IT1108201B - Feeder and positioner of continuous tissue web for shearing - has control circuits regulating stepping motor by pulsed signals - Google Patents

Abstract

A continuous web of tissue is fed forward to be cut into sections and is stopped at predetermined positions. The sections are to be cut in a predetermined zone, and the equipment includes means by which the tissue is cut periodically in conformity with work cycles corresponding to the formation by the feeder of the section to be cut. Means are also provided for feeding the tissue to the cutting arrangement and there are means of detecting a reference marking on the tissue which indicates the cutting zone. The control system includes means of checking the predetermined cutting zone relatively to the zone which would be cut through by the cutters, and of determining any difference between the two zones. Further means are provided to adjust and correct the possible difference mentioned relatively to the zone of action of the cutters. These means are arranged to receive direct or indirect signals from the first means of control, as a function of the possible difference mentioned, and to activate the feeder and/or the cutters so that the possible difference mentioned relatively to the zone of action of the cutters is eliminated. The device is not only able to detect the position of faults in the centralising of the zones for cutting, but can determine them and correct them for each separate section. The device is also able to detect differences in the pitch between one check motif and the next, and detectors can be positioned wherever they are required or according to the available space.