| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately detect the presence or absence, and dimensions of hole- like defects that are generated in a metal strip. SOLUTION: Light that is radiated from a light source 24 toward one surface 23 of a metal strip 22 that runs in the longitudinal direction is regularly and irregularly reflected on the surface of a reflection roll 28 that is provided in contact with the other surface 27 of the metal strip 22 when the metal strip 22 has a hole-like defect on one surface 23 or the metal strip 22 when the metal strip 22 does not have any hole-like defects. Regular reflection light 29 that is regularly reflected on one surface 23 of the metal strip 22 or the surface of the reflection roll 28 is detected by first a photosensor 30, and irregular reflection light 31 that is reflected irregularly is detected by a second photosensor 32. The presence or absence, and dimensions of the hole-like defect are inspected based on the light intensity of regular reflection light 29 and the irregular reflection light 31 that are displayed on a display means 33 in response to the detection output of the first and second photosensors 30 and 32.</p> |
