Patent ID: 7413139
Filing Date: 2008-08-19
Classification: B65H

Abstract:
1. A control device for controlling tension of weblike material coming out of a first station and fed to a second station of a system comprising: at least one member for regulating speed of advance of said weblike material along a feed path between said first station and said second station; a central control unit moves the weblike material along the path, said weblike material is run over a guiding roller with a mobile axis; and a position transducer for detecting position of the guiding roller and for generating a position signal for controlling the speed of said weblike material; wherein said guiding roller is supported in a controlled position and associated therewith at least one sensor for detecting a load applied by the weblike material on the guiding roller; an actuator for controlling displacement of said guiding roller according to a feedback signal generated by said sensor, the actuator being controlled so as to make up for variations of said load moving the axis of the guiding roller; and said member for regulating the speed of advance of said weblike material is controlled by said central control unit according to the position signal to maintain the axis of the guiding roller in a position that is on average constant; wherein said control unit determines, based on the position signal coming from said transducer, trend in time of the position of the axis of said guiding roller; and said control unit causes, by means of said member for regulating the speed of advance of the weblike material, a variation of the speed of the weblike material when a mean value of said position exceeds a threshold value from a pre-set mean position (α m ).