Graphics machine and process for monitoring printing material using such a roll of sheet printing material wound on a core, and roll usable for such a machine and such a process

摘要

In a graphics machine comprising means for receiving a roll (14) of sheet printing material wound on a tubular core (16), there is provided a reading device (40), for example optical, capable, during rotation of the roll, of reading coded information, for example in the form of a bar-code (50), which information is carried by the tubular core and relates to at least one characteristic of the printing material, such as the nature of the material, the initial length of the roll, the width of the sheet, the identification number of the roll. Detection of the information furthermore makes it possible to provide an indication regarding the correct positioning of the roll, the speed of rotation thereof, and to calculate continuously the length of sheet remaining on the roll. The information read is transmitted to a unit for controlling the machine which controls in particular a writing device and entraining means for effecting a relative displacement between the printing material and the writing device. <IMAGE>