Patent ID: 7793589
Filing Date: 2010-09-14
Classification: B41F

Abstract:
1. Cloth feed control unit of a cleaning device for printing machine cylinders, comprising: a cleaning device designed for rotational positioning of two cloth rollers, one cloth roller being a clean cloth roller and the other cloth roller being a dirty cloth roller, the dirty cloth roller being driven step-by-step by an automatic drive unit in order to transfer a cleaning cloth in a step-by-step manner by a predetermined cloth feed length from the clean cloth roller to the dirty cloth roller, the predetermined cloth feed length corresponding to a desired value, the two cloth rollers having variable roller diameters, a non-contact position sensor, which is designed for generating signals linearly in proportion to radial variations in a distance from the outer circumference of one of the two cloth rollers to the position sensor, the position sensor being positioned radially with respect to a rotational axis at a predetermined radial distance from a rotational axis of at least one of the cloth rollers, so that the signals correspond to a respective radius of at least one of the cloth rollers; an encoder having a rotation element that is in joint rotation and connected to at least one of the cloth rollers, and the encoder further having an encoder sensor for detecting the rotational element; a control element, having the encoder sensor connected thereto, the control element calculates a respective size of the circumference of at least one of the respective cloth rollers from the signals of the position sensor, the respective size corresponds to the radius of at least one of the respective cloth rollers; the control element further being able to store a cloth feed length-desired value; and a predefined number of rotational angle-increments for the 360[deg.] circumference of at least one of the cloth roller; the control element being able to calculate how many increments at least one of the cloth roller has to be rotated in order for the drive unit to transport the cleaning cloth by one cloth feed length, which corresponds to the cloth feed length desired value, given the calculated respective size of the circumference of the respective cloth roller, and the control element further being able to generate an actuating signal-desired value for the drive unit which corresponds to the calculated increments.