New structure and advanced technology of the hotte

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New structure and advanced technology of satellite flexo printing machine

satellite flexo printing machine, also known as central impression or central impression cylinder flexo printing machine, is the most important type of flexo printing machine. Some data show that in European and American countries, the proportion of satellite flexo printing machines in all flexo printing machines is as high as 70 ~ 80%. In China, flexo printing technology is being more and more widely used, and the satellite flexo printing machine will become a major model in the application field of flexo printing machine in China. In addition, some printing machine manufacturers in China have begun to develop such equipment. Therefore. It is of great significance to understand the latest technology development status for the introduction of equipment or research and development

satellite flexo printing machine has many advantages: its control system is relatively simple and its investment is low; High overprint precision and high production efficiency; The production line is stable and reliable, and has a wide range of applications. The satellite flexo printing machine is mainly used in the fields of flexible packaging, carton, label and corrugated box pre printing. Generally speaking, the components of the satellite flexo press include: unwinding and input part, printing part, drying part (color drying and final drying), cooling part, output and winding part or wire processing part, main drive and control part, etc

the technical level of the satellite flexographic press can be accurately expressed by the following performance systems: the maximum number of printing colors and printing arrangement, printing materials and printing width, the range of printing text repetition length, drying method, printing speed, suitable printing materials and ink types, but it is its control and automation system that centrally reflects the technical level of the flexographic press. Although flexo printing machines use a variety of control and automation systems. But it can be roughly divided into semi-automatic type and full-automatic type

the following briefly introduces the new structure and advanced technology of the satellite flexo press:

sleeve type plate cylinder and embossing roller

there are two types of plate cylinder and embossing roller: integral type and sleeve type

the integral type has simple structure, good rigidity and wide application range, but the replacement is complex. The sleeve type is easy to replace, but the structure is complex. Each component is equipped with a pneumatic quick clamping and loosening device. Due to its low cost, easy loading and unloading, high flexibility, long service life, convenient storage, high system accuracy and rapid version change function, the sleeve type plate cylinder has been widely used in flexo printing and gravure printing, and will gradually replace the traditional printing plate

the sleeve type plate cylinder (or sleeve type corrugated roller) is composed of a mandrel, an air support roller (empty roller) and a sleeve. When replacing the plate cylinder (or corrugation roller), as long as the air pressure switch on the printing unit is turned on, the compressed air is input to the inflation roller, and then discharged evenly from the small hole of the inflation roller to form an air cushion, so that the inner diameter of the sleeve is expanded and expanded. The original plate cylinder (or corrugation roller) sleeve will pop up automatically. Replace the new plate cylinder (or corrugation roller) sleeve, and the new sleeve can slide to the required position on the inflation roller easily and conveniently. Turn off the air pressure switch, and the plate cylinder and the embossing roller will be fixed. When the compressed air is cut off, the sleeve will shrink immediately and be fastened with the air expansion roll. The inner diameter of the sleeve is generally smaller than the outer diameter of the air support roll to ensure its engagement. Two or more sleeves can be installed on the same inflatable roll. If the sleeve needs to be replaced or removed, just inflate the inflation roll again. The circumference and diameter of the sleeve of the plate cylinder (or corrugation roller) of the new satellite flexo press can be changed, while the size of the mandrel remains unchanged

the greatest advantage of the sleeve type plate cylinder is that it can be reused, and the photosensitive resin plate can be pasted on the sleeve at any time. In addition, the sleeve can also be used for laser engraving and plate making. The seamless flexo is used to print continuous patterns or patterns with the same background color. If the allowable printing perimeter change range of the sleeve system is 150mm, it means that the inner diameter of the sleeve with a printing perimeter of 350 ~ 500mm is the same, and only one inflatable roll is required. By changing the wall thickness of the sleeve, the circumference of the sleeve can be changed

gearless direct drive technology

the plate cylinder and the embossing roller of the old flexo press rotate synchronously by driving the plate cylinder gear through the embossing cylinder gear, and the plate cylinder gear drives the embossing roller gear. The repetition length of the printed matter depends on the gear of the plate cylinder and the plate cylinder, and the gear is limited by the pitch and modulus. Therefore, the repetition perimeter of the printed matter is the same as the pitch of the gear. The rotation of the new flexo printing machine's embossing roller is directly driven by the plate cylinder, which solves the problem that the repetition length of the flexo printing machine's printing products is limited by the gear pitch

each printing unit of the satellite gearless flexographic press is driven by 7 motors, of which 4 motors drive the plate cylinder and the embossing roller to move back and forth, 1 motor controls the vertical registration and rotation of the plate cylinder, 1 motor controls the horizontal registration and horizontal movement of the plate cylinder, and 1 motor drives the rotation of the embossing roller. The circumference of the plate cylinder input into the plate cylinder after plate loading is welcome to visit our factory. Through PLC control, the plate cylinder and the embossing roller reach the pre printing and pre registration position, which greatly shortens the printing pressure and printing registration time, and also saves raw materials

at the same time, due to the gearless transmission, it is not necessary to replace the gear when replacing printing products with different perimeter. It takes only 1 minute to replace the flexographic cylinder and corrugation roller on a unit of the gearless satellite flexographic press, which greatly shortens the time spent replacing the cylinder and corrugation roller when replacing products

