Method and device for on-line detection and fault diagnosis of longitudinal registration of printing machine

Abstract

The invention relates to the field of printing machine overprinting error on-line detection and fault diagnosis, in particular to a printing machine vertical alignment online detection and fault diagnosis method and device which can measure printing roller motion errors. The method comprises the steps of S1, using a color code sensor to detect various color code signals distributed in the circumferential direction of the printing roller, comparing the signals with a location encoder, conducting motion error compensation to obtain an initial overprinting detection error Lij0(t); S2, using a CCD image sensor to detect a cross curve overprinting error Lij1(t), conducting compensation to obtain a precise overprinting error; S3, calculating the difference between the initial error value and the precise error value by using the equation delta Lij (t) = Lij0 (t) -Lij1 (t); S4, using the difference delta Lij (t), speed, vibration and other information to establish a mathematical model, training with a neural network system, conducting online precision compensation to the initial error value to obtain an overprinting error Lij(t) nearing the true value; S5, at the same time, it is possible to use the multi-information fusion theory to diagnose out the reasons of the overprinting, electrical and mechanical faults. Compared with the prior art, the printing machine vertical alignment online detection and fault diagnosis method and device has a high online detection precision which can reach 10 micrometers, the detection speed is fast, and the device has the function of diagnosing faults and other advantages.

Description

technical field [0001] The invention relates to the field of printing machine overprint error detection and fault diagnosis, in particular to a printing machine longitudinal registration online detection and fault diagnosis method and device for measuring printing cylinder movement errors. Background technique [0002] With the rapid development of the printing industry, the mechanical performance of printing machines has been greatly improved, and it is gradually developing towards shaftless, high-speed, and intelligent. Shaftless means that the power of each unit in the printing machine, or even each roller or stick, is independent of each other, using separate servo motors to drive according to the program instructions issued by the motion controller, so as to ensure the synchronization between the units The transmission mode of operation. Shaftless transmission technology is widely used in modern printing presses and is one of the mainstream printing press technologies....

AI Technical Summary

Problems solved by technology

This overprint error detection method uses hardware to subdivide the collected signal to improve the resolution to improve the accuracy of overprint error detection. It does not take into account the influence of the mechanical transmission system and system dynamic factors on the detection equipment. The measured value is different from the actual value. is biased

In addition, "Patent No. CN105291561 A Overprint Accuracy Detection System and Overprint Accuracy Detection Method" proposes an overprint accuracy detection system. This system uses two specially arranged induction color mark probes to detect color mark signals, and calculates the overprint accuracy according to the sensing time interval. Deviation has a certain practical value, but the overprint error detected by it is affected by the installation position error of the two probes, and the accuracy is limited. At the same time, the influence of the mechanical transmission system and system dynamic factors on the detection equipment is not considered.

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