Patent ID: 7798382
Filing Date: 2010-09-21
Classification: B65H

Abstract:
1. A method for regulating a web tension of a continuous material moving with a transport device, comprising the steps of: determining a master axis speed based on a speed of a drive element in a point of feed of the continuous material and on a speed of a drive element in a point of carry-away of the continuous material; determining a material physical characteristic in a point between the material feed point and the material carry-away point by a primary detector; determining the web tension of the continuous material by a web tension controller based on the determined master axis speed and the material physical characteristic; and using the web tension determined by the web tension controller to regulate the web tension by the web tension controller so as to hold the web tension within an increased operating range of the transport device and to hold properties of the web material within a range which is appropriate for a processing quality, wherein the web tension has an amplification as a function of a deviation from a predetermined setpoint value for the web tension, wherein a change of amplification has a flat characteristic when the deviation from the setpoint value is less than a preselected maximum value, and wherein the change of amplification has a steep characteristic when the deviation from the setpoint value reaches or exceeds the preselected maximum value, so that when said amplification has said flat or steep characteristic, the web tension controller is adapted automatically to control the web tension to the setpoint value according to said amplification.