the automatic registration system of the satellite flexographic printing machine launched by Germany eromac company uses one registration probe to control the registration of all printing units of the flexographic printing machine, unlike the gravure printing machine, which requires six registration probes and auxiliary motors for seven color printing. When printing products are not overprinted on time, the registration probe directly drives the motor to adjust the driving puller of the horizontal testing machine and the driving frame connector of the reaction frame to connect the longitudinal and transverse overprint positions of the whole printing plate cylinder through the PLC. Unlike the longitudinal registration of gravure, the printing plate cylinder is adjusted through the auxiliary motor. The eromac automatic registration system is used to adjust the printing plate cylinder, which takes less time and consumes less printing materials. The system can automatically register according to the registration cross line, and can also register according to the manual setting, so as to solve the error between the printing pattern and the registration cross line during plate making and plate pasting

closed double scraper cavity ink conveying system

although the flexo printing machine adopts the two roller type, the forward scraper type and reverse scraper type structures to realize the quantitative ink supply, these types of ink are all open type, and the ink is stored in the ink tank. Part of the ink on the ink roller is used for printing, and the rest is returned to the ink tank. This open structure makes the ink directly exposed to the atmosphere in a large area. If solvent type ink is used, Solvent volatilization into the air will cause changes in ink characteristics and environmental pollution; If water-based ink is used, it is easy to produce bubbles and affect the printing quality

satellite wide flexo printing machines mostly adopt a fully enclosed double scraper ink conveying system. The ink conveying system consists of a scraper base, two scrapers, a side sealing plate made of wear-resistant soft materials and a corrugated roller to form a closed ink chamber. The ink is sprayed onto the surface of the corrugated roller through the ink port and stored in the ink chamber. The ink is scraped by the reverse scraper and sealed by the forward scraper. According to the principle of hydrodynamics, the ink or cleaning agent is in a flowing state in the ink bucket. Therefore, even if a small amount of ink is injected, it can be recycled. A small amount of cleaning agent can be used for rapid cleaning. Because of its good sealing property, it is of great benefit to health and environmental protection. The closed double scraper cavity ink conveying system is composed of ceramic roller, two scrapers, sealing strip, ink storage container, ink pump, ink conveying hose and other components. In the fully enclosed system, the scraper, seal strip, gasket and pressing plate are all installed on a cavity support. They are pushed to the ceramic roller mechanically (or pneumatically or hydraulically), and a certain pressure is applied. Then the ink delivery pipe and the return pipe are connected to the ink pump and the ink storage container respectively. The system has the following characteristics: the quantitative ink supply system adopts the reverse scraper structure, which is suitable for high-speed operation, avoids the problems of solvent volatilization and environmental pollution in solvent based ink, and solves the problem of foam accompanying the use of water-based ink. The system can also be quickly connected with the automatic cleaning system to facilitate rapid cleaning and reduce ink change time and downtime

non stop quick roll changer

the pressure roller device and the belt breaking device work in a pneumatic manner, and the pneumatic electric tension measuring and adjusting device is used to ensure constant tension. The automatic paper receiving mechanism can work normally even at the maximum paper roll diameter, thus ensuring the tension control at the highest printing speed. In order to ensure that the edge position of the substrate entering the printing part is always correct. For opaque materials such as paper, a deviation correction device composed of a photoelectric scanning head or an ultrasonic sensor is also used. When printing paper or paper jam, sometimes it is necessary to adjust the temperature and humidity. When printing plastic film or aluminum foil. A corona treatment device should be prepared to improve the inking ability of the film surface

temperature controlled imprinting cylinder and high-power drying/cooling system

the imprinting cylinder of satellite flexographic printing machine adopts double-layer wall structure. It is beneficial to the temperature control of the embossing cylinder. The surface of the impression cylinder is provided with a nickel plating protective layer. The thickness of nickel layer is about 0.3mm. The imprint cylinder is installed on the roller bearing to control the eccentricity error of the imprint cylinder within 0.008 ~ 0.012mm. The imprint cylinder shall be subject to dynamic balance and static balance. The imprinting cylinder is equipped with a water circulation system to keep the external surface temperature of the imprinting cylinder constant and prevent the imprinting cylinder from thermal expansion. Some flexo printing machines also have the function of over temperature protection. When the temperature exceeds a certain maximum value, the power supply of the whole printing machine will be cut off automatically

double loop circulating air is used in the color drying device and Bridge drying device between printing color decks to reduce the demand for fresh air and reduce the consumption of heating energy

modular intelligent control and management system

the control and management system of the satellite flexo printing machine has three forms: the rapid control system based on manual adjustment, the electronic information system based on automatic adjustment and the digital control system based on full-automatic adjustment. The digital control system drives the printing unit by seven stepping motors, manages and monitors the printing area by using PC/PLC technology, realizes the automatic registration in the axial and circumferential directions and the low-speed rotation of the wrinkle roller during shutdown, and provides fault diagnosis for the whole printing machine through the modem

modern satellite flexo printing machine mainly has the following control and management functions:

■ modular automatic operation system, which can not only pre select menu, centrally operate unwinding/rewinding unit, printing unit and drying unit, but also select camera observation module to view the whole printing process on the display screen

■ the intelligent transmission system and positioning system ensure the accurate movement and horizontal registration of the printing plate cylinder and corrugation roller of various color groups

■ electronic synchronous adjustment and computer-controlled fast forward system ensure highly accurate setting of parameters such as printing pressure, printing length, printing plate and substrate material thickness through stepping motor speed measurement. Ensure that no waste products will be generated during the registration setting of the equipment in the shutdown state, and realize the coordination between the printing unit and the corrugated roller

■ manipulator roll change system for automatic replacement of plate cylinder and embossing roll

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