Design of a Sensor System for On-Line Monitoring of Contact Pressure in Chalcographic Printing

Abstract

Chalcographic printer is the name given to a specific type of press which is used to transfer the printing of a metal-based engraved plate onto paper. The printing system consists of two rollers for pressing and carrying a metal plate onto which an engraved inked plate is placed. When the driving mechanism is operated, the pressure exerted by the rollers, also called contact pressure, allows the engraved image to be transferred into paper, thereby obtaining the final image. With the aim of ensuring the quality of the result, in terms of good and even transfer of ink, the contact pressure must be uniform. Nowadays, the strategies utilized to measure the pressure are implemented off-line, i.e., when the press machines are shut down for maintenance, which poses limitations. This paper proposes a novel sensor system aimed at monitoring the pressure exerted by the rollers on the engraved plate while chalcographic printer is operating, i.e., on-line. The purpose is two-fold: firstly, real-time monitoring reduces the number of breakdown repairs required, reduces machine downtime and reduces the number of low-quality engravings, which increases productivity and revenues; and secondly, the on-line monitoring and register of the process parameters allows the printing process to be reproducible even with changes in the environmental conditions or other factors such as the wear of the parts that constitute the mechanical system and a change in the dimensions of the printing materials. The proposed system consists of a strain gauge-based load cell and conditioning electronics to sense and treat the signals.

Desenvolvimento De Metodologia De Apoio À Decisão Para Manutenção Inteligente Combinando Abordagens Multicritério E Machine Learning: Estudo De Caso Em Empresa De Manufatura

“…Outra técnica de impressão é a calcografia, sendo definida como a arte da impressão em relevo, utilizando-se de rolos e placas de metal entre outros componentes. Por derradeiro, a última impressora estudada emprega a impressão serigráfica, onde a tinta passa pelas áreas permeáveis e imprime sobre o substrato desejado, podendo ser dos mais diversos tipos de superfície, tais como papel, madeira, metal, tecido, alvenaria, plástico, vidro (Jiménez et al, 2017;Aminger e De Menezes, 2021).…”

“…Já as impressoras calcográficas tem como base dois rolos para prensar e transportar uma placa metálica sobre a qual é colocada uma placa gravada com tinta. Quando o mecanismo de acionamento é ativado, a pressão exercida pelos rolos, também chamada de pressão de contato, permite que a imagem gravada seja transferida para o papel, obtendo-se assim a imagem final (Jiménez et al, 2017).…”