Working principle of printing proofing machine

(A) the working principle of the proofing machine

At present, most box-type proofing machines at least include the following components: machine table (including workbench); Electrical control and driving part; Vacuum adsorption system; Combined tool head (cutting/wire pressing/wire drawing); Graphic transmission and operating system, etc. Some prototypes must also have compressed air systems.

The file graphics processed by professional software include the indentation line type and cutting line type (corrugated paper/paperboard/film paper) required by the actual box sample, and may also include dimension marking and file marking. (cardboard/film paper, etc. ). Install different tools/rollers/drawing tools according to actual needs, and transmit them to the machine in a certain format through the network or data cable. The machine will automatically recognize various line shapes in the drawing and select the corresponding tool (knife/roller/pen). At the same time, it will work according to the corresponding parameter settings, such as working speed, tool type, cutting depth of blade, indentation depth and so on. , and complete the box sample or drawing. In the past, grotesque cartoons and puzzles could only be made with die-cutting boards, but some three-dimensional boxes and articles could not be designed at once, and they had to be revised and assembled repeatedly to achieve real results. The competition in the consumer market is becoming increasingly fierce, and rapidly changing consumer goods are constantly vying for their own development space. Therefore, it is normal for manufacturers to change the packaging design more frequently in order to grasp the market initiative. The design cycle has been shortened from the previous weeks to a few days, and the production cycle of packaged products has become shorter and shorter. Everyone is striving for more orders than product quality and delivery speed, striving to stabilize the old customer base, and at the same time developing and expanding new customers as much as possible, so that the operation of the whole factory and company is in a benign state.

The prototypes produced by different manufacturers have their own characteristics, and they have their own advantages in shape design, machine structure and control.

It adopts advanced CNC controller and the latest control technology, selects high-quality drive system and Chinese color touch screen, and has the functions of manual, automatic, material and diagnosis. The working file can be called quickly through local area network connection, and the cutting consistency can be ensured through the function of high automatic compensation. Z-axis motor controls the depth of cutting/indentation, and the adjustment is simple and flexible. Customers no longer need to configure compressors, and all tools are very convenient to install and replace. The combination of tools is flexible and diverse. General standard configuration includes cardboard cutting/line pressing tool, corrugated paper cutting/line pressing tool, drawing tool and blades and rollers with different specifications (0.7 1mm, 1.05mm, etc. ) to suit different materials.

Powerful software compatibility function, you can get the designed samples directly, and then produce them after proofreading, which reduces the loss and saves the printing and die-cutting time on the computer, thus reducing the production cost and improving the competitiveness of enterprises. On the other hand, many orders now require fast delivery, and traditional manual methods cannot guarantee the output and quality of samples in a short time. The high speed and precision of the prototype can ensure that the sample can be designed in the shortest time, and the production can be arranged after the customer confirms it, which is of great help to developing new customers. R&d of factory or company; In Part D, the prototype can be seen as soon as it is typed, that is, it can be changed as soon as it is seen, which can let R&D personnel give full play to their imagination and make full use of the flexibility and adaptability of the prototype to design more and better colorful products. Proofing machines often have drawing function, and the price of professional pen plotters with large working range is relatively high. The price difference between the two is not big, but the function is incomparable to pen plotter.

Packaging printing is an industry that serves the packaging of industrial and agricultural products. With the further deepening of China's market economy, the improvement of people's material and cultural level and the development of foreign trade, the packaging and printing industry has also developed and expanded. Since the reform and opening up, China's packaging and printing industry has made great progress, but there is still a big gap compared with foreign developed countries. The commodity economy in the southeast coast of China is relatively developed, and the packaging and printing industry is also developing simultaneously. Coupled with forward-looking thinking, the application of proofing machines is more popular, and some manufacturers even have more than two proofing machines, or run 24 hours a day. Moreover, more and more manufacturers are interested in buying, so as to enhance the competitiveness of their products.

However, it should be noted that because there are only a handful of domestic professional prototype manufacturers, most of them still adopt some basic types of foreign machines to improve, and they start late, the technology is backward, the accuracy and stability of the machines are still difficult to guarantee, and there are shortcomings in technical support, so they can only have a certain competitive advantage in price, so as to seize some low-end markets. However, with the opening and development of China market, we must strengthen the development of independent brands and technologies and upgrade our products, otherwise it will be difficult to form a big market. Therefore, at present, the carton factories with real demand and high requirements are mainly imported machines. Although the price is high to a certain extent, the stability, high speed and high precision of the machine performance make it the first choice for those middle and high-end manufacturers. With the reform of China's foreign exchange market, the further reduction of machinery import tariffs and the strengthening of after-sales service technical support, it is believed that the markets in Guangdong and other coastal areas will continue to expand in the next few years, and a certain market will also be formed in China. [File system: page]

