Bisectional four-color offset press

Abstract

The present invention relates to a dimidiate four colour offset press of printing industry, comprising a paper transport mechanism, four printing units, a paper transfer roller, a paper accept mechanism, a machine frame, wherein the four printing units are respectively arranged on the machine frame; the printing units are composed of a water ink system, a plate cylinder, a rubber blanket cylinder, an impression cylinder, a follow-up mechanism, a clutch press mechanism; the paper transport mechanism uses non-round gear sets to adjust feeding speed of the paper; the water ink system is a mechanism used for inner cycles with hollow changing ink stick structure, temperature control and feedback device; the plate cylinder is a forme mechanism with a diagonal regulation mechanism, a circumference direction regulation mechanism, an axial direction regulation mechanism, a quick letterpress makeready device; because the paper transport mechanism regulates speed by engaging the two sets of non-round gear, the paper transport mechanism is provided with a position detecting feedback device, a changing ink stick is designed to structural form of regulating temperature control, a forme regulating device is provided on the plate cylinder, thereby the printing quality is good and the automation control degree is high.

Description

technical field [0001] The invention relates to an offset printing machine in the printing industry, in particular to a split four-color offset printing machine. Background technique [0002] After retrieving relevant patent documents, no folio four-color offset printing machine with the same structure as the present invention has been found. Due to various reasons, it is difficult to improve the printing quality of offset printing machines produced in China. The first is the problem of speed. When the sheet-fed offset printing machine completes the printing function, it needs to separate the paper one by one from the paper pile, and transport it to the regular place for positioning. When the relative speed is zero, it is accurately delivered to the paper transfer or impression cylinder. Due to the large impact force of the paper during the transportation process of the existing paper feeding method, the end of the printing paper is prone to bending after the impact. There...

AI Technical Summary

Problems solved by technology

Due to various reasons, it is difficult to improve the printing quality of the existing domestically produced offset printing machines

The first is the problem of speed. When the sheet-fed offset printing machine completes the printing function, it needs to separate the paper one by one from the paper pile, and transport it to the regular place for positioning. When the relative speed is zero, it is accurately delivered to the paper transfer or impression cylinder. Due to the large impact force of the paper during the transportation process of the existing paper feeding method, the end of the printing paper is prone to bending after the impact. Therefore, the quality of printing is difficult to meet higher requirements; secondly, the existing ink system generally does not have a temperature control system during printing. The sticks and water sticks rub against each other, the temperature of the machine rises, and the ink is more likely to be thinned, so that the ink of the printing plate changes, making it difficult to stabilize the quality of the printed product; third, when printing paper with different thicknesses, it is generally used Manually adjust the center distance between the rubber cylinder and the printing plate cylinder, but due to the time-consuming manual adjustment, high technical requirements, low work efficiency, and unstable quality; fourth, it is often necessary to temporarily stop printing during the printing process and adjust it so that the rubber cylinder separate from the impression cylinder

The clutch pressure mechanism of the domestic offset printing machine is generally controlled by the cam drive method. Since the contact speed between the cam and the contacting roller is fast during high-speed offset printing, the cam is easy to wear, and the vibration is large, which is easy to damage the parts.

Fifth, in order to adjust the position of the printing plate on the existing printing plate cylinder, it is generally adjusted manually. Since the quality of manual adjustment is difficult to control, it is even more difficult to meet the requirements when printing high-quality goods

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