Patent ID: 7335280

Claim:
A method in the measurement of the flatness of a flow surface of a headbox of a paper machine, in which, according to the method, the flatness of the flow surface is determined by placing a measuring tool on the flat surface formed by the flow surface at several different points in the transverse direction and measuring the position of the measuring tool at each point, the method comprising the steps of: arranging a measuring sensor at at least two points in the longitudinal direction of the measuring tool, in order to determine the distance between the measuring tool and the flat surface at the points at which the measuring tool is placed, said measuring tool being set for a period of time at one of said points in the transverse direction of the headbox and after said period of time the measuring tool being moved in the transverse direction of the headbox to another of said points in the transverse direction of the headbox; reading relative dimensions provided by the measuring sensors at each said point in the transverse direction of the headbox, and combining the position of the measuring tool and the dimensions from the measuring sensors, in order to determine the absolute values of the measured points; arranging an angle sensor in connection with the measuring tool; and determining the longitudinal alignment of the measuring tool by means of said angle sensor.