method and device for measuring the diameter of a bahnwickels

摘要

The method for measuring the diameter of a reel or roll of wound web material (N) involves the following steps: rotating said reel (L); detecting at least twice the moment when a given point (Lf) on the web material (N) passes a predetermined position; determining the time that elapses between said two passes or the amount of rotation (alpha) of the supporting roller (5); and calculating the diameter (D) of the reel (L) from said time (T) and the peripheral speed (V) of the reel (L) of from said amount of rotation (alpha) and the radius (R) of the supporting roller (5).