| 摘要 |
<p>PURPOSE:To obtain an apparatus of higher standard of accuracy, to furnish the apparatus with a plurality of low-path filter for cutting high-frequency of a distance signal, arc-length calculating set for the arc-length of the distance signal and the least-value detecting set for the least value of arc-length signal. CONSTITUTION:A flatness detector is provided with a plurality of low-path filters 5 for cutting high-frequency wave of distance signal measured by a plurality of distance measuring sets, a plurality of arc-length calculating sets 3 for calculating arc-length of the signal from this filters 5, the least value detecting set 6 detecting the least value of output from the arc-length calculating sets 3, and relative elongation ratio calculating set calculating the relative elongation ratio from arc-length signal of each channel and the least value signal of the arc-length signal. In this case, in order to remove vibration and wavy motion of a ribbon material, as low-path filter and least value detecting set are added, detection can be limited only to detective shapes and accordingly, accuracy can be improved.</p> |
