A fully enclosed double negative pressure circulation ink supply system for a digital inkjet printing machine

Abstract

The invention discloses a fully-enclosed double negative pressure circulating ink supply system for a digital inkjet printer. The fully-enclosed double negative pressure circulating ink supply system comprises an ink barrel, a negative pressure ink supply device, a negative pressure ink return device and a controller, wherein the negative pressure ink supply device and the negative pressure ink return device are used for conveying ink to a printing head; the controller is used for intensively controlling the negative pressure ink supply device and the negative pressure ink return device to supply the ink in a cyclic way; the controller is connected with a memorizer; the negative pressure ink supply device comprises an ink supply box, an ink supply air pressure adjusting unit and an ink supply level adjusting unit; the negative pressure ink return device comprises an ink return box, an ink return air pressure adjusting unit and an ink return level adjusting unit; the printing head is a double negative pressure printing head; the vacuum degree of an ink outlet end of the double negative pressure printing head is higher than that of an ink inlet end; the ink barrel communicates with the ink supply box and an ink return box separately; and the ink supply box and the ink return box are gas-liquid buffer type enclosed ink boxes. The ink pressure in the ink boxes is controlled by adopting an air pressure level adjusting mode through differential flow between double ink pumps; circulating ink quantity of the printing head is effectively and stably controlled through the vacuum degree difference between two ends of the printing head; dynamic printing is achieved; and the adaptability is high.

Description

technical field [0001] The invention belongs to the technical field of ink supply for printing machines, and in particular relates to a fully enclosed double negative pressure circulation ink supply system for a digital inkjet printing machine. Background technique [0002] In recent years, with the rapid development of digital inkjet printing technology, print head technology has also been greatly improved, and a large number of industrial-grade digital inkjet print heads have emerged. Traditional print heads mostly use open positive pressure ink supply. The siphon method or differential pressure method is mostly used to realize the ink pressure, and the usage rate of the negative pressure ink supply printhead is relatively small, and most of the negative pressure ink supply printheads that are used also use the negative pressure air bag method of the vacuum proportional valve. To achieve ink pressure. These ink supply methods can be used on small inkjet printers, but they...

AI Technical Summary

Problems solved by technology

These ink supply methods can be used on small inkjet printers, but they cannot be used on large industrial-grade high-speed digital inkjet printers. Many problems such as insufficient ink supply, unstable ink pressure, and ink bleeding of the print head will occur.

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