In China's packaging and printing industry, the production capacity of middle and low-grade printing products is surplus, and the production capacity of high-grade exquisite or middle and high-grade printing is insufficient. With the rapid development of high technology in the world, especially after China's entry into WTO, China's packaging and printing industry will be greatly impacted by its foreign counterparts. In order to make China's packaging and printing industry integrate into the world economic tide and participate in global economic competition, we must arm the packaging and printing industry with high and new technologies, increase the pace of technological innovation and adjustment of technical equipment, and accelerate the reform of economic system. Strive to popularize and apply color desktop system in China's packaging and printing industry in a few years, and some large and medium-sized enterprises adopt CTP direct plate making and digital proofing technology to realize prepress digitalization and networking; CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) system is adopted for the design of cartons and the trial production of cartons samples. Printing technology is developing towards multi-color and high efficiency. Offset printing accounts for 60%, flexographic printing accounts for more than 35%, and other printing accounts for 5%. Post-press finishing should improve the degree of automation, shorten the auxiliary time, and develop large-format, high-speed, high-precision, multifunctional and fully automatic post-press processing and its peripheral equipment. Gradually realize the automation and continuity of stamping, polishing, embossing, die-cutting indentation, box pasting and other processing technologies to meet the requirements of multi-variety, high quality and short cycle in the market.

(2) What's the difference between a proofing machine and a printing machine?

1. The structure of the proofing machine is different from that of the printing machine.

The proofing machine adopts circular flat printing method, and the printing machine adopts circular flat printing method; The water supply and ink supply mechanism on the proofing machine is far from perfect on the printing machine, so there will be a certain gap between the proofing sample and the printed matter in ink balance, dot reduction, image level and so on.

2. The printing process of the proofing machine is different from that of the printing machine.

Multicolor printed matter is printed continuously on the printing machine and intermittently on the proofing machine, one by one, one color by one. Continuous printing determines that the printing press adopts wet pressing and wet pressing printing, while the intermittent time of the proofing machine is long. When printing a color, the previous color is dry, so it is usually done by wet pressing. These two methods determine that proofs and printed matter will have different printing effects. For example, when printing gold ink on the spot, printing gold once when proofing may achieve the ideal effect. But on the printing machine, two or three units arranged behind the field printing unit can't print gold, and gold can't be printed until the field color block is dry. In addition, gold and silver cardboard printed matter cannot be polished online, otherwise the positive imprint will be removed by polishing oil.

There is no paper feeding and receiving process on the proofing machine, but there is one on the printing machine. This leads to the failure of gold and silver paper jam or the imprint on the surface of printed matter being scratched by the paper feeding mechanism, or the paper is too deformed to feed paper smoothly. When receiving paper, if the ink layer is not dry, it will also cause the printed matter to stick dirty, or scratch the printed matter due to the relative movement between the papers, and the imprint on the back of the printed matter will be scratched by the suction wheel. Therefore, powder spraying is often used to prevent sticking when collecting paper. After powder spraying, the gloss of printed matter may decrease and the surface may be rough; Or when overprinting on the computer for the second time, the color of the ink behind it is not true; It may also be because too much powder spraying will bring hidden dangers to later processes (such as laminating and bronzing). Of course, sometimes additives in ink will also affect the printing effect. In addition, some papers are too thin, which will be rolled into a ball after printing on the printing machine, and it is impossible to receive the paper.

Generally, the proofing machine prints at low speed, while the printing machine runs at high speed. In order to achieve a certain effect, some samples need a thick ink layer, which is impossible in normal high-speed printing, and ultra-thin ink layer is also difficult to control in high-speed printing.

The printing pressure of the printing press is greater than that of the proofing machine, and the same paper can be used normally during proofing, so the paper peeling may occur on the printing press.

3. Other aspects

Whether proofing on a proofing machine or printing on a printing machine, paper will expand and shrink to a certain extent, but its expansion and shrinkage are different. Generally, the proofing expansion rate is small on the proofing machine, and the printing expansion rate is large on the printing machine. Therefore, if multi-color overprinter needs to be printed on the computer for many times, in the second overprint, there may be obvious overprint prohibition due to paper deformation, and the paper deformation is irregular.

In multi-color printing, it often happens that the ink prepared according to the ratio of proofing ink has great color difference when printing. This may be because there are other colors of ink on the ink roller when proofing. Although these residual inks are few, they account for a large proportion of the few inks used in proofing. Therefore, the ink roller should be cleaned when proofing. Of course, sometimes different paper colors can also cause chromatic aberration.

The printing film for proofing is generally a single imposition, and the printing film for printing production is generally a multi-imposition. When multi-imposition film is copied from single imposition film, misregister or even dot loss may occur, resulting in deviation between printed matter and sample.

When printing on a printing machine, we should also consider pH value, additives (such as red, white and drying oil, ink blending oil, etc. ) and the use of drying devices.

Therefore, possible problems in printing production should be taken into account when proofing, and problems in proofing should also be taken into account when printing, and appropriate adjustments should be made to make the products printed on the printing machine close to the proofs printed on the proofing machine.