| 摘要 |
<p>PURPOSE:To provide a metal web's position determining method by which position control the width direction and temporary stop can be carried out surely even if the running metal web is extremely thin and easy to sag. CONSTITUTION:To the surface of a running metal web 1 which contains an exposed metal part 2 and a transparent film surface 3 touching the exposed metal part 2 through a boundary line 11 extended in the longitudinal direction and/or a boundary line 17 extended in the transverse direction, heat-beam 13 is radiated diagonally along the boundary line's 11 direction to contain the boundary line 11 and/or crossing the boundary line 17 from a heat source 12 having different surface temperature from the temperature of the metal web 1. The heat-beam 13 reflected by a spot part 16 containing the boundary line within the radiation surface is detected by a sensor 15 which corresponds to the specific absorption wavelength of the transparent film and based on the output of the sensor, the position in the transverse direction of the metal web 1 is controlled and/or the metal web 1 is stopped running.</p> |
