the comprehensive control of the shaftless color registration system of the gravure printing machine; each printing component is used to print one color, and after a plurality of printing components print the patterns of a plurality of colors, a complete pattern is formed; each printing component includes a printing mechanism and an ink supply mechanism. For any one printing component: the printing mechanism includes a printing roller 1 and an impression roller 2, and the ink on the printing roller 1 is transferred to the printing material by the impression roller 2 rolling against the printing roller 1; the ink supply mechanism includes an ink tank 3 and a doctor blade 4, and a part of the printing roller 1 is immersed in the ink tank 3 filled with ink, so that the ink enters the groove of the printing roller 1, and the doctor blade 4 is used to scrape off the excess ink on the printing roller 1; the transmission mechanism includes a plurality of conveying rollers 5, which are used to drive the printing material to move; moreover, tension sensors are arranged on the conveying rollers 5 at the front end and the rear end of each printing component, which are used to detect the tension of the printing material; the industrial control computer 10 can compare the tension value measured by the tension sensor with a preset value, and finely adjust the rotation speed of the corresponding conveying roller 5 according to the comparison result.

[0031] Preferably, for each transfer roller 5 equipped with a tension sensor, its outer surface is provided with an uneven coating layer for increasing the friction between the printing material and the transfer roller 5.

[0032] Preferably, a color difference detection mechanism 6 is provided at the rear end of each printing assembly. The color difference detection mechanism 6 is used to detect the overprint color difference.

[0033] Preferably, a drying mechanism 7 is provided at the rear end of each printing assembly. The drying mechanism 7 is used to dry the ink on the printing material.

[0034] The color difference detection mechanism 6 can adopt a photoelectric sensor, and the drying mechanism 7 can adopt a drying oven.

[0035] Preferably, the shaftless color register system of the gravure press further includes an unwinding mechanism and a winding mechanism (not shown in the figure); the unwinding mechanism is used to unwind the coil of the printing material and stably and continuously convey the printing material to the first transfer roller 5 of the transmission mechanism; the winding mechanism is used to rewind and recover the printing material after printing.

[0036] Referring to Figure 2 As shown, preferably, each printing assembly is further equipped with a color register control box 8, which serves as a slave computer of the industrial control computer 10, and the industrial control computer 10 centrally controls all color register control boxes 8.

[0037] Preferably, it further includes a communication gateway 9. The communication gateway and each color register control box 8 perform master-slave communication through the CAN bus, and the communication gateway 9 is wirelessly connected to the industrial control computer 10 through the Ethernet.

[0038] In summary, for the shaftless color register system of the gravure press provided by the present invention, each printing unit is driven by a servo motor and uses an optical encoder to feedback position information, with high positioning accuracy, thus improving the register accuracy. In addition, each printing unit can be controlled independently, and the instructions of the upper computer directly act on the servo motor through the high-speed field bus, making the system respond faster, thus improving the printing speed; and, tension sensors are configured on the transfer rollers at the front end and the rear end of each printing assembly, so as to be able to finely adjust the rotation speed of the corresponding transfer roller in real time to adjust the tension of the printing material during transmission and reduce the color register error.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A shaftless color registration system for a gravure printing machine, characterized in that: It comprises an industrial computer (10), a transmission mechanism and a plurality of printing components; The industrial computer (10) is used to realize the comprehensive control of the shaftless color registration system of the gravure printing machine; Each printing component is used to print one color, and after multiple printing components print patterns of multiple colors, a complete pattern is formed; Each printing component includes a printing mechanism and an ink supply mechanism. For any printing component: The printing mechanism comprises a printing roller (1) and an embossing roller (2), and the ink on the printing roller (1) is transferred to the printing material by the embossing roller (2) and the printing roller (1) rolling against each other; The ink supply mechanism comprises an ink tank (3) and an ink scraper (4); the printing roller (1) is partially immersed in the ink tank (3) filled with ink so that the ink enters the groove of the printing roller (1); and the ink scraper (4) is used to scrape off excess ink on the printing roller (1); The transmission mechanism comprises a plurality of conveying rollers (5) for driving the printing material to move; Furthermore, the conveying rollers (5) at the front and rear ends of each printing assembly are provided with tension sensors for detecting the tension of the printing material; The industrial computer (10) is capable of comparing the tension value measured by the tension sensor with a preset value, and fine-tuning the rotation speed of the corresponding conveying roller (5) according to the comparison result.

2. The shaftless color registration system of the gravure printing machine according to claim 1, characterized in that: For each conveying roller (5) equipped with a tension sensor, an uneven coating layer is provided on its outer surface to increase the friction between the printing material and the conveying roller (5).

3. The shaftless color registration system of the gravure printing machine according to claim 1, characterized in that: A color difference detection mechanism (6) is provided at the rear end of each printing component, and the color difference detection mechanism (6) is used to detect overprint color difference.

4. The shaftless color registration system of the gravure printing machine according to claim 3, characterized in that: A drying mechanism (7) is provided at the rear end of each printing component, and the drying mechanism (7) is used to dry the ink on the printing material.

5. The shaftless color registration system of the gravure printing machine according to claim 4, characterized in that: The color difference detection mechanism (6) adopts a photoelectric sensor, and the drying mechanism (7) adopts a drying box.

6. The shaftless color registration system of the gravure printing machine according to claim 1, characterized in that: It also includes an unwinding mechanism and a rewinding mechanism; The unwinding mechanism is used to unwind the coil of the printing material and stably and continuously transport the printing material to the first conveying roller (5) of the transmission mechanism; The rewinding mechanism is used to rewind and recycle the printing material after printing is completed.

7. The shaftless color registration system of the gravure printing machine according to claim 1, characterized in that: Each printing component is also equipped with a color register control box (8) which serves as a lower computer of the industrial control computer (10). The industrial control computer (10) performs centralized control over all the color register control boxes (8).

8. The shaftless color registration system of the gravure printing machine according to claim 7, characterized in that: It also includes a communication gateway (9), wherein the communication gateway and each color matching control box (8) realize master-slave communication via a CAN bus, and the communication gateway (9) is wirelessly connected to an industrial computer (10) via Ethernet.

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